Volume 16 Number 1 t997

ALISO

A journal of taxonomic and evolutionary botany

Rancho Santa Ana Botanic Garden, Claremont, California

ISSN: oo65'6275 Aliso. 16(l), pp. 1-71 O 1997. by The Rancho SantaAna Botanic Garden, Claremonr,CA 917ll-3 157

THE EUPHORBIACEAE OF SONORA. MEXICO

VrcroR W. Srr,rNnrRNN

Rancho Santa Ana Botanic Garden I500 North College Avenue Claremont, Calfornia 9 I 7I 1 and Universitl, of Ariz.ona Herbarium l l3 Shantz Building Tucson, Ariutna 8572 1

AND

RrcsRRnS. Felcrn Dryland.s In.stitute 2509 North Camnbell Avenue #405 Tucson,Arizonct 857I9

AtsSTRAC'I

This publication is iln accountofthe Euphorbiaccacin the stateo1'Sonora. M6xico. Ninctccn gcncrt. 143 species,and three additional varictics arc recorclccllirr the state;three spccieserpcctctl within tlrc state are irlstt trcatcd. ()ne specics of Acultltho antl three species and one subsl.rccics

RBSL MF.N

Esta publicaci(rncs un estudio dc h tnnrilia liuphorbiaccac cn cl cstado clc Sonora, M6xico. Sc rcportan l9 gdneros,l,{3 cspcciesv -l varicdades;se incluycn aderrristres cspcciesque probablemente estdn prescntcscn Sonora. Se dcscribc una cspccic tlc Atulvplru y trcs especiesy una subespccicdc I')upfutrbiu. Se proporcionan claves para la identihcaci6n de 96neros y espccics. Para cada L-\pceir- \L' proporcionan rel'erencias bibliogrirficas. inlbrnraci6n sobre t:l tipo, sincininros, i'poca dc floracirin y lipo dc vegctaci6n.Se proscnta la distribucitin illtitudinal para Sonorl, la distribuci6n gcogrifica. y Ios cspccitnenesreprcscntados para cadl especie.Para algunasespecies se ap()nan notas s()brcusos, problcmas taxon6micos y nomcnclaturales.y se discutenotros puntos de inter6s. Pallbras clave: Euohorbiaccae.M6xico- Sonora.

INrRoDUCrloN Juss., and Euphorbia spp.l. This publication is an ac- count of all the Euphorbiaceae species native or nat- The Euphorbiaceae constitute a large and diverse uralized in the state of Sonora, M6xico (Fig. l). assemblageof 311 genera and about 7,500 species Although a political border is not necessarily an (Webster 1994). The family has a nearly cosmopolitan ecological boundary, it serves the purpose of con- distribution, but the greatest diversity is by far in trop- taining a study. However, the borders of Sonora are, ical and subtropical regions. In addition to its great to varying degrees, biologically significant. Most of floristic importance, there are a number of economi- the western boundary is the sea. The east boundary cally important members. Among these are the Rubber is close to the continental divide. The north boundary Tree LHevea brasiliensis (Willd. ex A. Juss.) Miill. marks a division between the better-known continen- Arg.l, Cassava fManihot esculenta Cranrzf, Castor tal flora of Arizona and the relatively poorly known Bean LRicinus communis L.], and numerous ornamen- flora of northern Sonora. The Sonora-Sinaloa border tals lAcalypha spp., Codiaeum variegatum (L.) A. separates a continuous flora but is far enough south Steinmannand Felger ALISO

Sanluls BfoGolorar CabezaPrieta WildlifeRefuge ---*./////.////w7rt7 0 100 Km 200 ElPinacate and-<4i1i111 0rgan-PipeCactus # GranDesierto deAltar.,r""f NationalMonument

- AltoGolto de (kao Californiay Delta delRio Colorado Puarto-4\ Rrhia r / SienaSan Luis Pefiasco i^--,- '.- f banJorge \ Jan0s

i,''.J,J't -."..,; &visOe ,,i Fl \/,oin j Siena Ana i Jlellas't f'(- 1i buenos 'r.. ii. Laeur$i :i ec SierradeI i Aconchiifrcterrt{i ,"'i:ig i '6 ,..'...j \- "'-.iE PuntaCirio\i.r (SierraBacha)\." /t '!.2 ig ;S / i: i(' l= Ures ii .;6.J{ ii i=\ Sierla.lvlazaldnil i=i sS ;.,. ti iE\ i lslaTibu16n i"'j "i" i! i';\EiE\F lslaSan o ------r I r'1 i' i i Esteban ," ji"'^..", '^.^ ^ F:\- i Y6cora"'l 'i"!i SierraLibre Sierra" San"" :';'r Javier/ElAliso SienaEl Aguaje iiSierra i. ElBacatete lslaSan\ t\.j PedroNolasco Guaymas Cd.0brag6n

Bahiade Lobos

LasBocas

Fig. l. Sonora, Mdxico to include the northern limits of the tropical Mexican river systems originate in the state, e.9., the Rio So- flora. noyta and Rio Sonora. The eastern miugin of the state Sonora encompasses 185,43I km2 and is the second is comprised of numerous north-south trending moun- largest state in M6xico after Chihuahua. It is topo- tain ranges forming the western cordillera of the Sierra graphically and biologically diverse. Three major river Madre Occidental. The highest elevation is 2,625 m in systems, the Rfo Colorado, the Rio Yaqui, and the Rio the Sierra de los Ajos in northeastern Sonora. The Si- Mayo, course through the state and empty into the erra San Luis in the extreme northeastern corner is Gulf of California. In addition, several other minor nearly as high, and another high peak, further south VOLUME I6. NUMBER I Euphorbiaceae of Sonora 3 on the Chihuahua border, near Mesa Tres Rios may be Table l. Number of native gencra and spcciesof Euphorbiaceae equally high. Numerous other ranges, generally de- in Sonora compared with other North and Central American regions. creasing in peak elevations westward, spread across Size Corr the rest of the state, interspersed with broad valleys Nrli\e Nati\e pared uith Region Specie\ Genera Sonora and expansive plains. Sonora includes the northern limits of tropical and Sonora l;10 r8 Calitbrnia subtropical biota as well as some of the most arid des- (Webstcr 1993h) .14 efi regions of North America. The total annual precip- tsaja Califbrnirr (b()th states) '71 itation decreasesfrom south to north, and east to west, (Wiggins1980t t2 0.8 and increases with elevation. The rainfall is largely Arizclna (Kcarncv biseasonalwith summer and winter-spring rainy sea- and Pcchlcs 1960) 78 l3 1.6 Ncw Mcric

1992; Turner et al. 199-5).Total annual precipitation (Correllantl Johnstonl97O) l)9 Iu 1.O varies fiom roughly 85 mm or less near the delta of Nucra Cialicia (McVaush.pcls. conrnr..1997) ca. l-10 o.1 the Rfo Colclrado to more than 1000 mm in portions ( iuiltcllralir of southeastern (Felger Sonora and Wilson 1995; Yet- (Stantilcy lrntl Stcvcrrrrarkl9-19) 13.1 1.1 0.6 man et al. 1995). Human pplants are often washed with sea water versity present.Most of the taxa in Sonora are native, during high tides. Euphorbia platy*sperma may extend and we believe that only three species are definitely onto the upper beaches but well above the highest not native. These are Euphorbia hvpericifulia, E. pep- tides. A substantialnumber of speciesoccur on coastal lus, and Ricinis t'onttnttnis. A few other species, e.g., dunes. Euphorbia leucophylla ssp. comcactcorum is es- E. prostrata and .8. serpens, may not be native, but we sentially restricted to coastal dunes and sometimes oc- are uncertain. curs on upper beaches. A number of other euphorb In comparison with adjacent areas to the north and species that occur on coastal dunes are also found far- west (Arizona, Baja California, California, New Mex- ther inland, e.g., Croton califoruicus, Jatropha ciner- ico), the Euphorbiaceae are quite diverse in Sonora. ea, Euphorbia eriantha, E. petrina, E. platysperma, and polycarpa. This is due to the more tropical affinities of the flora. E. As one moves further south in M6xico and Central Tropical deciduous forest (TDF).-The northern arm America, the diversity of Euphorbiaceae continues to of TDR sweeping northward from the tropics, ends in increase. Table I compares the number of native gen- the mountains of eastern Sonora and southwestern Steinmannand Felger ALISO

Chihuahua. Sonoran TDF is sandwiched between strong seasonality linked with monsoonal rains and are thornscrub to the west at lower elevations and oak for the most part highly frost-sensitive. Unlike TDE zones eastward at higher elevations. Northward, along wholly natural tropical thornscrub generally does not the east side of the Sonoran Desert, TDF merges into form lOoo/operennial coverage. The stature of the non- an inland thornscrub (Felger and Lowe 1916).In TDF riparian trees is lower, and the leaves generally smaller the trees generally overtop the ccllumnar cacti, while than those of the TDF. Thornscrub in Sonora supports in thornscrub the columnar cacti overtop the small 46 euphorb species(32Vo of the total euphorb flora). trees and shrubs (Gentry 1942). Undisturbed TDF in Twshrub- cany()ns. Sebastionia puwtniana and Croton atif. ni, by or semiarborescentscrub with a nearly ckrsed can veus 'drethe other two trees commonly fbund in TDF, opy of small trees and large shrubs. Thornscrub ex- but usually occupy relatively dry hillsides and are of tends northward along the easternside of the Sonoran much smafler size. Acalv-pha cincto, Cnttotr ulamosan- Desert like the tail of TDF narrowing in geographic us, C. t:iliotoglandulifer, C. .flavescens.Dituxis nun- width and elevation. Nrlrthward it gives out at about zunilloana, Eu1;horbia colletioicles, Jcttropha rnalac'o- the vicinity of Arizpe, where elevationsrise and winter phvlla, and Manihot aes(ulif()lia are characteristic fieezing as well as drier conditions become pro- shrubs. Dalechompio s<:anden^sand Tragia sp. are fre- nounced. Prominent euph()rb speciesof inland thorn- quently encounteredvines. The monsoonal rains sup- scrub include Aculvpho popillosa, Crtton ciliatoglctn- port a large number of annuals.The more common of duliJer, C. .fluvescerts, C. sonoroe, Euphorbia colle- these are Aculvphu olienu, A. rytlvstat'h,-o,Euphorbia tioides, Jotrutlthu (()rduto, and Manifutt angustiloba. heteroph,-llu, E. cwtthophrtra, and a number of mem- bers of Euphrtrbiu subgenus Agalomu, including E. Srnrtran Desertscrub.-The Sonoran Desert. defined grantirteu, E. .sonrtrue,E. ot't'ttrttiderr,and E. diosL'o- and elegantly describedby Forrest Shreve ( 195I ), cov- reoides ssp. lttenultu. ers roughly the northwestern two thirds of Sonora. Shreve divided the Sonoran Desert into seven geo- Thornscrub.-Thornscrub in M6xico is of tropical or- graphic vegetation zones, five of which occur in So- igin, where it might best be called tropical thornscrub. nora. As mentioned above. Shreve's Foothills of So- It is essentially a drier version of tropical TDF and nora zone is essentially thornscrub. The other major intermediate between TDF and desertscrub. The areas of the Sonoran portion of the Sonoran Desert boundaries are fuzzy. Like TDE the plants show a include the Plains of Sonora and portions of the Ari- VOLT]ME I6. NT]MI]ER I Euphorbiaceacof Sonora zona Upland. the Central Gulf Coast. and the Lower the Sierra Madre Occidental and Sierra Madre Oriental Colorado Desert. Within the span of environments in and extending into adjacent inland areas of the south- the Sonora portion of the SclnoranDesert there is great western United States. At its northern limits freezing variation in vegetation cover and structure, and the weather is much more severethan in the SonoranDes- number and kinds of speciespresent. Arbsubshrub species are Aculvltha <'ulifornictt, Cnttort sti(|().rl)()ru,JuIrtt1thtt trtut ntrhii.tt var. septem/ida, Tra- califrtrnicLr.s,C. sonortte, Ditaxis lanceolata, Euphor- .qiu rteltetilltliu vitr. di.s.sectu,and L ront().ru. bia tomentulosct, Jcttropha cardioph,,-llo, J. (unedtu, Sebastiania biloc'ularis. and the less ofien encountered Ortk x'otxllurrrl.--Oak woodland vegetaticlnis widely Adelia spp. Herbaceous euphorbs are fiequent and distributed at ele','ationsabove desert,grassland, thorn- widespread,and the Sonoran Desert is a strongholdfilr scrub, and tropical deciduous firrest. but below pine- diversity plant communities is often only majority of euphorbsfiequent in S

Bernardict cinerea, Euphorbia leucophylla ssp. com- caacorutn, and Euphorbia pediculfera var. linearfolia are probably truly endemic. Both Euphorbia alatocau- /i.s and Euphorbia chiribensis occur close to the Chi- huahua border and probably will also be found in that state. Similarly, Croton subjuncundus might occur in northern Sinaloa. Although many species may be locally rare and known from few collections in Sonora, most of these are common elsewhere, and only a small number of Sonoran Euphorbiaceae appear globally rare and./genus to genus. The ma- as of 1995, wherever possible to help place the col- jority of descriptive terminology used in this paper is lection localities (see Fig. 2). We have seen all speci- general; specialized terms for the Euphorbiaceae are mens except those specified as "not seen." Unless oth- Steinmann and Felger ALISO erwise indicated, specimens are from Sonora and de- tion date seems significant, such as types or otherwrse posited at the University of Arizona Herbarium historically interesting specimens,both the collection (ARIZ); specimens in other herbaria are indicated by number and date are given when available. The her- the abbreviations given in Holmgren et al. (1990) with barium accession number is provided for type speci- the exception of the recently formed herbarium of the mens and when necessary to avoid confusion. Universidad de Sonora in Hermosillo (USON). If a When appropriate, references are provided for cer- specimen is at ARIZ, we generally do not cite dupli- tain genera. The following references are useful for cates at other herbaria. Similarly, if we have seen a many species in a number of genera: Miiller 1866; holotype or lectotype, we do not cite isotypes or iso- Standley 1923; Wheeler 1960; McVaugh 1961, 1995; lectotypes.When a specimen lacks a collection num- Wiggins 1964, 1980. The reader is also ref'erredto ber, it is identified by the date if available to us, fbr Pax./Pax and Hoffmann's treatments in Das Pflanzen- example: 30 Oct 1982, Ezcurra s.n. When the collec- reich IV 147.

'fHE KEY TO GENERA

I. [-atcx prcscnt; flowers encloscd in a cuplike or slippcrshaped involucre of'gland-bearing,unitcd bracts,the whole structurcsirnu- lating a hiscxual flower by posscssinga sinele. ccntral ? flowcr that is surrounded by scvcral to lnany rJ llowers: d flowcr consisting of a single, naked pcdiccllilt!-strnrclr: ? flowcr consistingof a single. nakcd pediccllatcpistil. 2. Cyathiunr spurrctl.str()ngly zygonrorphic: glantis c'nckrsedby the cyathiurn: stcnrsthick. green or grayish. antl strcctrle-nt . I'tlil,ttttltut 2' Cyathiurrrnot spunccl,

leaves and bractsl ? sepals 3 5. with or nithorrt stipitatc glancls; stylcs. il-unitcd. thcn onlr rrl rhc hlrsc anti ll-cc irhore: stigmas n()t pcltate. 5. l-eitvcs strongly peltatel stipulcs unitcd arrtl sun'ounding thc- huds: stilr)lens nurncr()us. tlrscicrrllrtc rarrrihccl. each bcaring many anthers:ovarics and capsulescchinilte . Ricirtu.s 5' Leaves not pcltatc (rriay appearslightly pcltatc tn Muniltot sp.); stipulcsn()t ur)itcdarouncl tlrc butls: stanrcnslO or lc*cr cach with a single anthcrt ovarics anclcapsules sn)ooth (glabroLlsor pubcsccnt). 6. Milky latex abscnt,thc sap watery, clear or cokrred: petals prcsent . .l,ttt"1th,t 6' Milky lrtex present;pctals absentbut the calyr son)etir)respetaloid 7. Inllorcsccnccsspicilirrnr; ? flowcrs bornc on an clongatcd pcdiccl; d flowcrs hishlr rcducccl.*ith a singlc scpal wraping around a singlc stamcn l)ulentbtrtitt 7' Inflorescenccscymosc, paniculate.or racen)ose;? flowers subsessile:rj flo*crs not highlv rctlucctl. rrrostl\ with 5 scpalsand 8-10 stanlcns. ti. Hcrbagc and capsuleswith stil'l'.stinging hairs, leaves relativclv shalloulr. lobetl. thc dirisions lcss than hall'thc blatic: at lcast sorrreol-the stamensconnate Crtidttstttlu.t 8' Herbagc and capsulesglabrous or pubescentwith sofi, nonstinging hairs: leavesdccply krbcd. thc divisron: morc than half the hladc: stanrcnsfrcc Muttiltol 3' Leirvesnot palmittcly lobed (long shootsof Benutrtliu t inerea somctimcs with palrnatclytrilobcd lcavcs but the others unlobed) or if palnratcly lc>becl(T'rugiu lut irtiuttt). thcn evidently conrpound. 9. Staminateand ? flowcrs in axillary lasciculateclusters 10. Large trccs; leaves -5 or more cnr long: stylcs capitate; fiuits drupaccous. I sccdcd l)rrpete.s l0' Herbs or shntbsl leavcs 0.8 ,1.5crn longl styles filifbrml fruits capsulal 2 6-seeded. I l. Shrubsl leavesexstipulatc, mostly fasciculateistarnens 3 6l stylcs laciniatcl ovulcs solitary in each cell of-the ovary. theseeds23perfiuit:seedsspherical ....Adeliu ll'Shrubsorhcrbsl leavesstipulate,alternate;stamcnsca.8-17:stylesoncedivided:ovules2ineachcclloftheovary, thc seeds 6 per f-mit; seeds trigonous Phyllanthus 9' Staminate and ? flowers variouslv arranged but not in axillary f'asciculateclusters. 12. Ovules 2 in each ccll ofthe ovary, the seeds6 per fruit; plants without latexl leaves entire; pubescenceifpresent of unbranchedhairs only. 13. Herbage, ovaries, and capsules dcnsely glandular-pubcsccnt; d flowers with petals . . . Andrachne l3' Herbage, ovaries, and capsules glabrous: d flowers without petals Phyllanthus 12' Ovules solitary in each cell of the ovary; seeds 2 or 3 (.1) per fruit; plants frequently (but not necessarily) possessing one or more of the fbllowing traits: with latex: leaves toothed; pubescence malpighiaceous, stellate, or lepidote. 14. Indumentum (at least in parr) stellate or lepidote. 15. Herbs, shrubs, or trees; pubescence of either stellate or lepidote hairs; leaves entire (only toothed in Croton martinianus, but this an herb)i inflorescences bisexual (except in dioecious spp.): d flowers usually with petals, VOLUME 16.NUMBER I Euphorbiaceae of Sonora

the stamens inflexed in bud. the anther tips pointing downward and infolded against the base of the fllament: \eeds ( arun(ulatc Croton l5' Shrubsl pubescenceonly of stellate hairs: leaves toothed; inflorescencesunisexuali d llowers without petals, the stamens erect in bud, the anther tips pointing upward: seeds ecarunculate Bernardio l4' Indumentum lacking (i.e.. plants glabrous)or of unbranchedor malpighiaceoushairs. 16. Pistilfate llowers (excepl in A. cittt ttt and A. .filipes\ enclosed or subtendedby a toothed or lobed. foliaceous, accrescentbract: anther ce'lls elongate and narrow. oficn flexuous-vermiforml styles n.rultifid with many filiforn.r segments Acalt'pha l6' Pistillate flowers not enclosed by such a bract: anther cells globose or oblong. not flexuous vermifbrm: styles entire or hifid. rarely laciniate. 17. Flowcrs with pctals: plants without stinging hairs or nrilky latex; malpighiaceoushairs ofien present. 18. Hcrbs or shnrbs. 2 nr tall or less; puhescencc (cxccpt in I). uderutplurrzrand 1). .\erratd var. californicu). at lcast in part. of nralpighiaccoushairst olary (cxccpt in I). .scrruluvrr. californicu) pubescent;petals tlistinct: sccclslcss thrrn(r rrnr krng. sculpturcd . . . . . I)itaris lli'Shlrrhsorsnr:rlltrccs.oftcnnrorcthan2rrrtall:!llabr()usoruithunbranchedhairsonly:ovaryglabrous; Q l)L'lirl\ ( ('nnirlr': rt'r'.ls rtt tllr)le llllll l()llS. \lllilr)lll .ldtr()phu l7' [jlo*ers uithout pctals: plants son)etillcs *'ith nrilkl'latcr and sorne with stinging hairs ((ilrlo,icrt/r.r:rnd 'l rttqittl. hirirs nol rrralpiuhi:rccous. 19. Annuals or herhaccous percnnials. sorrrctinrcsslightly'uoocly ilt thc bllsc. lO. Plants rvith ntilky lirtext hcrbagc glirhtru:: flo*crs not ()lr articulatc(l pcdiccls: st:uncns two: scssilc glantls prcsent at th!- bilsc of thc 'r lloucr bractsl -l hornctl gynobasc persisting alier dchiscence ol tlrc frLrit . . . Srillinxiu lO' Plants rvithout lnilky later: lrcrbrrgc rr ith hrrrsh. olien stirtging hairs: flttwcrs ()n articulatcd pcdiccls; (hut st:lllcns J 6 (rarcly nrorc): glantls n()t l)rcscnt at hasr'ol thc ? flou'e-r bracts sonrctinrcs with 'l'nt,qia an inrlumcntunrol' stipitatc glarrtlsll.l hornctl r\ nohasc lackinc l9' Shrubs.wootly wcll abovc thc brsc. 21. Lcavcssubfirscicrrlatc, cntirc. cglanriLrlar: snle burnchcslacirtiatc tlrcir uholc lcngth ...... Adeliu 2l'Leaves llltL-rnatc.cntirc ()r scrrute(s()rlctrrncs srrbtlrsciculate in.Sllrrr.rtlalltr bttt thcn thc lcavcs scrrateancl glands pre-scnttrt thc brrscol tltc blirtlct: strlc hranchcsctttirc or bifid. if laciniatcthcn only at the apices. 22. tlcrbagc with stitT,stinr:ing hairs l.(r 7.5 tttttr lonl . ('nidtt.ttttlu.v 22' llcrbagc glabrousor pubcsccnlrrith nonstin!inghrrirs nl()stl\ lcssthan I trrnrlong. l-1. Plantswithout ntilkv latcr: lcirres tlcnsclr cincrottsptthcsccnt. lhc llunina obscurcdby the hairs:s(anrens ca. lO: st1'lcbranchcs *ith laciniatctips: capsulctlcnscly puhcscent

l3' Plantswith milky latc*, ,"r,r", glatrrorrs.r sparsell'pubcsccnt thc-lanrina t,r,nt" rnllrt[,t"t"t' thc hairs: starnensI -i; stylt' brattchcscntire: cttlrsulcglabrtlus. 2:1. Lcavcs palmiveinecl,coarsclv and irrcgularlv toothcd. sornctintesentire. thL'trtargins oftcn ciliatc; ? llowcrs antl fruits pecliccllatc:iJ Uowcrs with a single starllen

lJ' Lrrrvcsp"nnirein".i. h,,,'i, r*r,,,," thcir t,,talleri:th- thc rrr:rrgin,gt,,nr,,,,r, ,/)fu'lt"li" and fllits sessilc: d llowers with more than one stanrcn Sebuslittttict

ACALYPHA L. flowers usually subtendedby bracts that enlarge and envelop the ovaries and capsules; sepals 3 5, much Annuals to perennial herbs, shrubs (or elsewhere shorter than the ovary; petals 0l ovary mostly 3-loc- rarely small trees); mostly m()noecious.Latex absent. ular, with I ovule per locule; styles 3, fiee or basally Pubescence(in ours) of unbranchedhairs, sometimes connate,laciniate. Seedsmostly ovoid (ours), caruncle glandular. Leaves alternate, often long-petiolate, den- minute or absent. Many Sonoran species possess un- tate-serrate,palmi- or penniveined. Inflorescences uni- usual, l-carpellate flowers and fiuits at the apices of or bisexual; d inflorescencesspikelike, mostly axillary some pistillate spikes, which following Radcliffe- but frequently a terminal extension of the ? inflores- Smith (1973) are termed allomorphic. cence; 9 inflorescences racemose, fasciculate, to pa- Tiopical with a few temperate members; widespread niculate, but usually axillary or terminal spikes. Sta- in the Old and New World; 450 species. Probably minate flowers minute, with a 4-lobed calyx; petals 0; more than 70 species in M6xico. Twelve species are stamens usually 8, filaments free, anthers characteris- recorded from Sonora, and two others are found very tically pendulous and flexuous-vermiform. Pistillate near the border and might occur within the state.

l. Shrub: all ? flowers long-pedicellate and 3-carpellate: ? bracts minute, not green and fbliaceous nor divided into narrow segments '''" A filiPet l' Shrubs or herbs: I flowers sessile or if pedicellate then these allomorphic and at the inflorescence tip, the proximal ? flowers regular and sessile: I bracts usually fbliaceous or divided into narrow segments (rninute only in A. cincta). l0 Steinmann and Felger ALISO

Shrubs. 3. Pistillate inflorescence densely stipitate glandular. 4. Leaves mostly ovate: ? inflorescencesusually less than .1 cm longl ? bracts usually crowded and obscurrngthe rachis. the central tooth not elongated A. Lttlifbrni<'tt 4' Leavcs often more lanceolatethan ovatel ? inflorescencesoften more than 4 cm longl ? bracts usually wcll spacedand not obscuring the rachis, the central tooth olien clongated A. .sLrbt,i.st.itlu 3' Pistillatc infloresccncenot stipitateglandular, if any glanclspresent, these restrictedto thc margins of the bracts. 5. Largest leavcs niostly ntore than l0 crn long. thc unclersideof thc blade often wrth a paler-coloredn)argin: ? bracts less than I mm long, not cnveloping thc fiutt A. (Uj(tu 5' Largest lcaves mostlv less than l0 cnr long. the undcrsidc of the hladc lacking a paler-colorcclnrargin: ? bracts rnore than 2 mm long. cnveloprng the tl'urt. 6. Pistillatc hracts cvenly and crenatelyt()othed. thc ca. l5 2l teeth less than l/-5 as long as the bract A. Lulifornitu 6' Pistillatc hracts ircgularly and coarsely toothed. at lcast sonrc ofthe ca.7 l3 tecth l/3 t

ir\ the l:rlcr;ll l('ctll \. tt( t)tttL \it Lttttt

Aca,lypsR ALrrrNABrandegee, Proc. Calif-. Acad. Sci. This species is a common understory herb of the ser. II, 3: l'72. 189l.-TYPE: M6xico. Lower Cali- tropical deciduousforest in the southeasternpart of the tbrnia [Baja Califbrnia Sur], San Jos6 del Cabo, Sep_ state.While most of the specimensfrom this areahave Oct 1890,Brandegee.r.r?. (holotype UC[#109873]!). long, spreading hairs on the lower stems, there is a gradient to plants completely lacking these hairs (e.g., Acultplu sintJtlit'issinlr:'Millsp.. Ficlcl Mus. Nat. Hist., Bor. ser. 2: Gentrv 1613). All of the Baja California specimens ,117( ,l l8). l916.-TYPE: M6xico, Yucatain.Progrcso. in a shady examined, including the type, lack long, spreading ccrppice,(iaunter 1/82 (holotype F[#,+3825-5].nor secn. phoro hairs. There is also variation fField Mus. neg. 5259 I ] !: isotypc NY !). in the allomorphic fiuits; well-developed lateral circular projections often occur, Erect summer annual; July-October. Shaded or ri- but these can be lacking. parian habitats in Sonoran desertscrub,thornscrub, and This species and A. neomexicana are very similar tropical deciduous forest; 75-500(-900). Central and and undoubtedly closely related; the relationship be- southern Sonora, from the vicinity of Hermosillo near- tween them should be investigated further. In addition ly to the Sinaloa border. Baja California Sur and south- to the somewhat subtle morphological differences giv- western Chihuahua to at least as far south as Oaxaca en in the key, A. aliena usually possessessubstantially in western M6xico and also in Yucatiin and Nicarasua. more allomorphic flowers than does A. neomexicana, VOLUME 16.NUMBER I Euphorbiaceae of Sonora t1 and the herbage of A. neomexicana in age tends to branches or the lateral branches sometimes as large as become suffused with bright red coloration, a condi- the primary stem when growing in dry, sunny habitats; tion not observed in A. aliena. Also. these taxa have internodes 19-28 mm long towards base, decreasing different elevational distributions. Ac'ulypha aliena oc- in length towards the ends of the branches; leaves pri- curs from 75 to 500 m (with one collection at 900 m) marily alternate, those of the lower 2 nodes often op- in thornscrub and tropical deciduous firrest. while A. posite or one leaf of the pair reduced or failing to neomexicanaoccurs fiom 800 to 1700 m. primarily in develop; stipules triangular to triangular-subulate,ca. oak and pine-oak woodland. I mm long, hispid; petioles slender,3.8-7.6 cm long, ofien longer than the blades; blades ovate, 6.1-'7.2 cm 9-l Mpio. Alanros: Chorijoa. Gtntry l6l-1. Alalros. Stt,irtrrtttttrt 22-1. long, 3.9 4.4 cm wide, moderately bicolored, cuneate Agua Salada.27"l5'N. l0U";1(r'Wl .\ttirtntrutn 9.1 11.5. Mpio. Hcr- ntosillo: l6 mi S of Hcrntosilkr ort rtl 1o (iuuvrrras. ll'l,q.qirr.r<( Rol to nrunded at base, palmately 3(5)-veined, the central lins 191. Mpio. C)nar.as:Agua,\rrrarilla ([-os I)initos). l5 krrr WNW vein pinnately branched, sparsely hispid on both sur- of Tcp

C'HIlit.\ltt,A. (iUirsarcnr0s.clillv()n. O<'rttrt )121. intermixed with hispid eglandular hairs, the adaxial surtace essentially glabrous, the marginal teeth (5) 7 Acalypha burquezii V. W. Steinm. & Felger, sp. or 9. deltoid or sometimes very shallow, the central nov.-TYPE: M6xic<1,Sonrlra, Mpio. Sahuaripa,El tooth largest with lateral teeth progressively smaller; Victor, on the Rio Mulatos, ca. 3 km E, of Mulatos, I sepals3 (sometimesinconspicuous and appearing 28"39'40'N, 108'43'15'W 920 m, l3 Oct 1994.Fel- absent),broadly subulate,0.3-0.-5 rnm long including ger & Bfirquez.94 396 (holotype Ariz[#3-]5,1691;is- the hispid-setosefringes, scarious-membranous;styles otypes DAV MEXU, NY, RSA, USON). Fig. 3--5. 3, the divisions entire and papillose towards the base, faciniateat the apices.1.6 2.1 mm long, greento pale Annulr. l2 35 cnr lrlta.nrdir non prol'unda,pilis incurvatisvcl yellowish or reddish; ovaries and capsulessetose-his- hispitlis.pili trstluc1.2 rrnr longi: lirlia pleruruqrrealtcrna: stipulac pid, the capsules3-lobed, ca- 2 mm in diameter; ped- trirnguliltilc vcl triilnlrLrlilt()suhrrlatac. ca. I rnnr longac; pctioli gra cilcs.l.t'i 7.6 cnr longi: Ilrnrinacovutac.6. l-7.f crri longae.-j.9 7.2 icellate allomorphic flowers terminating the ? spikes, cm latae.c basi 3 r'el 5-ncrves, basi cuneatacvcl rotunrlatae.lpicc the pedicel l.l-2.8 mm long, the ovary 0.8 1.2 mm brcr"itcracunrinatac: ruarginc serratae vcl crenato-serratae;spicac 11 wide including a pair (one on each opposite "face" of axillarcs rclativc inconspicuac.0.35-1..1 cm longae: llorcs d arctc the ovary) of broad, cup- to plate-shaped nearly entire aggregati,0.5 0.7 nrnr lati, cremei. pedicelli 0.4 0.5 mm longi: spi- to denticulate wings or the ovary not winged; seeds cac ? Iermintrlesvcl axillares, 1.7-6.5 cr.nlongae, ca.5 6 nrnr latac: bracteaeusquc 36,2.5 .1.5mm k:rngac,3.5 ,{.5 rnm latac,cupulatae. plump, broadly ovoid, 0.9-l.l mm long, 0.7-0.9 mm flabellatae:dentes (5) 7 vel 9. plerumque deltoideil scpala ? 3. latc in diameter, red-brown, covered with a thin and iri- subulata.0.3 0.-5nrm longal styli laciniati. 1.6 2.7 nrnr longi. pap- descent-lustrouswhitish coat when mature, shallowly illosi basem vcrsus; capsula J krbata. ca.2 mm diarnetro: scnrina reticulate-fbveate, the fovea concave, in longitudinal late ovoidea, 0.9-l.l mrn longa, 0.7-0.9 rnm diametrtr. retieuattr- rows, less than 0. I mm wide. fbveolata. Appearing with the summer rains, mostly an under- Erect to decumbent annual, mostly 12-35 cm tall growth herb but sometimes also in more open areas; and from a shallow root, herbage with a sparse to pine-oak forest, oak woodland, and the uppermost dense indumentum of short, mostly incurved hairs in- margin of riparian tropical deciduous forest in east- terspersed with sparser hispid hairs to 1.2 mm long; central Sonora at92O to 1460 m (to 1800 m in adjacent primary stem well developed, with short lateral Chihuahua and 1980 m in Sinaloa). Documented for Steinmann and Felger ALISO

.,.:-:1:,:.;i l,-- ,'lt,t\,(

-o::\ ,.,4.,r,.'

!

l/ ll^ \\, ,('i', lmm (i'\t V

Acalt'pha burqueiii.3. Habit. 4. Pistillate bracts and allomorphic flower. 5. Seed. All frorn Felger & BurqLte:.91 -196. VOLUME 16.NUMBER I Euphorbiaceae of Sonora 13 east-central Sonora in the vicinity of Mulatos and east In southern Sonora, Acall,pha californica appears to of Y6cora near the Chihuahua border, also in nearby intergrade with A. subviscida. Two collections (Sand- western Chihuahua in the vicinity of Nabogame and ers 9466 & Martin s.n. l2l Aug 19901)from the vi- northern Sinaloa in the Sierra Surutato. cinity of Cerro Las Tatemas near Alamos appear to This species appears to be related to Acalypha neo- have characteristics of both species. The leaves are mexicana, from which it differs by the papillate style more or less lanceolate and thus reminiscent of A. sub- bases, less conspicuously viened and fewer-toothed viscida, but the bracts, although relatively well-spaced, pistillate bracts, and pedicellate allomorphic flowers. are particularly large for A. subviscida and lack the It is named in honor of Dr. Alberto Brirquez, of the frequently encountered elongated central tooth of that northwest regional division of the Centro de Ecologia species. In these latter two characteristics, the plants of the Universidad Nacional Aut6noma de M6xico in resemble A. californica. Although A. .subviscida is Hermosillo, Sonora, who has made major contribu- common in tropical deciduous forest, Cerro Las Tate- tions to the conservation and ecolclgicaland botanical mas is the only known tropical deciduousforest station knclwledgeof the Sonoranregion. fbr "true" A. califttrnicct (e.g., Steinmann 94-153). The placement of these intermediatesis unclear, but Purdt\'l)(.\. Mpio. Sahuaripa:PLlcl'to EI Victor. ca. 2 krn E ot'Mu they may represent hybrids between A. caliJbrnica and lattrs./'r'1gal c* Iltirqut:91191:1.6 knr S ol'Mulatos, ctny()tt. lu 3u'lO"N. 108":15',12"W.I.-rlger & Biln1ue:. 91_7-11. Mpio. Y6 A. subviscidc.These two speciesare otherwise usually cora: Aroyo Hondo, ll.5 krn E of IJI Kipor,.l ktn W of Chihuahua spatiafly separated with A. t'alifornit'a in desertscrub b

Kuntze.Revis. Gen. Pl. 2: 6l'/ . 189l.-TYPE: M6x- N{pio. (icn. Plutilrc() E,lfas C'alles: 2.(r trri W of Sottovtit on MEX 2. ico, Lower Calilornia IBaja Califbrnia Sur], Mag- I' t l,gt r,\61 ().1. Mpio. Ciuayrnas: (iuaytnas, | 88J . I' u I nrt r 261 ( LIC ). dafenaBay, Oct Nov 1U39,Bart'lay 3/38 (lectotype M1rio. Alaruos: C'crro [-as Tittcrl)as. Slt'irtrrtcttttt91 l5-]. Mpio. Hua- BMI#5106701!.designated by Levin 1994,p. 263). tabirnrpo: |.5 krrr NW of C'anrahuiroa on thc rtl t() [,ils B()clts. .\t('lr?- trturtn 9-l -166. Acaltpfut ltrin.qlti S. Wrtson. Prcc. Antcr. Acad. Arts l0: l7-1. 1885. TYPE,:M6xico. Sononr.ll50 nri S ol thc l]nited States Ac',qr-rprrecrNc'lA Miill. Arg., Linnaea 34: 20. 1865. borderl. ravines, shorc ot thc Culf of Calitirrnia. 29 Mar llJ8.1. Ricinocarpus t:inc'tus (Miill. Arg.) Kuntze, Revis. Pringlc .s.n.(holotype CiH!.t. Atultphu.stokesiue Ias.ilolie.iiiI Pax & K. Hof'tln.. in Das Pflanzcrt- Gen. Pl. 2: 6l'7. 1891.-TYPE: According to the 'l'YPE: reich IV 1.17.xvt lHeli 851: 138. 192.1. LlnitcrlStatcs. pnrtologue, "In Mexico (Pavonl in hb. Boiss.)." Clalilirrnia,San Dicgo, ,S/okess.n. (according to Lclin llt)t);I. p. This specimen,the holotype, is now at G-BOIS (not holotype at B has been dcstKrycrl ancl no isotypcs arc seen) and is surely a Sess6and MoEiflo collection. i::i:T At'ultltlttt Standl..Ficld Mus. Nat. Hist.. Btx. scr. 22: 3.1. Small shrub to L5 m tall with slender,woody stems, 3crlnl 19.10. TYPE: M6rico. Chihuahua. El Linrtin. 3(XX)ft. 2-5Julv the herbageofien glandular and viscid; reproductiveat 1935. (jorrn /.5J(/(holotypc F[#u0995ttll). various seasons.Sonrlran desertscrub, thornscrub, and rarely arid slopes in tropical deciduous forest; near sea Drought-deciduousshrub 2-4 m tall, notable in pos- level to 870 m. Extreme northwestern Sinaloa through sessingleaves that usually have a distinctly paler mar- western Sonora to southwestern Arizona; Islas Tibu- gin and in possessinghighly reduced pistillate bracts r6n, San Esteban, and Turners; and the Cape Region that do not envelopethe fruits; mostly July to Novem- of Baja California Sur to southern California. ber. Riparian habitats in tropical deciduous forest in Wiggins (1964, p. 197) treated the nearly eglandular southeasternSonora; 230-800(-l100) m. Also south- populations fiom the vicinity of Guaymas southward western Chihuahua southward at least to Guerrero. a species of southern M6x- as Acalypha vagans Cav., Mpio. Alamos: Cair6n las Ardillas, side canyon on the E side of Rio ico. The tendency towards eglandular herbage and Guajariiy,ca. 2 km upstreamfrom Los Aguaros,27'39'N 108"58'W slightly larger leaves do not appear sufficient to war- Felger 91-72: Siena Saguaribo, Tepopa, NW of Chiribo, 22 Aug rant separation from A. calfornicc. Such characteris- 1.992.Martin et al s.n. tics are expected in the more mesic habitats where these populations occur. In A. vagans the pistillate AcelypHa FILIeES(S. Watson) McVaugh, Brittonia l3: spikes are strictly axillary, but the Sonoran plants have 149(-150). 1961. Corythea filipes S. Watson, Proc. terminal as well as axillary pistillate spikes. Amer. Acad. Arts 22: 451G452). 1887.-TYPE: l4 Steinmann and Fclger ALISO

M6xico, Jalisco, Barranca [9 mi NE of Guadalajara], indica by being more delicate, by the possession of June 1886, Palmer 90 (holotype GH!). pistillate bract margins that are crenate (vs. shallowly repand-dentate),and by shorter pistillate inflorescences A<'alt'phacoryloide.s Rose, Contr. Ll.S. Natl. Herb. l: 357(-35g). that are borne in the axils of nearly 1895. TYPE: M6xico. Colima, Manzanillo. | 3l Dcc 1890. all of the main- Pttlmer lSll (lectotypeUSI#907561!. here dcsignatetl).Rose cit- stem nodes. In light of no evidence suggestinga close ed two colfections in the protologue.the othcr betng pulntt,r l36g relationship between the Old World and New World (US[#.16890]!). We clesignatcthe nrorecomplcte specintcnas lec- plants, we believe that this taxon is best treated at the totype. rank of species.

Shrub to 2 m tall; May and December, so far as ('utHL,rsr,q.Mpio. Tentosuchic:Nabocarlc. l8.30'N. 108"30'W. known. Tropical deciduous fbrest in southeasternSo- f lt(X) rn. lttft'rrilrt 2082 (SD).-AnrzoNr. C'hiricahua Mrs.. ncar nora; 260 700 m. Southward in western M6xico tcr C'cclarCulclr. Paradisc.53(X)ti. 2l Scp lt)07. Illuntr t710. Guerrero and Puebla. Baja California Sur, and central M6xico at least in Quer6taro.This is the only Sonoran Acat.vpHa NEOMEXTcANAMiill. Arg., Linnaea 34: l9(- 20). representativeof the tropical, mainly New World sub- I U65. Ricinot:arpus neomexicanr.r^r (Mtill. Arg.) genus Lir?o^rtachys(Klotzsch) Pax & K. Hof1m. This Kuntze,Revis. Gen. Pl. 2: 618. 189l .-TYPE: Unit- subgenus is characterized by p()ssessingonly l()ng- ed Stirtes,New Mexico. Wright 1817 & 1818 (syn- types pedicellatepistillate flowers in racemesor paniclesand G, not seen, isosyntypesNY!). According tcr (1995, subtendedby minute. nonaccrescentbracts. McVaugh p. lt37),Wright 1817at G was an- notated as the McVaugh ( I 96 I . p. l.l9 ) rreated Cory,theumulti.flrtra lectotype by G. L. Webster in 1964. Hclwever, it Standl. [: Acultplut ntulti.floru(Standl.) Radcl.-Sm.l appearsthat Webster's designation has not as a synonym of this species.but as p

Erect summer annual with deeply divided, glandu- Acabplu Iintlheinreri Miill. Arg.. Linnaea 3zl: ,17. 1865. Ricinot'ar- (Miill. lar-granular pistillate bracts; August-October. Thorn- pus lintlheimeri Arg.) Kuntze. Revis. Gen. Pl. 2: 618. 1891. TYPE: In the protologue Mtiller cites many \pecimen\. scrub, tropical deciduous forest, and lower oak wood- including Lintllteirner -520fiom Tcxas. At NY there is a specimen land in north-central, eastern, and southern Sonora; of Lindlu'imer520 |l that was labelcd as thc lectotypeby Lilian 75-940 m. EasternUnited Statesto Arizona, Baja Cal- Miller in I96'1.Since Mtiller almost surely did not see this spec- ifornia Sur. and much of mainland M6xico to central imen, it should not serve as lcctotype. According to Rogers (pcrs. America. McVaugh corum.. 1995).Lindheirner 520 at G, which Mtill- er cliclsee and studv. was labclcd as thc lcctotypc by G. L. Web Acaly"pha ostryifulia frequently has been referred to ster.also in 196.1.hut this lcct()typiUcati()nwas apparentlynever as A. caroliniana Elliot but this latter name is invalid publishcd. because Elliot was not describing a new species.In- AcolrJthu Iinrllttirneri Miill. Arg. vttr. trutjrtr Pax & K. Hoffln., in stead,he was misapplying the n'ameAculvpha coroli- Das Pll:rnzcnrcich IV. l-17. xvt IHc-fi tt5]: 25. 192.1. TYPE: niana Walter to plants of A. ostn'ifolia. L.nitcri Stutes. Arizona. f'hincahua Mts., Mrss Rhoda Riggs' Ranch. -5-5(X)11. -ll ()ct 19{16.Illunu,r !198 (Pirx lnd Hoffrnann Sonoran specimens fiom tropical deciduous forest did not indicatc in uhich lrerbariurnthey saw Illunu'r 119E. ll- and thornscrub lack gland-tipped hairs on the pistillate thc spccirrrcn$as at B. it has likcly bccn dcstroyccl.Therc is an bracts and herbage. while specimensfrom elsewhere i\otvl)c:rf ARIZ[#6()3011I1. in the state posses long. gland-tipped hairs. Both Herbaceousperennial with numerous stems arising morphs are present in southern Arizona, sometimesat tiom a central rootstock;July-November. Arrclyos and the same l

Mpio. San Carkrs: Bahia San Pedro. ltclg<'r l2l16. Mpio. Nar'

BenNnnore cTNEREAWiggins & Rollins, Contr. Dudley do not know the location of Scheele's original ma- Herb. 3: 213(-214); pl. 61, figs. 2 & 3. 1943.- terial, but there is a specimen of Lindheimer 523 at TYPE: M6xico, Sonora, [Mpio. Guaymas], l5 mi S US [#18149661!labeled as an isotype. of La Palma, basaltic h1ll, Wiggins & Rollins 227 Monoecious or dioecious shrub l(-3) (holotype DS[#2853471!). m tall; in So- nora flowering and f'ruiting March to October. Canyon Monoecious or dioecious shrub to 3 m; May-Sep- slopes at the ecotone of Chihuahuan desertscruband tember. Ecotone of Sonoran desertscrub and thorn- oak woodland in northeastern Sonora. where it is scrub, often on rhyolitic rock outcrops; I l0-600+ m. known for certain only from two localities but possibly Endemic to west-central Sclnora. more widespread; 800-1300 m. Also New Mexico, This speciesis distinctive becauseof the densevel- Texas. and adiacent northern M6xico. vety indumentum of mostly unbranched hairs on its Based on material fiom Durango, Marshall Johnstcln stems, leaves. and capsules. The leaves are usually (1980) described B. mvrit'ifolia var. incantsides.Fr>l- ovate but sometimes can be three-lobed on vigorous lowing his circumscription, our material belongs to growth. Although it was described and placed in Ber- var. mvricifitlia, but the distinction between these twcr nardia, it does not appear to belong in the genus and varieties has not been critically considered in our its affinities are not obvious- Our retention of it here work. is provisional.The axillary, long-pedicellatepistillate Webster (1993b, p. -5613)treated B. incana C. Y. flowers and the styles that are united most of their Morton as a syn()nym of B. nn'ricifttlia, but we dis- length and laciniate only at the apex are charucteristics agree.B(rnurtlitt int'ana is distinguished by its black- apparently otherwise unknown in Benrunlia. In addi- purple,thicker. glandulifbrnr stipules (vs. greento yel- tion. the leaves of this species lack the characteristic low or brownish. membran()usstipules): r,ery close, annular,crateriform glands fiequently presentin mem- short-rayedhairs on thc undersideso1'thc leaves(vs. bers of this genus. Also, the stamensand anthers are looser, long-rayed hairs): f'cvr,erstantens (-5-7 vs. I I black-purple (vs. yellow), and there is a united inner 20): and fess-dividedstyles. Yutskieyyclt82--16 (pro- whorl of stamens(vs. completely fiee stamens). visionally ref'erredhere below) is intermediatc in that the stamen number is of B. rnt'rici.foliu,but the styles Mpio. Ciulrynlrs: Sicrra l-ibrc. Microondas Avispus. vicinity of 2u"213'50"N.lll"0l'.l-l"W Irhis is thc t1'pclocality ()r vcry closc r() are less divided and the stipules are slightly black- rtl. I.'clg<'r ,3-5,91/,1, Sttitrrtttutrt 9(14: (luavrnas. 188-7.I'ulncr lO.l purple but ncrtt() the extant as is typical tn B. incana. (US). Mpio. Ca.jcrttc:Ii sidc of Prcsa Alr,uro ()breg

and relatively long staminate inflorescences. In B. yir- Herb. 23: 161ll. 1926. TYPE: M6xico. Jalisco. Barranca near idis the teeth of the leaves are larger and well-spaced, Guadalqara. Junc 1886, Palnrcr i,l1 (holotype GH!). and the staminate inflorescences are very congested. Mala mujer, ortiguilla. Winter-deciduous herba- The leaf pubescence of Sonoran material here referred ceous perennial from multiple tuberous roots and with to B. viridis varies from nearly glabrous to densely nasty stinging hairs on the herbage and inflorescences; pubescentwith short- or long-rayed hairs. Most spec- reproductive from shortly before the summer rains un- imens are sterile, and more flowering material will be til fall. Oak woodland. oak woodland-thornscrub eco- needed before this complex can be thctroughly re- tone, and tropical deciduous fbrest;310-1300 m. solved. North-central to southeasternSonora. Four subspecies were distinguished by Breckon Isla San Pedro Nolasco: E siclc ot islatrcl rrt hilhcr elcvations. /i<,1,gcr 961-l- llpi

nate, usually long-petiolateand with glands at the base Nlpio. 13lrrispc: SlrnllrRosrr ('linron nctrr Bar ispc. llTrilr,.5.1/. Mpio. of the blade, often palmately divided-dissectedwith .Alltrrrs: SicrriL tlc .Allttnor. Birrnrncir rlcl Salto. Ottrtrt I lO(t5. Mpi

l. [-eal nrarginstrxrthed: short livcd pert-nnialhcrb ... (-. rnartittitutu.t l' Leaf margins cntirc: hlrbit r,arious. 2. Dioccious: ri tlorvcrs irnctalous.

thc rays ol tllc stcllatc hairs relatitclv slout lrnd or,crlapping. "1. Stctns rlircrlcrrt. llrt brirrrclrcs sprcatling. thc pllrnt olicn irs widc as tirll or uitlcr: seeds.1.O .1.5 nrnt long . (.. cctlilitrnicu.s .1' Stcttts llt()sll\ ercct. thc bnrrchinr pattcnr strict. thc plant usually tallcr than uitic: scc.tls.1.-l 7.li rtrnr lont . ('. rll,g.qirr.rlr l' Mrtltoccious: rj llouers *itlt ucll tlcrclopctl ltctals (although sotnctirrrcstlecirluoLrs). 5. Stipulcs rcprc\cntcd bt corrspicrrorrr lonl stalkcrl !lands at son)e or rrost ol-lhc notlcr. 6. Aharill lctrl sLrrlacessparscll ltrrbcscentto glabratc (-. .sultjuttrurulus 6' Abariirl lelrl srrrlaccstlensclr, puhesccnt. 7. l-cirrcs lincar ]lnccolirtc: stylcs clch bilitl (stignras 6) . . . . ( . r'r,rrl.r,l.v.r 7' Lcares lltncc0late t() ()\'utc: styles cach -l or.1 tirrrcscliviclc-d {stiglrra: ll 0r nrorr) . . . . . (' t ilitttoqlttndtrlifi,r 5' Nodcs cghntlulrrr. thc stipLrles Iarior,rs but not stipitiltc glandular. l{. Stylcs cach I or .1 tirrrcs cliviclcd (stignras l2 or rrrorc). t). ShlLrb: ltbaxial surfltccs ot scpals stellatc pubcsccnt: ? scpals :lccrcsccnt irntl rrrorc than hrrll thc lcngth of thc rrraturc ll-uit: r' llowers itpctalous ('. uluntrtstuttts 9 Snrall trcc: abaxial surfrccs of scpals lepidote: ? scpals not irccrcsccnt antl lcss than half thc lcngth ol' thc lnature fruit: i llowcrs with pctals ('. utT. nrlt,as ll' Stylcs each hilid (stignras (r1. 10. Lcavcs nr()rc than 1.5 crrr wrdc. I l. Rays of thc stclltrtchurrs on the ovrry 0.2 0..1 rnrn lons: stylcs divrdetl l/-l 3/.1 thcir lcngth: locLrlesol tlre capsulcskceled...... ('. f lut t'.sct'rt.: I l' Rlrvs of the stellatehairs on thc ovary 0.7 2.2 rrrnrlong: stvlc'sdividctl r)carlvt() tlrc basc IoeLrlrsol thc capsrrlcs lounclcd . ( . tttuqdultttttt l0' Lcavcs lcssthan 2.5 crn widc. 12, Shrub: ? scplls glabrous or with f'cw scattcrcdhairs . ('.sttttoru( l2' Hcrbaceousor sufliutescentperennials: abarial surtacc of ? sepalsclcnsclt,pubcsccnt. lJ. l-cavcs lincar lanceolate(o narrowly lanceollrtc: ? scpals linclrr-oblong:\'()un9 ()\ irrv visiblc betwccn thc scpitls (. l,((ltttll,tttt.\ l3' Lcavcs tuostly lanceolateto oblonl to ()\'ate: ! scpals()\'atc. young olary covcrcti by thc scpals (.. p(rtt.\ii

CnoroN AI-AMosANLrslas alamosanrn] Rose, Contr. the southern margin

27"03'55"N, 108"56'W. Van Devender 9-l 1011. Mpio. Guaymas: (1981, p. 110) states that the seeds were likely of Sierra Libre, rd to Microondas Avisnas. Steinnnnn 578. Mexican origin. Grady Webster (pers.comm., 1995) has been unable to locate orieinal material. CRoroN cALrFoRNtcusMi.ill. Arg. in DC., Prodr. l5(2): 691. 1866. Oxydectes califomlca (Mtill. Arg.) ('rttrtn petticillalus las ltenitilkttuntl Vent., Choix Pl. 12. 1803. A Kuntze, Revis. Gen. Pl. 2: 611. 189I . Basedon Hen- nonren supcrfluum giving in synonymy thc earlier Cntton "cil- -.q " decandra procumbens Eschsch., M6m. Acad. Imp. i tttt t Iu nd uI i fi' r ur n. Sci. St. P6tersbourgHist. Acad. lO: 281. 1826; not Trucha, ortiga. Shrub I 1.5(-4) m tall; herbagebe- procumbens Cntton Jacq., 1760.-TYPE: United set with conspicuous stalked glands, the fiesh foliage States, (without collected in California specilic lo- sticky and smelling strongly of fiuit-punch; reproduc- cality) by Esch.scholtzin (holotype 1824 presumably tive more or less throughout the year. Frequently in at LE, not seen). disturbed areas in tropical deciduous forest, thorn- Hierba del pe.scatlo.Suffrutescent perennial, dioe- scrub, l()wer oak woodland, and the margin of Sonoran (e.9.. cious or, accrlrding t06: N of (iiiirocoha along thc rcl to Herbaceclus rlr suffrutescent perennial with narrow Clroquincahui.Sleittnutnn 6/-i: Siera tlc Alanros. N sitlc ol thc r-ange leaves;reproductive at various seasons.Oak and pine- ca. 2 km SW ot Alamos akrng thc trail tionr El Chalat

sli (Klotzsch) Kuntze, Revis. Gen. Pl. 2: 612. Rio Mayo, 9 Dec 1939, Drouet & Richards 3923 1891.-TYPE: M6xico, Chihuahua, near the city of (holotype A, not seen; isotype DS[#273545]l). Chihuahua, Potts s.n. (holotype BM[#801U7]!). Small shrub resembling Croton sonorae in habit but (..ntton tttrytnbalo,rls Engelnt. in Rothr.. Rep. Ll.S. Geogr. Surv.. readily distinguished by the multifid styles and large, Wheclcr 6: 242( 243). 1878. TYPE: llnited Statcs.Arizona. conspicuous stipitate glands on the herbage, inflores- Cochise Co.. Canrp Bowie in Apache Pass.('hiricahua Mts.. 50(X) cences, and flowers; flowering recorded in December fi. July ltl74. Rotltrrx'k -506tlectotype I,I()J#llO.15ttll. here cles and February (C. sonorcte flowers during the summer rgnated).Fivc collections were citcd in thc protologue. none ol' which has bccn preliously dcsignrrtctllectorrpc. rainy season).Endemic to Sonora, ca. 5 50 m, and (.r(,t(,n(rernoplllll.r Wooton & Standl.. ('ontr. L'.S. Natl. Ilertr. l(r: known to us fiom only three collections, all from 1.14(145). l9l-1. TYPE,:Iinitcd States.Nc* Mcrico. [)og Mts.. coastal plains where the deep, alluvial soil supports a Dog Spring. l6 Scp lll9.l. lvlt,ttrtts l-l-j6 (holotypc densely vegetatedcoastal thornscrubor thornscrublike uS[#23,116]lr) mesquite-d()minatedvegetation within Sonoran des- Perennial herb: August Noventber. Northeastern ertscrub. Much of this habitat has been converted to Sonorain grasslandand ()akw()()dland; l2-50-l-500 nt. agriculture. Texas to Arizona. s()uthwardto San Luis P

\1pio. llLrlrtrrbrrrlpo: Llachocr). affoy() I krn NIi of town, 16.,1,1'N. CnoroN soNORAuTbrr., Botany of the Boundary. lin 109 ll \\'. 17 I)ce 198(r.Mttrrirt.Q O'Rtturk,.r.r. Mpio. Hcrnxrsillo: Emory. Rep.U.S. Mex. Bound.2,pt. ll: l9-1.ltt-5t3. ta. 5 rtti \ ol I)Lrnta Blrjrr at clr. 1.5 rrri inland (belwccn Tasti()ta ilncl Oxydectes sonoroe (Torr.) Kuntze, Revis. Gen. Pl. 13alrirrKirrirr. errlrstlrlIrlrrirr. shrrtlc ol rrrcsquitc,Iiel,qrr 12619. 2: 613. 189l.-TYPE: M6xico, Sonora,IMpio. Gen. Plutarco Elfas Callesl. Sierra de Nariz, July 1t355. Cnoto: rt:\r,\srs (Kkrtzsch)Miill. Arg. in DC., Prodr. Schott.r.r. (hol()typeNYI). f 5(f l: 691. 1866.Hende(undre texensisKkrtzsch in Wiegnrann.Arch. Naturgesch.1: 252(-253). 184l. ( rriltttt prittglti S. \\'rrlsorr.Proc. Arrrer.:\cad. Arts 20: 37-l( .17-l). O.rydecte.sle.\ensis (Klotzsch) Kuntze, Revis. Gen. - 'IYPH: 1885. Meirico.n()rtlt\\rstcrn Sonolt. IperhapsMpio. Pi- Pl. 2: 613. 189l. TYPE: United States,Texas, ticluitol.low rangc ol'hills lbLrLrtl{) nri lhrrrrthc colst. August (The 1881. I'rin.glt .f./r.(h()l()typc (;H I). Itl35. Drrorrnrottd specimenseen by Klotzsch ('rrttrtt qottlulalli Circcnnr..Pnrc. Arrrcr.r\clrd. Arts 19: tl L 1901. was presumably at B and is likely destroyed. A TYPE: Mfrico. Oax:rcu.C'uicatkin. (r(X) nr. l6 Scp 11399.(ior- probable isotype. Drutrtntottd256, is at GH Lll ). :.ilt-- 9ti1 (liolotvpc (iH. not sccn: isotypc MtsXtll#511.1 l7l!). ('r(,ton utt(truulil.i M. E. Joncs. C'ontr. W. tsot. lu: .17( -18). 1933. ljor svnortvrrt\ sce Jolutstort 1959: l()6. TYPII: M6xico, l-owcr Calilirrlia C'alifirrnir Surl. l-oreto. ll]aja Tortolita. Erect to ascendingdioecious annual, ofien Cayuca Ranch. 2-l ()ct I930. ./ont,.r 275O() (holotypc POM [#le]n53ll) very leafy and sometimesreaching m()rethan I m tall; February October. Thornscrub, grassland, and oak Small shrub, the leaves v.rrying greatly in size de- woodland in nclrth-central and northeast to east-central pending upon soil moisture and turning orange as they Sonora: 150-1350 m. Also Chihuahua and the south- age and fall; flowering mostly during the summer rainy western and midwestern United States fiom Arizona. season;July-October. Sonoran desertscruband th()rn- New Mexic(). and Texas to South Dakota. scrub; near sea level to 800 m. Southern Arizona In many respects similar tct C. culifornicu^sand dis- through western and central Sonora to Sinaloa and tinguished by the annual, less-branchedhabit. Also, Baja Califbrnia Sur; and disjunct in Guerrero, Puebla, the hairs on C. te,yensl.stend to be less dense with the and Oaxaca. rays more slender. Their distributions are allopatric.

Mpio. Guaymas: Canrin del Nacapulc, Fclger 85 ,36/. Mpio. Santa Mpio. Bacoachi: Sien'a de los Ajos. 1.1.0nri by rd N of Bacoachi. Ana: hills bet$,i'enMagdalena and SantaAna. 7 nri S of Magdalcna, 3(f.19'N, 109"5.1'W L'ishbein 1277. Mpio. Nogales: 7 9 mi S of Wiggins 719-1.Mpio. Puerto Penasco:ll.3 rni by rd S of Sonoyta. Nogales along MEX 15. Gentry /9-i-52.Mpio. Benjamin Hill: near granitic mountain, L'elger 16728. Mpio. Huatabampo:Los Cerillos. Rancho Polvadera.W of Noria. Shreye6015. Mpio. Soyopa: Rfo S of Nirvojoa. Gentn' l4-191. Yaqui. across ll'onr Tonichi. l'oolin 277.

CnoroN SUBJUNCUNDUSCroizat, Bull. Torr. Bot. Club CnoroN wrccrNslr L. C. Wheeler, Contr. Gray Herb. 69: 451(-452,457). 1942.-TYPE: M6xico, Sono- 124: 31(-38). 1939. Based on Croton arenicola ra, [Mpio. Navojoa], Navojoa, in thickets by rd near Rose & Standl.. Contr. U.S. Natl. Herb. 16: 12. a/ Steinmann and Felger ALISO

l9l2; not Croton arenicola Small, 1905.-TYPE: nate flowers on articulated pedicels; sepals 4-6; petals M6xico, Sonora, [Mpio. Puerto Pefrasco], Adair 0; stamens mostly 9-30, filaments very short and con- Bay, sandhills, 20 Nov 1908, Sykes 62 (holotype nate into a stiff column. Pistillate flowers usually with us[#s]426])t). a 5-l2-parted pinnatifid and often gland-tipped calyx that enclosesthe fruits; petals 0; ovary usually 3-1oc- Dioecious shrub or subshrub l-2.5 m tall with strict ular, with I ovule per locule; styles united into a col- or sharply ascending straight branches; variously re- umn and often with an expanded peltate stigma. Fruits productive nearly any time of the year. The Gran Des- capsular. Seeds ecarunculate. ierto in northwestern Sonora on low and stabilized to A pantropical genus of about I l0 species,the ma- high and shifting dunes and sometimes on sand flats; jority of these New World with the center of diversity also along the international border in adjacent Yuma in Brazil. Six speciesin M6xico. Ref-erences:Webster County, Arizona, and the Algodones Dunes in south- and Armbruster 199l. Webster and Webster 1972. eastern California. Endemic to the Lower Coloradcr Valley of the Sonoran Deseft. DaI-ecHl\4prAScANDENS L., Sp. Pl. 1054. 1753. var. Croton wigginsii is a segregate clf C. californicus, scANDENs.TYPE: According to Gillespie(1993, p. and relationships between these and amclng other 76) and Webster and Armbruster (199I, p. 160), members of the C. dioit'u.sCav. complex are unresolv- tiom the West Indies,plate l0l in Plumier,Pl. Amer. ed. In C. wigginsiithere is an unusuallylarge range in fasc.-5. l7-57. seed size; the larger seeds are fiom large-leaved,ro- bust plants, whereas the smaller seedsare fiom rela- Fol synonvnrrscc \*chstcr rrntlArrrhnrslcr l()91.pp. l6O l6l. tively stunted. drought-stressed plants (see Felger perennial vine or scandentshrub (in 1980,pp. l0-5-106). Robust the Guaymas region sometimesa facultative,nonvining Mpio. Sun l-uis R. ('.: 15..1nri E ol San l-uis on MEX I. lt hordc'r annual) with 3-lobed leaves:reproductive at various rttarkcrl9ll. graniticltills. /r,1qr,r'lt'rZ(/l:hir:h shittingtluncs -l knr seasonsbut rnostly in responset() sumrner rains. Trop- N of Sicrra rlcl Rosario. l'tlttr 75 -io. ical deciduousfirrest of southeasternSonora and in the Guaymasregion (Sierrael Aguaje) and the SierraBav- yrr('()RrrNsrs CnoroN V. W. Steinm. & Felger,Novon 8: iso in riparian canyons surroundedby Sonoran desert- in press. scrub; l5 750 m. South to subtropicalSouth America. Subshrub (but flowering in first season)to ca. I m Wiggins (196,1,p. tt00) refers the Sonoran plants to tall, with linear-lanceolateleaves and stipules repre- var..fimbriotc (H. B. K.) Miill. Arg., but according to sentedby stalked glands; reproductive in the spring as Websterand Armbruster (199I, p. 16l ) thi\ is a syn- well as during the summer/tall. So f'ar known only onym of vlv. ,;<'anden^s.The three other varietiesof D. from a small area of east-central Sonora in oak and scctndensrecognized by Webster and Armbruster are pine-oak woodland; 1250 1700 m. It is very common restrictedto South Amerrca. in the vicinity of Y6cora and expectedin adjacentChi- Mpio. Cuaynurs: Ciririin rlcl NacapLrlc. / r'1,qrr.,\-5-tJt: Sicrra cl huahua. Aguirje. Las Barajitas. l"tlqtr t).5 /,Y.i,.l:('antin la Prntada. Vutt I)L trnder & Vutt I)etuultr,YJ -l-i. N{pio. Alarrros: Sicrra dc Alanros. .1 Mpio. Sahuaripa:2 knr SE of airfielcl.ca. knr SSW of Mulatos. Sttirtrrtttrtrt9-l -l 1). 28"37'.19.| "N. I 0ft':15'38 .2"\N. I.e I,qc r & B il rq ue: 91_5 74. Mpio. Yrr cora: 7 nri W o1'Yicora. Gttldlpr,g 76 18-l Ranclro[,a Pinosa. lO.I kni W of Maycoba on MEX 16 untl ca. 1.5 km N of hwy, DALEMBERTIA Ba1ll. 28'2.1''16.6"N,I08"i13'13.7"W l"?Iscr t)-12.17, 91-.1.1 I. Shrubs, sometimes herbaceous;monoecious. Latex milky. Pubescencesimple or lacking. Leaves alternate, DALECHAMPIA L. long-petiolate,entire to toothed or lobed, palmiveined. Vines or lianas, rarely subshrubs to shrubs, some- lnflorescencesbisexual, spicate,with a f'ew I flowers times with urticating hairs; monoecious.Latex absent. at the base and numerous d flowers above. Staminate Pubescencesimple or nearly absent, sometimes urti- flowers short-pedicellate,consisting of a single stamen cating. Leaves alternate, simple and ofien lobed (ours) enwrapped by a solitary sepal. Pistillate flowers ped- or compound, palmi- or penniveined. Inflorescence icellate, with 3 imbricate, basally biglandular sepals; pseudanthial, usually borne on an axillary branch con- petals 0; ovary 3-locular, with I ovule per locule; sisting of 2 large, subopposite, often colorful bracts; styles entire, connate at the base into a column. Fruit d portion usually a pedunculate pleiochasium of 5-7 capsular. Seeds ecarunculate. sessile l-3 flowered cymes and a resiniferous gland, A Mexican and Central American genus of about the whole being surrounded by an involucre of 4 five species. Reference: Pax and Hoffmann 1912. bracts; I portion a subsessile(l-)3-flowered cyme sit- uated abaxially at the base of the d peduncle. Stami- Dar-ElasEnrrA popuLIFoLIA Baill., 6tude Euphorb. VOLUME 16.NUMBER I Euphorbiaceae of Sonora 25

(545-)546:pl. Y lig. l1-15. 1858.-TYPE: M6xi- tack-shaped glandsl plant (except the ovaries) lacking co, Oaxaca,Tehuantepec, Andrieux 107 (holotypeP, malpighiaceous hairs . . D. adenophora 3' Leaf margins, stipules, and ? sepals eglandular: plants not seen;isotype G, not seen,photo [Field Mus. neg. '72O7lt). usually with many malpighiaceoushairs. .1. Plants herbaceousi stents mostly ascending to spread- ing or sometimcs thc main axis at first crect but the Ak ot eriu pringlei Fernald. Proc. Amer. Acad. Arts 36: -193.190l. branches spreading and seldom straightl d petals fiee TYPE: M6xico, Guerero, limestone mountains above Iguala, 26 fronr the staminal column. appearingto arisebetween Sep 1900. Pringle r9.l-l-l(lectotype GH!. here designated.t.There and altcrnatingwith the glands: styles branchesterete arc two sheetsof this collcction at CiH. Thc flrst has tl'uits.whrle at the apex. thc sccondhas both fiuits anclflowcrs. Fcrnalrlcarcfully tlcscribed 5. l-cavcs mostlv ()vate-elliptic,the apex (at least on floral traits in the protologuc. s() wc dcsignatcthc sccond sheet the rnajoritl,of leaves)pointed: adaxial surfaceof as lcctotypc. thc youn-ulcaves with hairs unitirrrn in thickness . I). netnnext<'uttu Drought-deciduousshrub to ca. 3 m tall; reproduc- -5' Lcavcs nrostl) ob()vatet() spntlllatc,thc apcx nrost- tive during the summer rainy season.Known in Sonora lv broadlv obtr.rrcto tnlnciltc (pointcd on plants only from the southeasternpart of the state in shaded l.nrrrr Isla Sln Esteban): abaxial surface of the ouns lear cs with sonrt-hairs usually thinncr than canyon habitat of tropical deciduous forest in the vi- r ()thcrs I). .st'rrulu YLtf. .\r rratu cinities of Gtiirocoba and Santa Biirbara:-550 1000 m. J' I)larrlssLrbshrrrhhr': stcnrs nr()stl\,crcct and straight; d Sonora tcl Oaxaca and Puebla. pctlrl\ unilc(l t() thc strrnrinrlc()lunrn 1llbasc. nppcanng Wiggins ( l96.1,p. t3l0) initially reportedthis species 1() rrri\c irhore thc glands: style branches sornetirnes for Son

Mpio. Navoloa:4 tni E of Navojoa. (jcntr.t 17-5(t.Mpio. Grrarrrras: Mpio. Alanros: N tif Alarnos. ncar Agua Claliente.rocky outcropping 2 tni NE ol' San Carlos. lVir;.qil,r& Rollin.s /,9-1.Mpio. Pitrqtrito: in lixrthills. Gcntn 1811. Trcs Mirrias lintestoncquarr.y. ca. 2ll krn vicinity of Rancho Arivaipa. ca.8 nri ENE of Pozo ('oyotc. cu. t'. of MEX l5 in Navojoa. 27'06':16"N. 109'I)9'.15"W.Van l)et,entler 29"37'N. I I2"17'W. l.al,qer |782-i. Mpio. Caborca: C'aborcu.lirnc 95, I 10-1. stonchills.25 Aug l8li-1.Prur,q1r,.s.ri. (P()M). Drr,qxrsLANcrEor.ArA (Benth.) Pax & K. Hof-fm.,in Das (Millsp.; Dlraxrs BRANr)F.Grrrar Rose & Standl. var. tN- PflanzenreichIV. 147. vr [Hefi 5]l:11. 1912.Sero- roNSA I. M. Johnst., Pnrc. Calif. Acad. Sci. ser. IV. phvton lanc'eol.atumBenth., Bot. Vluta(Benth.) Engelm. inton,sa(I. M. Johnst.)J. W. Ingram in L. D. Benson & A. Gray. Pl. Lindheim. 25. 1845. Argvttutmnia & Darrow, Trees and shrubs

Shrub 1-2 m tall with weak, openly spreading Dtrnxts MANZANTLT-oANA(Rose) Pax & K. Hoffm., in branches; September-November, so fer as known. Das Pflanzenreich IY. 147. vr [Heft 57]: 59. 1912. VOLUME I6. NLIMBER I Euphorbiaceae of Sonora 21

Arg-,-thamnid monzanillodlld Rose, Contr. U.S. Natl. species). Interestingly, both Arg,vthamnia gracilis and Herb. 1: 357. 1895.-TYPE: M6xico. Colima, Man- Ditads grac'ilis, here treated as synonyms of D. neo- zanilfo, l-31 Dec 1890. Polmer 1073 (holotype ntexicunu, are independently based on sepuratecollec- us[#208e241!). tions of the same phenotypic variant with relatively lon- ger pistillate sepals and large (5-_8cm long), subgla- Argttlntnnia gentr.\'iL W. Ingram. Bull. Torr. Bot. C'lub flO: .1ll brate to sparsely pubescent leaves. Such plants appear (J22). l9-53.l)iruti.s .qentrti (J. W. Ingrarn)Radcl.-Srn. & R. 'I'YI)E: Govacns. Kew. Bull. 52: 191- 1997. Nleixico.Sinalou. to be nothing more than robust individuals growing un- Ccrro Teconrate.W o1'Pericos.l(X) Il. l9 Fch l9-1O.Ottttrt-5761 der highly tavorable conditions during the summer (b()lotvpcLJC[#65 I 767JI). rainy season.The variation in both leaf size and pistil- Suffrutescent perennial or suhshrub with straight, late sepal length is continuous.In addition to the type erect to ascendingbranches. distinctive in possessing ctf Dittrxi.s grucili^s,we have only seen a f-ew Sonoran conspicuouslyreticulate-ridged seeds and stylesunited specimens of this variant, e.9.. Gentn- 47 17, Gentry below into ercolumn. Rocky ureas in the trclpical de- 4815. Vtut Devender 9-l 87 l. ciduous filrest of s()utheasternSonora: 2zl0 -5(X)m. ()axaca, \'lpio. ISrrrispc: 7 nri E ot Cokrnia Morekrs, rd to Colonia South along the Pacific sl()peto C)axaca- \\'ltirt, 11),\ (RS'\). i\Jpio. Prrcrlo Pcnasco: rockl' rrre-saS of Pinacatc Argvthomnio ,qentrti is here treated as a synonynl ['clrk. /"r,/qlr 7c.1.1;.sMpio. Ciulrvrnas: ('anirn tlcl Nacapule. /'i'1.q,cr of D. manzurtilloutttt.In the pnrtologue. Ingraln distin- ,S-rli6: (iLunrrras. basrltic shatle skrpcs on hrushv hills. (jrnln (iclln.l,S-l-5: guished it fiorn D. nurrt:.turilltxtttuon the basis ot' sta- JZl1. \11rio. ..\lrrrrros: N ol Alarttos. near Tcpistiltc. llio (iLurlrurir bclsecrt [-a Jutrta alrcl Citriqarhy. Sl<'irtrrtttrtrt9-] 115a. petals stemswith mal- mens included within the ancl \l1riir. Ilurtrrhrirril)(): Iluatahilrnpito. 9 Mar l9il13. Murtirt .s.rt.l''I.pit't. pighiaceoushairs. but thesecharacteristics arc not well \rrrrrirlr: Icrir'lrirc rlc \litsiltea. r\ttot'tt Masiact Vttn I)t'r'cndcr 9-l marked and. in ()ur ()pini()n.within the range of vari ation crf D. ntan:pnill.rsanu. Drrrrts st:RR..\rr(lirrr.) A. Heller.Cat. N. Amer. Pl. Mpio. Alanros: NW ot Alamos. ('crro Vcrtlc, ort rci hcttrcctt I.os ?rrrqucs and PieclrasVertlcs. ./rllil.r 9O 252 Arrovo (iocltico. I I 5. lli9tt. \'lrr. \r,tiR.\'r..r.Aphrtra .rerroto Tcrrr.,Botany kni by air E ol San Be-rnattkr.27'21'-15"N. lOlS'+-l'.lO"W. Sttirttnrurrt o1'theBounclary'. Iin E,mory,Rep. U.S. Mex. Bound. 9-l 6(/: Ciiirrocobacnrssing of Rfo C'uchrr.iuclui.12..1 knr h1 lrir SSIi 2. p1. ll: l9'7. ltt58. Ar,qr/humniaserrato (Tbrr.) ol Alatrros.17"5(r'15"N. lO8'5 1'W. I'att l)trurdtr 92 521- N{rill.Arg.. Linnaea3.1: 1,17. 1u65. TYPE: United States.C'alitirrnia Ithe label gives Sonora], sandy \t,()\rt,\r(..\\A(Miill. Arg.) A. Heller.Cat. N. Dtl.rrts plain\ near Fort Yurna, Jan l8-55, Schott ^r.rt.(lec- An'rer.Pl. 5. lt3c.)u.Ar,qvrhturtrtiu rteontexictnrrr Mi,ill. tot)'pc NYI ex herh. T

Nonseasonal annual to short-lived herbaceouspe- Robust n()nseasonalannual to short-lived herba- rennial. Widespread and common in Sonoran desert- ceous perennial with a well-developedtap root. Lower scrub, thornscrub, and tropical deciduous forest Colorado Desert in Sonoran desertscrubon sandy soils throughout much of lowland Sonora fiom near the Sin- including klwer dunes and occasionally on rocky aloa border to the Pinacate region, and also in grass- slopes adjacent to sandy habitats; generally replacing land in northeastern Sonora; near sea level to ca. 900 D. nectmexiceno on sandy soils. Northwestern Sonora m. Southern Nevada, California to Texas, and Baja southward to the vicinity of El Desemboque Rfo de la California (both states), to Coahuila, Sinaloa, and Du- Concepci6n, and lsla San Esteban; near sea level to rango. 225 m. Also southwestern Arizona. southeastern Cal- This species is closely allied to and perhaps not al- ifornia, and both states of Baja California. ways separable from D. seftata (see note under that Ditaris sendta and D. neomexicand are very simi- 28 Steinmann and Felger ALISO lar, and the boundaries between the two can be indis- where in the region. Otherwise known from south- tinct. Ditaxis serrata is usually distinguishable from eastern California and reported by Wiggins (1980, p. D. neomexicana by its more robust growth habit, 119) for the east flanks of the Sierra Judrez in north- stouter and deeper tap root, usually obovate to spatu- eastern Baja California. Endemic to the Lower Colo- late leaves that are broadly obtuse to truncate at the rado Desert in Sonoran desertscrub. apex, denser indumentum consisting of hairs of vary- Mpio. Puerto Penasco:Puerto Peflasco.Casa (ca. ing thickness, and differences in the seed surfaces; the Garcia 3 krn E of ccntcr of town), 50 ft. lU Mar 1980. Yarskla'r'& 8O1-1. seeds of D. neomexicana usually have deeper, more conspicuousdepressions, the sides of which bear fine DRYPETES Yahl but conspicuousradiating lines. Leaves of D. serrata, which are broadly obtuse to truncate, are rarely like Trees or shrubsl mostly dioecious. Latex absent. those of D. neomericana. ln a similar f'ashion.some Glabrous or pubescentwith unbranchedhairs. Leaves leavesof D. neomexicana-although usuallyjust a few alternate, ofien coriaceous and asymmetrical at the on an unusual individual-can have broadly obtuse base,entire to serrate,penniveined. Inflorescences uni- leaves,but in our experience,these are not truncateto sexual,axillary, f'asciculate.Staminate flowers with 4 the extent that is common in D. serrctta. The local -5 sepals;petals 0; stamens 3 to many, filaments fiee. distributions of these species in northwestern Sonora Pistillate flowers with 4 5 sepals; ovary l-4-locular, are narrowly separatedby the difterences in habitat. with 2 ovules per locule; styles short to absent,stigma and in places of contact, such as the alluvium

l. Lcavcs nranifestly serratc. E. r.rstipulutu ' f Lcavcs cntire (rarcly with one or a fcw scattcred.irrct:rnspicuous tccth in Ii. criuntlru). 2. Shrubs. 3. Stents succulcnt.straight, spinescent tippecl, lealless or with lcaves li'w. sessilc,antl lcss than I crrr long suhcyathialleaves filifilr-nr: seeds carunculatc Ii. cenxtermo l' Stctrts wootly or semi-sttccttlcltt. not spincsccnt. scasonally lcaty, thc lcavcs irt least I crn long anti pctiolatc: suhcyathial lcrrvcs r,ariously shapctl but not lilitirrrn; sccds ccilnlnculiltc. -1. Stcnr lcil\'cs ternittc. 5. Appcntlagcs shortcr thtrn thc involrrcrc.lcss than 2 nrnr long. not tinged with pink I:. crtlletioide.s 5' Appcnclalcs longcr thlrn thc involucre. rrrorethan 2 rrrn long. olien brcoming pink-tingcd with age . ..E..wtnti tl. Stcrn lcilves llltcrnatc. 6. Hcrbage. involrrcrcs.ovaries. antl capsulespubescent . E. tttisertt 6' Hcrbage. involrrcrcs.ovaries. and capsulcsglabrous. 7. Petioles cqualing or longcr than thc bladcs: lcaf'bladcs obovate to broadly ovutc. thc apcx obluse t() enrarginatc; appendages grccn t() yellowish grccn. I mnr or lcss in length Ii. culi.litrnicu 7' Pctiolcs mostly shorter than thc bladcsl leaf bladcs linear, lanceolate, t() narr()wly ovirte, thc xpcx acute: append- ages whitc, morc than I nrrr long . . I.). gentrvi 2'Herbs. 8. Appcndages arching ovcr and concealingthc glantls; styles not dividcd: capsulcs noticcably longer than broad: carunclc consprcuous.nearly as broad as thc sccd Fl. eriurtthu ti' Appendagcs not concelling thc -glands:stylcs divided or n()t: capsulesas broad as or brcader than long; sccds lacking a carunclc or the carunclc relativcly inconspicuousand not nearly as broad as the seed. 9. Appcndagesbi- ()r tripartite or palrnatelyor linrbriately parted t() the base. 10. Leavcsofthcprinrarybranchesprcdorninantlyoppositc,usuallylincar;appcndagcsbipartedlseeclslackingdeeppits E. bilobattt l0' Leaves ol'thc prirnary branchcs predominantly alternate,ovate to lanccolatc to orbicular; appendages3 or morc partedl seedswith scveral rows ol' deep pits. the bottoms of which fiequently contain a minutc. sharply punctifbrm pir. I l. Stipulcs conspicuous.subulatc: styles not dividcd E. sonorue I l' Stipules inconspicuous,glandulifbrm; styles divided. 12. Petioles attached subpeltatelyabove the basel cyathia ananged in nronochasialcymes; subcyathial leaves linear-filifbrm, very difl'erent in shapc fiom the vegetative leaves E. dioxoreoldes ssp. attenuatd l2' Pctiolesnot peltate,attached at the baseof the blade: cyathia arrangedin dichasialcymes; subcyathialleaves generally orbicular to ovate, resembling the vegetative leaves only smaller in size. 13. Involucre, glands. and appendagesgreen; glands 5: divisions ofthe appendages3( 4), Iinear.tingerlike E. tn.tmrtiJett 13' Involucre. glands. and appendages usually suflused with red-purplel glands 4; divisions of the append- ages 3-6, filiform, threadlike E. subreniformis 9' Appendages not divided, at most broadly and shallowly lobed. 14. Leaves linear; glands 5. Steinrnannand Felger ALISO

15. ()r'aries pubescent .... E.sphaerorlti:.a l5' Ovarres glabrous. 16. Anntrall appendagesovate to triangulitr.p()rtion extcndin,l beyond the gl:rnd 0.8-1.-5nrm long .. ' l. ltr'tttt,'tt,'i,lr's l6' Perennialhcrb: appenclagesIincar to naffowl\'()vate. porti()n extendrng bevond the glancl 1.7 2.9 ntm lon-u 6. sp. I l-cavcs efliptic. lanccolate.ovate. ()r oblong (r'arcly lincar in unusual rnorphs of I:. uruntirtt'tt.but then thc glands 2 J)i glands( | )l -5. l7- Pcrcnnialfi'otnanttntlctgroundtuher:lcavcsopposite.thoscirtthcbascofthe'"inflorcscencc"soltrctilnesternatc I',. tttut ntptt,s l7' AnttLrals:caulinc lcavcs altcrnatc but the floral lcavcs oftcn oppositc. lll. Hcrbagc ttlanilulrr' pikrsc: altpcnduges usuallv grccn. I'.. ltutrtuyen.si.s l1{ Het-bage ltot gl:rnrlrrlirr:appcndalc-s white to purprc. 19. (ilantls rttostlr I -1.olicrr tingcclrrith prrrplc: sct'rlsuith severalrows of'dcep pits

. . . . 1.. \ttutntlt rt \itf. q/1/rill//itl l()' (ilittttls 5. not tingcd uith pLrrplc: scccls lacking dccp pits I:.sinulru'nsis

Ettpnot

The appendasesvary from small. green, and incon- Mlri

F,Ltltltrtrbittrt,r'lrr Klotzsch irr Sccrn.. B()t. Vov. tlcrirld 177. ll{-5(r. TYPF.: Mttxico. Sicrrr Matlrc. on tlrc rtl l.nrrrrDur:urgo to IL'1ric. Et I,uoHtrr\r,rr.\\'r'rr.\ Benth.. Br,tr'rr lirrtr S. \\ltson. Proc. Anrcr. Acatl. Arts llt: l-50. I'.trltltrrrltittltlirrtrttSrvVirlson. I)rot.Arrrcr.Acirrl.Arts2l:-l-ltl( +-19). lSt l I \ [,]:: \lcirieo. ('oltlrrriltr.12 27 lcagucs SW ot' Pan-as, lSfi(r..111r'rrtrr l,li,.tt.t tS. \\'ttl\()n)\1illsp.. Fit-ld Mus. Nat. Hist.. Srrn | .rr enzo tlt l li.srulr.\ltrr I llE0. I'ulrnrr l2 l,\ (holotypc GH !). Iirt. ser.l: -117.191(r. [ \'PF.:NIrtrico. \()Lttl)wcstcrn ('hihrrlrhLrlr. HrrcicntlaSan N'ligLrclnclr I3ltopilus.Scp lltlt5. Puln<'r l8l (lcc Nonseasonalannual or sometimesshort-lived peren- totypc Gll!. hcre clcsisnatctl). nial hcrb. thc leaves linear.the lower ones Iiultfutrbiu pudilitliu Brantlegcc. I rnir C'llil. I)ubl. Ilot. (r: 5-1. alternate. l9l.+. TYPE: Mi'xico, Oaxaca.Srrn (lcrotrinro. irccording lo tlrc the upper ()r)esf()rnring wh()rls heneaththe cyathia. prot()loguc, "dry rocky plarns. Pichacho San (icroninro." ()ct Sonorandesertscrub and thornscrubin westernSonora: 1913. PLtrpusr)9.5(, (holotypc tJ(-l# l7l0l-1ll ). near seil level to cu. 137.5rn. Ila.ia flalifirrnia Sur tcl southeasternClalifornia. eastward to southwesternTex- Candelillo, Jumete. Shrub 1.5 4 m tall with weak. as, and southward to Coahuila and Durang(). wandlike, terete stems.and quickly drought-deciduous ternate leaves.usually reproductivewhen leafless.Oc- Mpro. PLrcrloPcnrrsco: Sicrra Pinacatc. I"tlger /9.1.5.1.\{pio. Hcr tober-May. Sonrlran desertscrub.thornscrub, tropical rnosillo: -5rli b)'rtl E ot Bahia Kino. 1:e1,gcr9(/5.5. N{pio. Ciuayrnas: deciduoustirrest. and rarely in oak-pine woodland; 25- strln(l at E:tr-roSoklitckr- Fel.qcr,\1-10(t. Mpio. Hrurtlrhalllx):Estero l30O m. North-central Sonora tcl Central America. Sirrrtrr[Jrirhrrr:r..] knr W of Huatablrrrr.rito.26l)cc lt)86. l\4urtitt & ( ) Rottrk<,.s.n. This species is very similar to the West Indian E. cymosu Poir. 1: E. nudi.florctJacq.), and possibly the ErrprroRnre EXSTIpIit.ATA Engelm. in Torr.. Botany of two should be considered conspecific. The only dif- the Boundary, lin Emory, Rep. U.S. Mex. Bound. ference appearsto be a tendency for looser "inflores- 2, pt. lf: 189. 1858. Chamaesyceex.stipulato (En- cences" and slightly smaller cyathia in the West Indian gelm.) Rydb., Bull. Torr. Bot. Club 40: 54. 1913. plants. The sap of E. colletioides is reportedly very Zvgophr"Ilidiunt exstipttlatum (P,ngelm.) Wooton & poisonous, with as little as one drop said to produce Standl.. Contr. U.S. Natl. Herb. l6: 146. 1913.- serious diarrhea (Joltal 2I l3 and from local guide in TYPE: United States, "Novo-Mexicanae," gravelly Alamos). banks of the Rio de Norte near Santa Fe. 24 May Mpio. Carb6: microondas 5 mi N of E,l Oasis and 47 mi N of Her- 1841, Fendler 790 (lectotype MO[# I 9 I I 306] !, des- mosillo, Phillip.s 75 l-11. Mpio. Curnpas: l6 mi by rd E of Mocte- ignated by Wolf 1988. p. 1626). zuma. Hastings & T'urner 65-100. Mpio. Guaymas: Sierra Libre. rd to Microondas Avispas, near summit. Fel,qer 85-828. Mpio. Y6cora: Euphorbia alicette A. Nelson. Bot. Gaz. :{2: -50. 1906.-TYPE: Unit- Y6cora hwy 2.6 mi W of old Y6cora turn-off. 28'21'N. 109'03- ed States.Wyoming. Hanville. l5 July 1894. Nel.son549 (holo- O1'W, Jot'al 2,/1-i (ASU). Mpio. Alamos: Alamos. Gentry 2920. type RM[#,1856]l). -)z Steinmann and Felger ALISO

Euphorbia ex.stipulataEngelm. var. lata Warnock & M. C. Johnst., Euphorbia t'olimae Rose. Contr. U.S. Natl. Herb. l: 356. 1895. Er- SouthW. Naturalist. 11: 121(-128). 1969. TYPE: United States. mecanthus t'olimae (Rosc) Millsp., Field Mus. Nat. Hist.. Bot. Texas, Brewster Co., Big Bend National Park, W side of Chisos ser. 2: ,114. 1916.-TYPE: M6xico. Colima. 9 Jan-6 Feb 1891. Mts.. Ward Spring,.1000 ft. 18 Aug 1955. Warnock l-1104 (ho- Pulnter I 170 (holotype US[#2089331!). lotype SRSC!). Euphorbia longipetiolutu M. E. Jones, Contr. W. Bot. l8: 55. 1933. TYPE: This was basedon two collections: "No. 2'7511a. Summer-fall annual, noteworthy among our species la Barranca.Guadalajara. Jalisco. Nov. l2 1930 and same loc. of subgenus Agaloma by possessing seffate-dentate No. 27538." At POM we have been able to locate only .lones leaves; northeastern Sonora, ca. 1700 m. Uppermost 27911 collected on 19 Nov 1930 liom the location given in the edge of Sonoran and Chihuahuan desertscrub, grass- protologue.This specinren(#191687) was annotatedas the prob- able type (i.e.. lectotype; by both l-ouis Wheeler (in 19,12)and land, and oak woodland in Arizona along the Sonora Rogers McVaugh (in 1992;, and wc arc in agreententwith thent. border from the Baboquivari Mutthis taxon is weakly defined.The variation in cluding those fi

Mpio. Cajeme: cerro about l0 nri S ol Ccl. Obregtin. Ocntrt' 112<1. EupHoBete HUMAvENSTSBrandegee, Zcte 5'.208. 1905. Mpio. Navojoa: micrcwave tower rd on C'crro Pricto. ca. 9 mi E of' Eumecanthushumayensis (Brandegee) Millsp., Field Navojoa on Alamos rd, Van l)evetuler & Vurt I)eytnder 92 167. Mus. Nat. Hist.. Bot. ser. 2: 414. 1916.-TYPE: M6xico, Sinaloa, Culiac:in, I Oct 1904, Brandegee Eupnonste cRAMINEAJacq., Select. Stirp. Amer. Hist. .r.n. (lectotype [designatedby Hufl 1984, p. 1025] l5l . l'763. var. GRAMINEa,.Adenopetalum gramineum UC[#110009], not seen, photo [Field Mus. neg. (Jacq.) Klotzsch & Garcke, Abh. Kcinigl. Akad. Wiss. 582871I; isolectotypeF[#1961 58] !). Berlin 1859 [Phys. Abh.]: 47. 1860. Eumecanthus gramineus (Jacq.) Millsp., Field Mus. Nat. Hist., Bot. Erect leafy summer/fall annual closely resembling ser. 2: 413. 1916.-TYPE: Columbia, Cartagena, E. graminea but readily separable by the possession Jacquin s.n. (lectotype BM[#510672]1, designatedby of a glandular-pilose indumentum. Tropical deciduous McVaugh 1993, p.233). forest; 400 m. In Sonora known from a single collec- VOLUME16, NUMBER Euphorbiaceae of Sonora 33 tion; also Sinaloa to Michoacdn, the Cape Region of desertscrub in northwestern Sonora from Puerto Pefl- Baja California Sur, and reporred by Huft (1984, p. asco and Bahia de la Cholla southward to Cerro Te- 1025) for Venezuela. popa and on Isla Tibur6n, near sea level to ca. 650 m; farther south, in the Hermosillo-Guaymas region, it is Mpio. Alamos: SE edge of Sierra de Alamos, Anoyo las Rastras, replaced by the closely related E. calfornica. Van Devender 93-1167. Also southern California and both states of Baja California. Plants from Islas San Benito tend to have slightly Eupnonste MACRopus(Klotzsch & Garcke) Boiss. in larger appendages and seeds. They have been segre- DC., Prodr. 15(2): 52. 1862. Anisophyllum macro- gated as Euphorbia benedicta, but the differences are pum Klotzsch & Garcke, Abh. Kiinigl. Akad. Wiss. slight, and we treat them within E. misera. Berlin 1859 [Phys. Abh.]: 33( 34). 1860.-TYPE: M6xico, fHidalgo, Real del Monte et Cerro Ventol, Mpio. Pucrto Pciiasco: Punta Pefrasco,Felger 90 6-1,Shreve 7597', Ehrenberg (B, probably destroyed). Bahiadc la Cholla.sand dunes. Lehto -17 l1(ASU). Mpio. Caborca: dunes 2 nri N ol Puerlo Lobos, 7'urner 60-'15. Mpio. Pitiquito: Cemo Eupfutrbiu ltlummtrat,S. Watson. Proc. Amcr. Acad. Arts lU: l9-5. Tcpopa. I'-elger 2O261. 1883. TYPE,: Llnited Statcs,Arizona. Huachuca Mts.. Scntincl. Tanncr's Canyon. Julv 1U82.Lentnutn 2,32,1 (holotype GH!). ELrpHonsraocyMorDEA L., Sp. Pl. 453. l'753. Aniso- Eutthrtrbia lilrtrnri.s S. Watson. Proc. Anrcr. Acad. Arts l8: l5l. phyllum ocltmoideum(L.) Haw., Syn. Pl. Succ. 16l( f 883. Z-r'3o7;/tlllidiunr bilttrnrr, (S. Watson) Arlhur. Torreya I l: 162). 1812. Leptopus oc,,-moideus(L.) Klotzsch & 260. l9ll. TYPE: M6xico, San Luis Potosf. San Miguelito Mts., 1876, SchulJiterlt60 & U62 (synrypes GH!. ,9f;(/was an Garcke,Abh. Ki;nigl. Akad. Wiss. Berlin 1859 [Phys. notated by McVaugh to be chosen lcctotypc in thc tirrthconting Abh.l: 45. 1860. EumeconthLt.socy-tnoideu.s (L.) Flora Novo Cialiciana).Anothcr syntypc. lSan Luis Potosfl. rc Millsp., Field Mus. Nat. Hist., Bot. ser. 2: 414. gion of San Luis Potosi,22"N, 6000 8000 ft. Parn .& I'ulrntr 1916.-TYPE: "Habitat in Campechia.Housfton]" 806 (GH!), is not 1i. md(ropus but insteadappears to be r species (neotype by McVaugh 1993. pp.228-2291 ne'ar ['.. gnttnint'u. Iselected BM, not seen,photocopy RSA!). For additional synonymy see Huft 1979. pp. 233 23,1. I:ttltlutrbia u\tn)it(.\ Fisch. & C'. A. Mey.. Inrl. Scnt. Hort. Pctrop. Perennial herb from a thickened, tuberous root, the l: -1-1(.15i. lr8J5.I:tttnet tttttlttt.s tt.stnritt'.t (Fisch. & ('. A. Mey.) Millsp.. Ficld Mus. Nat. Hist.. Bot. scr. l: -1I-1. l9l(r. TYPE: leaves opposite or rarely ternate; July September. Ciro*n in St. Pctcrsburg.apparcntly frorn sccclcollccted by Kar- Eastern Sonora; pine-oak woodland and mixed conifer *inskr at "'fanrpacoala" lMdxico. San Luis Potosi, Tampacu- forest: 1.100-2100 m. SoutheasternArizona to Central alab] tholotvpcpresurttably LE. not seen). America. F,ultltorbiuu:troit(.\ Fi:ch. & ('. A. Mcy. t.t. lt<'ttntltltt'rtdiculutu Euphorbia macropus is highly vuiable in size and l\'lillsp..Ficltl MLrs.Nat. Hist.. Bot. scr. l: lu. ltt9-5. TYPE: Mcxico. Yucutiin.IJ slopesof Cerro Crande-.Izanral, l-l Jan 1t395. in leaf shape. Euphorbitt rttust'it'ola Fern. has been Millsytu,slt6J {holotypeFl#19697 ll!). treatedas a synonym, but it is a distinct speciesknown Iiultfutrbiu cttliudiurttt Brandcgcc. Zoc 5: )0'7. 19O5. EunteLuntltus only from the vicinity of Tepoztl6n, Morelos. It differs t ttfi'uliurtus{tsrandcgcc) Millsp.. Ficld Mus. Nat. Hist., Bot. scr. by the possession of alternate, serrate to serrulate low- 2: .ll-1. 1916. TYPE: M6xico. Sinaloa.Cofradia. 20 Oct 1904. er leaves and less tuberculate seeds. Rntnde.qct.r.r.(holotypc UC[#l 100'+'{]not seen.photo US!: iso typc Fl#l96l59ll). Mpio. Y6com: hills ca. 1.5 knt W ot' Yicora. 28"22'-10"N. Delicate annual notable fcrr the fingerlike divisions I L)8"56'.15"W.Ste innuutn I () l I . Mpi

EupHoneresrNALoENSrs Brandegee, Zoe 5:208. 1905. East-central and southeasternSonora and western Chi- Eumecanthus sinaloensis (Brandegee) Millsp., Field huahua to Morelos. northern Guerrero and San Luis Mus. Nat. Hist., Bot. ser. 2: 415. 1916.-TYPE: Potosf. M6xico, Sinaloa, Cerro Colorado, 1 Nov 1904, Mpio. Y6cora: upper Barranca El Salto. Rio Yaqr.ri Brandegee s.n. (holotype UC[#l10010], not seen, drainage, edge of Mesa El Campaflcro, f-elger 91-188, Steinrnantt 102O.Mpio. Al- photo GH!; isotype F[#196160]!). amos: Siena Saguaribo.ca. 3 knr W of Saguaribo(by rd to tjl Clhi- ribo). vic. of 27"19'N. 108",11'W.Steintnuntt 9-l 2-18. Summer-fall annual with relatively conspicuous white appendages. In Sonora known only fiom oak EupHoBslR SLIBRL,NTFoRMIs and pine-oak woodland on the Sierra de Alamos where fas subrenifttrme] S. Wat- son, Proc. Amer. Acad. Arts 21 439. 1886. Eume- it is frequent at elevations of ca. I100 1700 m. Also canthus subreniformi.s (S. Watson) Sinaloa and western Durango. Millsp., Field Mus. Nat. Hist., Bot. ser. 2: 415. 1916. Euphorbia Mpio. Afanros: Sierra de Alantos. Steitttrtunn 9-1109, F-ishbein oc'ymoidea L. var. .subreniformi.s(S. Watson) Mc- t9-t I . Vaugh, Contr. Univ. Michigan Herb. 19: 229. 1993.-TYPE: M6xico, southwestern Chihuahua. EupHoReras()NoRAE Rose, Contr. U.S. Natl. Herb. l: Hacienda San Jos6,25 mi S of Batopilas, Aug 1885, 356; fig 10. 1895.-TYPE: M6xico, Sonora,[Mpio. Palmer 60 (syntype GH!). Another collection is cit- Huatabampol, Agiabampo, 3-l-5 Oct 189O,Palmer ed in the protologue: Southwestern Chihuahua, 760 (holotype US[#2089 1 l ] l). Frayles, 1885, Palmer 292; we were unable to find this at GH, but there is a specimenat NY Leafy summer-tall annual, notable firr the long, se- [!1. taceous stipules and undivided styles: mostly August Delicate erect annual; August November, rarely in to December.Shady understclryin thornscruband trclp- spring. Oak and pine-oak woodland; 700-1t300 m. ical deciduous forest: 200 750 m. Central Sonora to North-central to s

EupHonsrR xANrI Engelm. ex Boiss. in DC., Prodr. species is known in Sonora from a single collection I5(2): 62. 1862. Based on Euphorbia gymnoclada made in the shade of tropical deciduous forest with Engelm. in A. Gray, Proc. Amer. Acad. Arts 5: Ipomoea arborescens, Hamelia xorulensis, and Quer- 171(-172). 1861; not Euphorbia gymnoclada Boiss. cus tuberculata:94O m. It appears to represent an un- 186O. Aklema xanti (Engelm. ex Boiss.) Millsp., described species allied to Euphorbia hexagonoides Field Mus. Nat. Hist.. Bot. ser. 2: 415. 1916.- but differs in being perennial and having longer and TYPE: M6xico, Lower California IBaja Califbrnia narrower appendages. We know of only two collec- Surl, Cape San Lucas, Aug 1859-Jan 1860, Xdntus tions of this Euphorbn. 111 (holotypeMOI). Mpio. Alamos: E-facing slope in Arroyo Santa Bdrbara, above ELrlthorbiantrallilbru M. E. Joncs.Contr. W. Bot. l8: 50. 1933. " Ranchito" carnp. 27'05.8'N. I 08'.13.3'W.J enk i ns g-5--l-l-1.-SrNA- TYPE: Mdxico, Lower Calrfornia ltsa.jaCalrlirrnia Surl. Sierra l

Shrub to 2.5 m tall with semisucculentstems and Subgenus Chamaesyce Raf. 1: Chamae.sl,ceS. F. quickly drought-deciduous leaves, the appendages Grayl showy, white aging to pink; October May. Sonoran (these desertscrubalong the Gulf Coast of Sonrtra in sandy- Annuals, perennial herbs usually also flow- gravelly soils fiom Bahia San Carlos and Miramar ering in the first season),or rarely shrubs;growth sym- just near Guaymas also farther north fiom the vicinity of podial, seedling apex abortive above the cotyle- Bahia Kino to the vicinity of Puerto Libertad: near sea dons. Photosynthetic pathway Cr. Leaves opposite, level to ca. 500 m. Otherwise known from Baia Cal- with Kranz anatomy and usually with asymmetrical ifbrnia and Baja California Sur. bases; stipules usually conspicuous and membranous. Glands (2 )4: appendagesusually present; seeds (in ours) ecarunculate. Mpio. Cuayn.ras:adjace nt to Estcro Soltlaclo. /jc1,(,er,\4-.52-1. Mpio. Subcosmopolitanwith 250-300 species,reaching its "Scri Hcrntosillo: Pass.".1.I nri hy rd W ol RanchoNoche Bucna. greatestdiversity in M6xico where about 100 species I'tlger 16972. Mpio. Pitiquito: lJ rrri hy rd I: ol'Pueflo Libcrrarl. 'l'unrrr occur; 36 species and two additional varieties docu- Hu.stinu.sc* 65 12. mented tbr Sonora.Seeds are diagnosticand often nec- essary for identificationt fortunately they are usually EtrpHonsr,Asp. I presentwith a specimen.Most herbaceousspecies are Erect, perennial herb to ca. 0.5 m high, leaves op- commonly known as golondrina. References:Wheeler posite, linear; reproductive at least in October. This l936. 19.11.

Ciyathiain dcnse, subcapitate,leallcss cynrosc clustcrs. 2. Shrub: stipulcs subtcndedby numerous small glancls li. lonrcnlulosu 2' Hcrbsl stipulesnot suhtcndcdby glands. 3. Hcrbagc with pilose, fiequently ycllow hairs nrostly 0.-5 1.2 rnm long .....E.hirta -1. Cvnrcs tcrrnirrll as wcll as axillary: sceds0.7 0.9 nrnr long, pale and pinkish . I:. hirru vur.hirtu -1' Clnrcs r-rsuall'r'onlytcrrrrinal: seecls l l 1.2 rrrrnkrng. chrk and brownish Fl. ltirtu vLrr. n()(e,t.\ 1' Hcrhagt-glrhrous or with white. mostly apprcssedhairs less than 0.5 rnrn long. -5. Percnnial hcrb (but reproductive in the tirst ycar)t herbage and capsulesglabrous or pubescent:stipules laciniate- pubcsccnt. slender, separate or questionably unitcd at base: seeds narowly ovoid, the angles sharp li. <'ttpitelluta -5' Annuall herbage and capsulcs glabrousl stipules c-ntirc.broadly deltoid, clearly united: seedscorpulcntly ovoid, the anglcsroundcd .... L:.ht'pericifbliu l' Cyathia solitary in thc axils of leafy shoots. 6. Leaves strictlV entire 7. Stcms prostrate.ofien rooting at nodes; stipulcs unitcd into a -tlabrous.white membranousscale 8. Herbage pubesccnt. E. uluttttztulis 8' Herbage glabrous. 9. Perennial:involucres more than I mm wide. with 15 30 staminate aeTldac:: naked eye l:-:::' ::'"1':.."::T"ili,,'|,)!i,,"," 9' Annuall involucres0.6 1.0 mm wide, with l0 or fewer staminateflowers; appendagesinconspicuous E. serpens 7' Stipules not united into a glabrous, white membranous scale. 10. Herbage glabrous; leaves linear (rarely narrowly spatulate), 1.5 mm or less in width, the base not noticeably asymmet- rical. ll. Ultimate branches ca. 0.1 mm or less in diameter (sorry, see discussion)l styles divided . . . . . E. gracillima 11' Ultimate branches 0.1-5 0.25 mm in diameter; styles evidently undivided . . . . . E. revoltrta l0' Herbage glabrous or pubescentt leaves variable, seldom linear, more than 1.5 mm wide, the base usually asymmetrical. 12. Herbage with appressedhairs only. 36 Steinmann and Felger ALISO

13. Seeds quadrangular, smooth to rugulose . . . . E. melanaclenia l3' Seeds terete, encircled by conspicuous transverse ridges E. pediculifura 1u1.Leaves ovate to obovate or lanceolate . . . E. pediculifera var. pediculifertt 14' Leaves linear . . E. pediculif?ra var. Iinearifolia l2' Herbage glabrous or with at least some spreading hairs. 15. Ovaries and capsules pubescent. 16. Appendages divided into triangular, pointed segments, the involucres thus appearing "star-shaped" E. setiloba l6' Appendages rounded to broadly lobed or absent. 17. Hairs glandular; involucres urceolate or nanowly turbinate. narowed or constricted at apeX . E. ariz.onica l7' Hairs not glandularl involucres obconic to campanulate,not narrowed or conslrictcd at apex. Itl. Seed smooth to rugulose. 19. Glands oval,0.3 or more mm wide. with petaloid appendagesbut these somctimes reduccd orrarelyabsent .... E.JxtlvLttrpu l9' Glands usually round and punctifbrnr.0. l-0.2(-2.-5) mm wide, without petaloid appcndages E. tnit rt)nt.,td l8' Seedsstrongly rugose and usually with conspicuousridges. 20. Capsulesunifbrrnly pubescent . E. petrina 20' Capsulcs nlost densely pubcsccntalong the keels and glabrate between ll. Annual: stenrstcrctc or merely flattened;appcndages glabrous ...... E.prostrale 2l' Pcrennialherb: stcrnswinged: appendagespubcscent . I:. alatocuuli.; l5' Ovariesand capsulesglabmus. 22. Seedsnlore than 2 nrnr long. 23. Sccds flattencd.itbout twice as long as widc, the back smooth. thc vcntral lace u'ith an clevated niid .dgc E. prutt..spenna 23' Scetlsovoid to nearly oblong. not at all flattened,the back sln(x)tht() nrugh. thc vcntral firce lacking an clct,atednrid ridge. f'1. Stcnts cncasedin a sandjacket; seedsround in cross scction,the surlacessln(x)th E. inctrtu 2'1' Sterttsnot encascdin sand; seeds'l-anglctl, thc surfacesrough . . F,.tnu ht.spermu 22' Seedslcss than 2 mm long. l-5. Annualsorperenni:rls;stipulcsusuallypubescentwrthveryshort,stiffhairslseedssnroothorrugulosc. 26. Cilandsoval,0.3 or Inorc ntm wide, with petaloid appcndagesbut these somctimes reduccd or r;rrely lrhscrrl .... E.ytlvt;arpu 2(r' Cilandsusually round and punctifirrm.0. I 0.2( 2.5) rnrn wide, without pctaloid appendagcs..... E. ntit ntttrcra 2-5' Annuals; stipulesoiten divided into tilifbrrn tlivisionsbut generallywithout hairs:sccds with transversc ridges. 27. Plants rnostly spreadingto prostratc:lcavcs lcss than l5 mm long; stipulcs distinct: glands 0.1 O.l5 rrrrrrwide: seedswhite-gray, namowly ovoid, the angles sharp [:. ubntnr.sittrttt 27' Plants ercct to rscending: lcalcs usually more than l-5 nrnr krng; stipulcs on larger stcms often unitcd into a triangular shcath:glands 0.2-0.4 mm wide; seedsusually blackish (only the angles consistentfywhitc gray). corpulently ovoid, the anglcs roundcd ... E. htssopiliilia 6' Leaves (at lcast when mature) serrateto scrrulate,although sometimcsobscurcly so or only at thc apex. 28. Ovarics and capsulcspubescent. 29. Glands 2 or 4: appcndagesrnarkcdly dissirnilarin size, or one pair abscnt. 30. Involucres usually with only 2 glands: appendagespubescent E. densifloru 30' Involucres with 'l glands: appcndagcsglabrous. 31. Annual; appcndagesof thc larger pair 0.9-1.5 mm long; capsulcs cxserted fiorn the involucrc; seeds with trrn\vchc sulei E. inlir i:u 3l' Annual or perennial; appendagesof the larger pair less than 0.6 mm long: capsulesnot exserted,the lower portion enclosedby and maturing within thc involucre; seedslacking sulci, merely dirnpled or rippled E. thvmtJitlia 29' Glands 4; appendages subequal or absent. 32. Perennial;glands 0.8-1.5 mm wide; capsulesuniformly pubescent;seeds 1.5-1.7 mm long E. leuLttphvlla ssp. (omcaacorum 32' Annuals or perennial herbs; glands 0.5 mm wide or less; capsules unifbrmly pubescent or most densely pubescent along the keels and towards the base; seeds 1.4 mm long or less. 33. Styles undivided E. sticto.spora 33' Styles divided at least part of their length. 34. Stems wingedl appendages present and pubescent E. alatocaulis 34' Stems terete or slightly flattened; appendages glabrous or absent. 35. Perennial with a thickened rootstock; appendages 0.4-0.9 mm wide; capsules glabrous to uniformly pubescent or very rarely most densely pubescent along the keels; seeds corpulently ovoid, merely nrgose. .... E.anychioides 35' Annual, the root not thickenedl appendages mostly iess than 0.3 mm wide; capsules most densely VOLUME 16. NUMBER I Euphorbiaceae of Sonora -)l

pubescent along the keels and glabrate between; seeds narrowly ovoid, with obvious transverse ridges ...E.prostrata 28' Ovaries and capsules glabrous. 36. Shrub;stipulesunited ...... E.maptlalenae 36' Annuals or perennial herbs; stipules distinct or united. 37. Seeds 1.5 2.4 mm long. 38. Stems with pilose white hairs . . E. serrula 38' Stems glabrous. 39. l-eaveslinear. symmetrical at the base;appendages conspicuous to the naked eye; seeds 1.7-2.0 mm long, the facets smooth betwccn the I to f'ew transverse ridges . E. florida 39' Leaves linear to ovate-lanccolate,mostly asynrmetricalat basei appendagesmostly inconspicuousto the naked cyel seeds 2.0 2..1 mm long, the facets granulated and without transverse ridges . . . E. trach,-sperma 37' Sceds less than l.-5 mm long. 40. Facetsof thc scedswith concavc depressionsseparated by distinct ridges. .11. Cocci of capsuleslaterally compressed.the tangentiallength greaterthan the width, the keel acute E. t'repu.sculct 4l' Cttcci ofcapsules not latcrally cornpressecl.the tangcntial lcngth equal to, or lcss than the width, the keel obtusc. ,12. Stipulcs on larger stems oficn unitcd into a triangular shcath: lcaves often serratcto serrulatcthelr entirc lcngthl Inature secdsusr-rall1'blackish (only the anglcs consistcntlywhite-gray) ... E. hvssopifolia '12' Stipulesdistinct. Iinear-subulatc:lcavcs se-natc()r \crrulate only at thc apcxi mature secdswhite-grar. 213.Herhagc glabrotrsor pubescent:stenrs tercto: lcaf sr-rrationsinconspicuous even undcr magnifr- catlon. not visible to thc nakctl c,l*c:trilns\ersc ridges on thc sccds deep, oticn interrupting thc dorsal rngle l-..tthrum.tiunu ,13' Hcrbage glabr,rus:\rcnr\ tr-tctc()r ulngL'Ll:lcat serrationsconspicuous. olien vtsiblc to the naked eyel transverseridgcs on thc-scecls shallo*. n()t intcrrupting thc clorsalanglc . E. scrprlliloliu 40' Facets of thc seeds snrooth to rugulosc-. 44. Percnniallcapsules and involucres usuallr pubcscent E. unychioides .1,1'Annualst capsulcsand involucrcs glabnrus. zl5. Leaves ofthc branchletsentirc. thosc ol thc ntf,ln \lcnt\ \cl-lltc: scedsO (r ().Rtnln long . . . E. radioloides .15' l-cavcsof-the branchletsand stcntsuith :ilrrilarrrrargins: sccds l.l I.-l rnnt long. -16. Plants less than 30 cnt tall: hc-rhagcglahrous: :tents tcrcte or wingcd: stipules lincar subulate, tlistinct: seedsnarrowly ovoirl. uhttish. !rnr\. to light bro*n . . . . . F,. scrptllilolia J6' Plants oltcn morc than 30 cnr tall: ht-rhageglabrous or pubesccntlstcrr] terete. stipules deltoid. with age usually unitcclinto a sheath:seeds corpulcntlr ovoicl.blackish (only thc anglcs whitish). -17. Sccds rugose I:. ttulans -17' Seedssmooth or laintlv transvcrsclvridsccl . Ii. ltionospenrut

EupHonste ABRAMSTANAL. C. Wheeler. Bull. S. Calif. nov.-TYPE: M6xiccr, Sonora, Mpio. San Javier, Acad. Sci. 33: 109(-l l0). 1934. Euphorbia pedicu- along MEX 16, 15.2 km by rd W of the Rio Yaqui liferaEngelm. var. abram.tiana (L. C. Wheeler) Ewan crossing, 28"34'33'N, 109'41'04'TV',ca. 700 m,25 in Jeps.,Fl. Calif. 2: 427. 1936. Chamaesyceabram- May 1996, Steinmann 861 (holotype siana (L. C. Wheeler) Koutnik, Madroflo 32: 188. ARIZI#3354681; isotypes BM, DAY ENCB, LSU, 1985.-TYPE: United States,California, Heber, June MICH, NY, IBUG, MEXU, RSA, USON). Fig.6-9. 19O4,Abrams 4097 (holotype DS[#33555]!). Herba perennis. prostrata; radix cylindrica. saepe crassa; caules Prostrate annual; mostly growing in response to usque 3l cm longi, valde alati, supra puberuli infra glabri; petioli summer/fall rains but in southern Sonora sometimes 0.3 l.l mnr longi, 0.3-0.5 mnr diametro; laminae ovatae vel ellip- ticae,pilosae.0.2 1.6cm longae,0.l5 l.l cm latae,basi obliquae, also in the spring. Sonoran desertscrub and thornscrub apice obtusae. rnargine integrae vel semrlatae: cyathia axillaria sol- in western Sonora, often disturbed areas;near sea level itaria; pedunculi 0.7-2.3 mm longi, ca. 0.2 0.3 mm diametrol in to 915 m. Extending into open or weedy woodland volucra obconica vel campanulata,pilosa, 0.7-1.3 mm longa, 0.6- vegetation in southern Arizona and expected in similar 0.8 mm diametro; glandulae .1, rubiginosae, 0. l-0. 15 mm longae habitats of northeastern Sonora. Southeastern Califor- (tangentialiter), 0.2 0.5 mm latae (radialiter); appendices semiorbi- culatae vel ovales, integrae vel sinuatae.0.2-0.3 mm longae, 0.3- nia, the Baja California Peninsula, and southern Ari- 0.5 mm latae. margo ciliato-hirsutae; flores d ca. 3,101 ovarium zona to Sinaloa. 3-angulatum;styli 3, ca. 0.2 mm longi. bifidi, clavati; capsulavalde 3-angulata, 1.4-1.6 mm longa. 1.5-1.9 diametro ad basi, carinae Mpio. Gen. Plutarco Elias Calles: Sonoyta, Felger 85-932. Mpio. laxe pilosae; columella 1.2-1.5 mm longa; semina ovoideo-quadran- Bavispe: Colonia Oaxaca, White 612. Mpio. Guaymas: Bahia San gularia, 1.0-1.2 mm longa, 0.5-0.6 mm diametro, valde rugosa. Carlos, Felger 85-1101. Mpio. Alamos: Yocogigua. Van Devender 93-1 150. Prostrate perennial herb often from a thick, gnarled, cylindrical root with many sprawling stems arising Euphorbia alatocaulis V. W. Steinm. & Felger, sp. from a cofiunon crown; stems to 31 cm long, conspic- Steinmann and Felger ALISO

lmm

\. 1*,.t< '-1 \+

lmm

Fig. 6 9. I'.uplurrbiuulot()fltuli.\.6. Habit. 7. Flowering branchlct.-tJ. Cyathium. 9. Seccl.All lhrnr .\tt,irtnrttttttli(tl uously winged, the lower surf-acemostly glabrous,the around the distal porticln clf the gland, semicircular to upper surface puberulent with hairs mostly under 0. I oval, 0.2-0.3 mm long, 0.3-0.5 mm wide, entire to mm long, glabrate in age; stipules distinct or united sinuate,white aging to pink, ciliate along the margin; into a deciduous white to hyaline membranous,trian- bracteolesrelatively numerous,included, entire or fim- gufar scale O.2 O.5 mm long and 0.4*0.7 mm wide, briate towards the apex; d flowers ca. 3-10, andro- the margin subentire to lacerate; leaves opposite; pet- phores glabrous; gynophore sparselypubescent below ioles 0.3-l.l mm long, 0.3-0.5 mm in diameter; the ovary, reflexed or erect, exserted O.7-2.'l mm in bladesovate to broadly elliptic, 0.2-1.6 cm long, 0.15- fiuit; ovary 3-angled; styles 3, ca. O.2 mm long, bifid l.l cm wide, inconspicuously palmately 3-5-veined ca. 3/4 of their length, the divisions clavate; capsule from the base, oblique at base, apex obtuse, pilose with broadly ovoid in profile, trigonus in cross-section,1.4- hairs 0.2-0.8 mm long: margin entire to minutely ser- 1.6 mm long, 1.5-1.9 mm in diameter at the base, rulate; cyathia solitary in the distal axils and forks of loosely pilose on the keels of the carpels (especially the stem, on peduncles O.7-2.3 mm long, ca. 0.2-0.3 below the equator) but glabrate between the keels, a mm in diameter; involucres obconic to campanulate, deep furrow in each sinus between the carpels; colu- O.l-1.3 mm long, 0.6-{.8 mm in diameterjust below mella 1.2-1.5 mm long; seeds narrowly ovoid-qua- the glands, pilose on the outside, the lobes triangular, drangular, I.O-I.2 mm long, 0.5-0.6 mm in diameter, ca. 0. I mm long, pubescent within, the sinus broadly orange-tan to pink-brown, with a high dorsal keel, base U-shaped, not depressed; glands 4, yellow-green to truncate, apex acute, the facets strongly rugose. red-brown, reniform with a conspicuous tangential Tropical deciduous forest and pine-oak woodland in trough, 0.1-0.15 mm long (tangential axis), 0.2-0.5 central eastern and southeastern Sonora; 325-1300 m. mm wide (radial axis); appendages forming a nng It often grows in the disturbed area along roadsides VOLUME16, NUMBER 1 Euphorbiaceae of Sonora 39

and on rocks in riparian habitats. So far known only in habit, produce roots at the nodes, and possessunited from Sonora but expected also in northern Sinaloa and sheathlike stipules. Euphorbia serpens differs by its southwestern Chihuahua. Reproductive from at least strictly annual habit, somewhat more glaucous leaves, March to October. slightly smaller cyathia (less than I mm wide), nar- Euphorbia alatocaulis is evidently related to Eu- rower appendages,smaller capsules,fewer stamensper phorbia mendezii Boiss., a widespread speciesoccur- cyathium (fewer than 10 vs. 15-30), and slightly ring in Florida, the Caribbean, Central America, and smaller and thicker seeds(l .0-1.2 mm long). An easy tropical M6xico as far north as Tamaulipas in the east and reliable way to distinguish between them is by the and Jalisccr and Zacatecas in the west. The two species size of the appendages. The appendages of E. albo- are united by possessingstrongly winged stems and marginata are conspicuous to the naked eye, while ovaries with the hairs mostly restrictedto the keels of lhose of E. .serpen.sare inconspicuous. the carpels, characteristicsunc()mmonly encountered Mpio. Pucrto Pefrasco:Pinacatc region. Sykcs Crater, I"elger 20020. in subgenus Chamue.syce.Euphorbia alatocaulis is Mpio. Guaynias: Ciuaymrs airpr-trt.helger,3.5 -ll-J. Mpio. Nacozari: distinguishedfiom E. ntende:.iiby its ciliate involucral El Rancho de'la Nrchu. f5 nti W ot'l,a Angosturir,White -1911. appendages,strongly rugose seeds,and lack of long, Mpio. Alanros: El Ranchcria crcssing ol'Rfo C-'uchujaqui,ca. 22.-5 spreadinghairs along the stems. knr S of Alarrros on rcl to El Clhinal. Vurt l)<'r't'nder & Vun [)everuler The specific epithet alcttocoulis ref'ers to the con- e) I 177. spicuously winged stems. Errprroner.rANyc'HrorDL.s Boiss., Cent. Euphorb. 12. I'arott'pes. Mpio. Alarnos: Rio Cuchu.jaqui.11..1 krn Lrr air S ol' I tt60. Chuntaest'ce anychioide.s (Boiss.) Millsp., Alamos. Rancho cl Conejo (- R. E,l Corcovatlo). l(r'54'-15"N. Field Mus. Nat. Hist.. Bot. ser. 2: 408. 1916.- 108'55'W Vurt 92,59-l'. l)eycndtr Rio C'uchujac1ui.l.(r krn Ntj ol' TYPE: Mdxico, Guanajuato,Villalpando, 1829, Sabinito Sr-rr.27.(X)'05"N. l0tt'47'0t3"W. Vun I)tytttdL,r 9.1 ll,\.t. Mdttde:. (holotype Canyolr o1'thc Rfo Guajari'rv.ca. ,1 knr upstrcanr(nortlrw,irrd) Iirrn G-DC, not seen, fragment I-os Agrraros.27"39'36"N. l0lt'57'58"W. Fal.q<,r91 7/. Mpio. Yct F[#t968.1,+l!). cora: akrng MEX 16. 1.5 knr by rd W of Rio Maycoblr crossing. l:trltlrrtrltitt ungclrrr. ex Iloiss. in DC., Prodr. l5(2): 39. .\tt'irttrrttrtrt9O2'. cir.23 knr E, ol Y6corir. Los I)ilares.Arrovo [-os ltilo.sula 1861. ( /rrurrrrlrr

(1941, p. 243) lectotypified this species with a col- 2: 411. 1916.-TYPE: United States. Arizona, near Prescort. 19 lection made by Schott in Arizona during November, June 1883, Rusb.,-822 (holotype possibly destroyed in the 1906 fire at CAS because there is no specimen either there or at NDCI 1856. The lectotype and aforementioned fragment isotype US[#221761 ). (MO!#469O61 are mounted on the same sheet !). De- Euphorbia capitellata Engelm. var. lari.flora S. Watson, Proc. Amer. spite the fact that the November, Arizona material Acad. Arts 24:11. 1889. TYPE: M6xico, Sonora, [Mpio. Guay- may have been available to Engelmann at the time masl, Guaymas, high mountains, 1887, Palmer 210 (lectotype of description and that the July, Sonora specimen is GHl. chosenby Wheeler 19.11.p. l7:l). Euphorbia pvt'nanthema Engelm. forma serrattt Millsp., Proc. Calif. far from complete (though readily identifiable as E. Acad. Sci. ser. Il, 2: 224. 1889.-TYPE: Apparently the same arizonica), we do not see how another collection collecticrnas the type of E. gentiniloba (bclow) and possibly the could justifiably serve as lectotype when only the same specimcn. July, Sonora specimen was cited by Engelmann. Iiultlnrbia geniniloba Millsp., Proc. Calif. Acacl.Sci. ser.II. 2: 228. 1889. TYPE: M6xico, Lower California IBaja Califbrnia Sur]. Euphorbia t,ersicrtktrGrccne. Bot. Gaz. 6: 18.1( 185). 1881. Cfta- Pozo dc Ios Dolores, -5 Apr 1889, Brandegtt' .s.ri. (holotype tnee.sr('('versit'olrtr (Grecnc) Norton in Tidcstr., Contr. LI.S. Natl. Ff#I96l'12tI). Hcrb. 25: 345. 192,5. TYPE: Llnited Stares.Arizona. San Fran- F,uphrtrbia glutlio.stt M. E. Jones. Contr. W- Bot. l5: 111. 1929. cisco Mts.. 3 Sep 1880. (]reenc .s.rt.(holixypc NDG[#296171!). TYPE: M6xico. Sonora. [Mpio. Guaymas], Guaymas. 2 Nov F,uphorhiu portulonu S. Watson. Proc. Ar.ner. Acad. Arts 24: 7-5. 1926. .ltme.s2261-l (lcctolypc POM[#162-575. thc plant marked 1889. Clnmucsttc lxtrtukuur (S. Watson) Millsp., Ficld Mus. "A'l!, heredesignated). Whcclcr (19-15;19.11, p. 174)treated lf. Nat. Hist.. Bot. ser. 2: .{ll. 1916. TYPB: Mdxic0. Sonora. gludio.sttas a svnonynl ol'I.- fttpit(lldtri. What he did not ntention IMpio Guaymas]. Guaynras.island in harhor. Oct 188'7,Pulncr and possibly dicl not notice is that thc hokrtypc sheer (i.e., thc -12l (holotypeCHI). one rt P()M ex Joncs's hcrbariurrr)contains pieccs of both 1r. Euphorbia Jturi.simanuMillsp.. Proc. Calif. Acacl. Sci. ser. ll, 2: utpit(IIuIu untl Ii. pedit uIift'ru vur'. Iitu,urilitIia. Sirnilarlr. Jones's 225( 226). l8fl9. ('/ranraa,nctJturi.sitrturtrt (Millsp.) Millsp.. Fielcl description.whilc bascclpriniarilr on I:. cttltitellula,tiocs contain Mus. Nat. Hist-.Bot. scr.2: .lll. 1916. TYPE: M6xrco. l-owcr elenrents ol' I'.. ltclir ulili,rrr. Thc scccls * ith "cross ribs lvl.rich Calilbrnia lBa.ja Cialitornia Surl. Purfsinra. ll Feb 1889. Bran- lbrrn rathcr dccp pits. antl *hich so through thc angles" applies de.gtt,.t.tt. (holotypc Fl# 196121lt l. rrnfy t0 1j-.ltedi< ulifi'nt. Bccauscthc larlcst plant 0n thc type sheet I')upfutrbia col/ila Brandcgcc. L)nir'. Calil'. Publ. Bot. 4: ltl4. of F).glulitxtt is 1,. cttltittlluta. and hccauscJones's description l9l l. TYPE: Mc

Contr. Gray Herb. 127:61;plate 3C. 1939.-TYPE: totype NIO[#149820]!, chosen by Wheeler 1941, p. M6xico, Sonora, [Mpio. Alamos], Gi.iirocoba, 13 138). Nov 1933, Gentry 789M (holotype GHI). Erect to ascending annual with large, conspicuous Warm-season erect to ascending annual with the appendages and narrow leaves that become revolute cocci of the capsules laterally compressed (appearing with age; July-December. Widespread in Sonora ex- somewhat winged). Tropical deciduous forest and oak cept the northwestern portion of the state; Sonoran de- woodland in southeastern Sonora; 400-1000 m. Also sertscrub, thornscrub, tropical deciduous forest, and Sinaloa. grassland; near sea level to 900 m. Jalisco to southern This species is closely related to E. hl,ssopfolia, Arizona. consistently differing only by the very narrow cocci of the capsules. Mpio. Alan.ros:San Bernardo.Gentn'2279: Sierradc Alamos, along the rd oppositeParque El Chalat6n,27"00'45"N. 108"56',+0"W.Sr.,in- Mpio. Rosario: Mesa la [-agunita.]7"5ti'20"N. 109"06'30"\l'.6 Nov ttrunn 950. Mpio. Guaymas: strand at Estero Soldado, Felger 84 (;er?1r1 1986, Murtin et ul. s.rt. Mpio. Alanros: 3 krn by rd N ol'Cliirocoha 4O-5.Mpio. Caborca: Cerro del Viejo southwest of Caborca, along the rd t

(iRACrrLLIMA Eupuonstr DENSIFI-oRA (Klotzsch & Garcke) KI

For additional synonymy sec Wheeler 1939, p. 68. pantropical weed known in Sonora by a single collec- tion from a ruderal area in Annual or short-lived perennial herb, mostly erect tropical deciduous forest. to ascending but sometimes prostrate, the stems often Mpio. Alarnos: Waste area beside a strcet in Alamos, 1OOm, Jenkins densely pubescent with conspicuous long, yellow, 9-t, t00. multicellular, spreading hairs; reproductive nearly any time of year. Tropical deciduous forest, grassland, oak EupHonsra HyssoprFor-rAL., Syst. Nat. (ed. l0) 2: woodland, and the eastern edge of the Sonoran Desert; 1048. 1759. Anisophv-llumhvssopifulium (L.) Haw., most of Sonora except the northwestern and west-cen- Syn. Pl. Succ. l6l. 1812. Chamaesycehyssopfolia tral part of the state, characteristically in disturbed ar- (L.) Small, Bull. New York Bot. Gard. 3: 429. eas; 40-1400 m. Warmer regions of the world. 1905. TYPE: Jamaica, Brown in Linnaean Her- barium 630: 9 (holotype LINN, not seen, Linnaean Mpio. Nacozari: Rancho de la Nacha. Whitt 10117.Probably Mpio. Herbarium microfiche!). La Colorada: l l rni Il of Willard. bctween Hennosillo and Coloraclo. Wiggins & Rollin.s29-1. Mpio. Cucurpc: Palnr Canyon, ca. l7 mi Euplutrbiu.Torir,rrlMillsp.. Prttonia 2: 89(-90). 1890. Clrunue.sttt SE of Magdalena on rd to (ir-rcurpe, l:l Aug 1983, Vun l)ev,entler & jonc,sii(Mrllsp.) Millsp., I.'icldMus. Pub. Bot. 2: '110. 19t6. L,iber s.n. Mpio. Alantos: El Ciuayabocrcssing of the Rio Cuchu TYPE: L.lnitcdStatcs. Arizona, Bowie. l7 Sep 188,1,.tones 1217 laqui. l4 knr by air E,SEol'Alunros. Stcinnunn 9-l -117. (h()lotvpc Ff#l 9(15921I ).

For atlclitionalsynonyrlrv scc Whce'lcr ltl.1l. p. 1.11. EtrpnoRetR HIRTA L. var. NOcENS L. C. Wheeler. Contr. Gray Herb. 121: 10( 7l). 1939.-TYPE: M6xico, Warm-weather annual to ca. I m tall with one to Michoaciin, vicinity of Morelia, Loma del Zapote, severalerect to ascendingmain axes.Sitnoran deserts- 1850 m, ll July 1909, Ars?ne 30-18(holotype crub, tropical deciduous fbrest. and oak woodlandl us[#1002124]!). widespreadin Son,I.'rlgt,r 91-11-1. cent Chihuahua; ranging to Michoacdn, Estado de Mpio. Na coz-ari:El Rancho dc la Nacha, 25 nri W of La Angosttrt. Whitc M6xico, and San Luis Potosf. -19l,9.Mpio. Yi'cora: Pueno de la Cruz. N basc of Mesa (iantpanero, This well-marked variety differs fiom var. hirttt by 21t"22''1I"N.I09"02'20"W. Vutt l)eytnder 96176. Mpio. Cuayrnas: the characteristicsgiven in the key, and occurs at high- (iuiryrrtrs, 188J. I'ultncr,Y2. Mpio. Alarnos: Sicrra Slguariho. ca. I er elevations. In additicln,plants of var. nocens from krrrby air SE of El Chiribo. ca. 27"17'30"N.108'.1 I'i*. Stt,irtnttttttt 9-t 290. our region tend tct have a more fibrous, wiry, and bet- ter developed root system but with the tap root ob- EtrpHonera TNCERTA Brandegee. Proc. Calif. Acad. Sci. scure. It is sometimes confused with Euphorbia lineata ser.Il, 3: 17l. 189l. Chanutesyceinterto (Brande- S. Watson, fiom which it is distinguished by the nar- gee) Millsp., Field Mus. Nat. Hist., Bot. ser.2:'109. rowly ovoid (vs. corpulently ovoid) seedswith sharp 1916.-TYPE: M6xico, Lower Califirrnia Cal- (vs. rounded) angles. [Baja ifcrrnia Surl, La Paz, 5 Nov 1890, BrandeRee .t.n. Mpio. Ydcora: 4. I nri W of thr'Chihuahua bordcr.9..1rni E of (holotypeUC[#l 105I U]l). Maycoba on MEX 16. in Arroyo La Ciernagaclc Carnilo. u tributary Semiprostrate nonseasonal annual to possibly of the Rio Yepachic,2U'26'06.1"N. lO8'3-l'36.u"W.t"e!.qer 91 -126: short- Y6cnrr, Stcinnuttttt /00-5: bekrw Mesa Cirantlc. closer to Ye

Robust erect to ascendins warm-season annual. A Eupnonern rNDrvrsA(Engelm.) Tidestr., Proc. Biol. Soc. VOLUME I6. NUMBER I Euphorbiaceae of Sonora +J

Wash. 48: 40. 1935. Euphorbia dioeca H. B. K. var.? Subspecies comcaacorum consistently differs from indivisa Engelm. in Torr., Botany of the Boundary, ssp. leucophl,lla by possessinglarger seeds (1.5-1.7 [in Emory, Rep. U.S. Mex. Bound. 2, pt. 1]: 187. mm long vs. 0.9-1.3 mm long). In addition, the leaves 1858. Euphorbia adenoptera BerIol. var. [as B] ln- of Sonoran plants have well-developed petioles and divisa (Engelm.) Boiss. in DC., Prodr. l5(2): 49. blades with oblique bases. These characteristics are 1862. Chamaesyce indivisa (Engelm.) Millsp., Field only rarely encountered in the Baja California plants, Mus. Nat. Hist., Bot. ser. 2: 387(-388). 1914.- on which the leaves usually lack conspicuouspetioles TYPE: United States, New Mexico, Copper Mines and are amplexicaulis with cordate bases. Otherwise [neiLr Bayard, ca. 25 km E of Silver Cityl, 20 Aug the two subspecies are very similar, and both are re- 1851. Wright 1845 (lectotype l4OL#1446701!). Two stricted to coastal dunes. They are compared in figures collections were cited in the protologue, including the I 0-l 3. one above. Millspaugh (1914, p. 387) statedthat the The subspecific epithet comcaacoram honors the "type [is] in [the] Gray Herbarium," but since En- Seri Indians, who call themselvesthe Comcaac ("The gelmann probably did not see this specimen, it should People"). The taxon's geographic range is within the not serve as the lectotype. lnstead, we treat Wright traditional territory of the Comcaac. lB45 at MO (ex Herb. Engelmann) as the lecbtype. Pdrutlp(.\. lsla Tibur(rn: Palo Ficrro, I''el,qer125-11. ca. I kttt N ol' Luttlttrltitt rnultilitlitxtt M. E. Jones,C'ontr. W. tsot. lll: -5.1.l9-1-1. Punta Willard. I"cl.ser 17719 (RSA)r Canal del lnfiernillo. Ittutrio TYPE: M6xico, Jalisco.Guaclalajara. La Barrancu. l7 Nov 1930. /0,9,92(RSA). Mpio. Hcrnrosilkr: ca. I nri NW of Tlstiota. 121.r,'ar .lttnc.s275 17 (holotypc P()M[#191633].I)()t sccr). phrxo [)AV!: )o87 l: ) nri N ol' fishing villagc on Bahfa Kino. Wig,qlri.i.l Rrtllin.v (ARIZ. ttSA)t -15 krn N ol Bahfa Kino. Stttnnter//: Punta isotypc MOI# | 0-1.1-119I I ). /6,3 Chueca.ca 20 rni N of Bahfa Kino, l0 Nov I97-1.Vart l)ct't'rtdcrtl Prclstrateto weakly ascending summer annual with al. .t.rt.,ca. I krn N of Bahia Kino. /tal,r;er,3,l-,3.5:I krn S ol Puntir the proximal pair of the appendagesmarkedly larger Ona.29"05'N. ll2'10'W. l7 Mar 19u7.Henit'.s.tt.. W cnrl ol'C'crrr (S than the distal pair, seedswith pits resembling deeply San Nicollisut S end ol'Liueso dc Ballcna bcach cnd of Bahfa Kitto). l' t l,q<'r 95()7. sunken lines. Upper margins of Sonoran desertscrub, Chihuahuandesertscrub, mesquite grassland, and pine- Errpu<)Rsr,rMA(ir)Ar-ENArr Benth., Bot. Vcly. Sulphur 50. oak woodland; 700-2000 m. Northeastern and east- 1844. Churutest't:e mugdalenae (Benth.) Millsp., central Sonora. SclutheasternArizona to western Tex- Field Mus. Nat. Hist..Bot. ser.2:41O. 1916. TYPE: as, and widespreadthrough Mdxiccl to northern Central M6xico, Lower California, [Baja California Sur], Bay America. of Magdalena, 1841, Hinds .s.n. (holotype K, not Mpio. Cucurpc: Palnr C'rrnlon.('crro C'irrtl dc Plata. 17.7 nri S[r ol' seen,photo RSA!, fiagment MO[#19099731!). Magdalena. ,1-5 Scp 19J6. \'tut l)tyutl<,r .& Miksirck.s,n. Mpio. Naco: N sidc and base o1'Sie rra Slrn Josci.cu. 5 krtt SSW

lmm

..,/ i;'t' it:: ,:e ,ti,,

ln tr tU r I 12 13

Fig. l0 13. F.trphrtrbia lcrcoJthrlltt. 10. Flranchlet of ssp. rttnu.ttttutrwn. I I Branchlct ttl ssp. lt'utolth.tlltt. 12. Scccl of'ssp. r'orn- (da()runr.-- 13. Seed ol'ssp. 1car.o7;/ir'11a.l0 ancl ll front Steinmann9//: ll ancl lJ tronr P(,fr'\'.r:\'r? J8. mentulosa are the only subg. Chamaesvce shrubs in ol- Bacoachi.SE o1-Ccrm la Cienegtrita. lO'5 1.5'N. 109"-55'W,Itr.ift, northwestern M6xico. bain 1219a. Mpio. Saric: granitic hills I mi S of Sasabc.Wiggin.s -59l-5(LJS). lsla San Pcdro Nolasco: NE sidc ol islancl.rocky ridgc ca.20 nt below sunrmit. Fclger 9657. Isla Tibur(rn: SW side of island. En- senada dc la Pena, l.-cltltr 177 I L EupHoRsrRMTcRoMERA Boiss. in DC., Prodr. l5(2): 44. 1862. Chamaesyce micromera (Boiss.) Wooton & EupHonern MELANADENTATorr., Pacif. Railr. Rep. 4: Standl., Contr. U.S. Natl. Herb. l6: 144. 1913. 135. 1851. Anisophvllum melanadenium (Torr.) TYPE: United States,[Arizona, creek descendingto Klotzsch & Garcke, Abh. Kdnigl. Akad. Wiss. Ber- the San Pedro Riverl, S Sep lS5l,Wright 1851(h

(194I, p. 196) report of it from Peru seems to be in species with densely pubescent ovaries; it has not been erTor. documented for Sonora. althoueh it is known from Contrary to Wheeler (1941, p. 194) and various oth- southern Arizona. er authors, Euphorbia micromera was first validly pub- Plants vary greatly in size and can be glabrous to lished by Boissier and not by Engelmann. By stating densely pubescent. Material from Arizona and New that Boissier "perhaps justly" segregatedWright 1854 Mexico previously recognized as Euphorbia vermicu- as distinct from .8. polycarpa and then going on to lata Raf . is essentially identical to, and appears best express doubt about the taxonomic significance of treated within E. nutans. As pointed out by Wheeler some characteristics Boissier used to distinguish E. mi- (1941, p. 153), E. vermiculara is distinct in New En- cromera from -8. polycarpa, Engelmann (1861, pp. gland and its vicinity, but is ill-defined in Arizona and ll0-l7 l) did not met the required criterion of ac- New Mexico, and a study of E. nutans and its relatives cepting the validity of this taxon. Thus, in Engel- will be necessary before the proper position of E. ver- mann's paper E. micromera is clnly a provisional miculata can be ascertained. name. It was validly published by Boissier one year later. Mpio. Cucurpe: E of Cucurpe, on Rio Saracachi,cienega near Ran cho Agua Fria. 5 Sep 19'76. Vun l)evender & Miksit:ek,r.n.. Mpio. Euphorbia mic'romera and .8. polycarpa are closely Y6cora: along MEX 16.4.8 km by rd SW of Puerto de la Cruz, near related, and their seeds appear identical. Especially in El Aguajito, 28"22' 16'N, 109"02'51"W Stuinmunn l0-i7'. A"roy<>El arid situations, E. polycarpa may produce glands lack- Kipor (Quipor). .just E of El Kipor on trail to Ticrra Panda (Las 'Iaunas), ing petaloid appendages,and the glands may be small- 28"2,1'N. 108"33'35"W Vun Dey'entler95,967. er than usual, making the plants somewhat difficult tcr pEDrcr.JLrFERA distinguish fiom E rnicrutmera. In such cases, E. po- Euptioneta Engelm. in Torr., Botany of lycarpa can be distinguished by its larger and oval the Boundary, [in Emory, Rep. U.S. Mex. Bound. rather than smaller and nearly circular glands. Bclth 2, pt. I l: | 86. 1858. var. eEDICULIFERA.Chamaesltce species vary fiom annual to perennial and glabrous to pediculferct (Engelm.) Rose & Standl., Contr. U.S. pubescent. In Sonora, Euphorbia micromera tends to Natl. Herb. l6: 12. 1912.-TYPE: fpresumably be slightly more numerous in drier habitats, while E. present-dayArizona, Santa Cruz Co.l, on the Son- polycarpa tends to prefer less arid habitats. oita [Riverl, l5 Sep 1851, Wright ]848 (lectotype MOI#1446111!,chosen by Wheeler 1941,p. 183). Mpio. San Luis R. C.: 25 mi E,ol San Luis on MEX 2. granitichill. helger l67O8l). Mpio. Cien.Plutarco Elias Calles:.1.5 mi N of Ccrrcr Euphorbiu irtt'oluta Millsp., Proc. Calif. Acad. Sci. ser. ll,2: Colcrrado,cinder flat, ht'lgtr 101l6B. Mpio. Puerto Penasco:Pucrtc) 221( 228). 1889. Clrutrutcs,-(einvolutu (Millsp.) Millsp.. Field Pefrasco,Felger 85 769. Mpi<:. Agua Prictu: Puerto del Molino Que- Mus. Nat. Hist.. Bot. scr. 2: 410. 1916. Euphorbiu pedituli.fbra nradcr,E of Colonia Morckrs. Whit( 15.15(MICH). Engelni. v,tr. itttrtlutu (Millsp.) l. M- Johnst.,Proc. Calil'. Acad. Sci. scr IV. l2: 1070. 1924. TYPE: M6xico. Lower Califbrnia (ho- EnpnoReh NUTANS Lag., Gen. Sp. Pl. 17. 1816. Cha- lBaja Califirrnia Surl, ComondLi.Apr 1889. Rrundegeer.r?. lotypeF[#1961451!). maesycenutans (Lag.) Small, Fl. S.E. U.S. 712, 1333. L)uphorbiuconjunctu Millsp.. Proc. Calil-.Acad. Sci. scr. II, 2: 227. "Habit. 1903.-TYPE: in N[ueva]. H[ispania]." Pre- 1889. Chamaesy-(e()njunda (Millsp.) Millsp.. Field Mus. Nat. sumably a Mexican Sess6 and Mogiflo collection Hist.. Bot. scr. 2: 40U. 1916. TYPE: M6xico. Lowcr Califbrnia (probably at MA, not seen). [Baja Calilbrnia Sur], Purisima, l2 Feb 1889, Brandegee s.n. (ho- lotype Fl#1961471!). Eupfutrbio preslll Ciuss.,Fl. Sicul. Prodr. l:539. ltt27. Chutnae.svte Euphrtrbiu pediculifuru Engelm. var. inorndtu Brandegee, Zoe 5: pru,.s/ii(Guss.) Arthur, Torreya I l: 260. 1912. TYPE: According 209. 190-5.-TYPE: M6xico, Sinaloa.Cofiadia. 19O4.Brandepee to Wheeler 1941, p. 1.1.1,"Palernio,ltalia,'l'txlunt (Praha'.,)." s.a. (holotype UC, not seen). Euphorbiu hvperit(oliu L. var. tommuni.r Engelm. in Torr.. Botany Iiuphorbiu verm(brmis M. E,.Joncs. Contr. W. Bot. l6: 23. 1930.- of the Boundary. fin Emory, Rep. U.S. Mex. Bound. 2. pt. l]: TYPE: United States,Arizona. Ajo, l8 Sep 1929, Jones 24856 188. 1858.-TYPE: United States, New Mexico, l85l 52, (holotype POM[# 195929]!). 'JMO, Wright 1842 in part (lectotype not tbund, choscn by Wheel er 1941,p. 144;isolectotype NY !). Annual to short-lived herbaceous perennial, pros- Euphorbia langsingii Millsp., Field Mus. Nat. Hist., Bot. ser.2: 376. trate to ascending; reproductive nearly any time of 1913. TYPE,: United States,Illinois, Chicago,6 Aug 1898,l-an- year. Sonoran desertscrub, thornscrub, sometimes in sing 102 (holotype F[#196688]!). oak-grassland, and occasional in tropical deciduous Erect to ascending annual; August-October. Oak forest; near sea level to 1150 m. Northeastern Sonora, and pine-oak woodland in the Y6cora region; l52O- and widespread and common in western Sonora, ex- 1740 m. Widespread from Central America to southern cept the Guaymas region where it is replaced by var. Canada. linearifolia. Southeastern California and Arizona The name E. maculata L. has been applied to this southward to Sinaloa and the Cape Region of Baja species(e.g., Wheeler 194L, pp. 143-150), but as clar- California Sur. ified by Burch (1966), the correct name is E. nutans. Brandegee's variety inornata was proposed on the Euphorbia maculata (: E. supina Raf.) is a prostrate basis of its appendage-lessglands. We have observed 46 Steinmann and Felger ALISO this characteristic on some Sonoran plants (e.g., Stein- forest, mostly on sandy soils; sea level to 925 m. El mann s.n.) and do not interpret it as taxonomically Golfo at the mouth of the Rfo Colorado and Puerto significant. Although the type has not been available Peflasco southward in western Sonora to Sinaloa, is- for study, we treat var. inornata as a synonym of var. lands in the Gulf of California, and the Baia California pediculfera. Peninsula. One collection from north of Bahia Kino (13 mi SE Isla Tibur6n: Tordillitos. Felger 15470. Mpio. Bacoachi: Sierra de los Ajos. 3 nri SE of Mututucachi. 3O'.1,1'N.109"59'W. l;i,shbein 2261a. of Rancho Noche Buena, Felger 14015) also appears Mpio. Puerto Pefrasco:Pinacate region.0.-5 km S Carnegie Peak. Icl- to be this speciesbut is anomalous in possessingcon- gt'r 19906:21 mi W of Sonoyta on MEX 2. Irhtrt 192.17.}'lpio. spicuous appendages. Guaymas: Sien'aLibrc. ca.2 knt by rd E of .junctionu'ith MEX l5 along rd to Micr()ondas Avrspas. 2tl'ltt'.50"N. I I l.01',13"W1.srciri- Isla Tibur6n: Teconrate, duncs ncar heach. /:r,/,qa ,99Ot1.Mpio. Al- ntuttn977b. Mpio. Alarnos: Moc(zari.27.13'lO"N. 109'06'30"W Wrn antos: [r slopcs of Sicrra cle Alanros, Saucito Canyon. Rancho lir I)et'endcr & Von I)t't't'ndt'r 92- I -196:Srcna dc Alanros. I u Aug 1992. Srerrita,6 knr by air SSW of Alamos. Vun [)cyerultr 9.1 /-196.Mpio. Sleittmuntt s.n. lJnrpafnrc:Playa clcl Sol ISE of lrmpalmcl. hal,qer85 1129. Mpio. San Luis R. Cl.:1.0 knr W fionr t:l Golfir de Santa Cllara.ca. l(X) rrr inland fl-rrnrbc:rclr. l'(lc(r 9-l 05. EupHoRerl prrDrcLrt-tFERAEngelm. var. LINEARIFOLTA S. '/6. Watson, Proc. Amer. Acad. Arts 24: 1889.- Euphorbia pionosperma V. W. Steinm. & Felger, sp. TYPE: M6xico, Sonora, [Mpio. Guaymasl, Guay- nov.-TYPE: M6xico, Sonora, Mpio. Y6cora, hills mas, high mountains.Sep 1887, Palnter 215 (lec- ca. 1.5 km W of Y6cora,28"22'30"N, l0fl'56'.15"W. totype GH, not seen,chosen by Wheeler 1936, p. l6tD m, 5 Sep 1996. Steirttrruntt1006 (hol

lmm

lcm

1mm

F'ig. l4-17. Eupfutrhiu piotttsspenn.u.1.1. Habit. 15. Cyathiunr. 16. Seed.dorsal view.-17. Secd. apical view. All trom Steinmann I 006. side, pubescent within, the lobes triangular, 0.3-0.6 fimbriate at the apex; d flowers ca. lO-25, andro- mm long, often lacerate into attenuate-filiform divi- phores glabrous; gynophore glabrous, reflexed or erect, sions, the sinus U-shaped, slightly depressed;glands 4 exsertedto 0.6-1.8 mm in fruit; ovary 3-lobed; styles (sometimes reduced to 2 or 3), dark pink to red, punc- 3, 0.4-0.8 mm long, bifid th-y2 their length, filiform, tiform to transversely oval, 0.1-O. 15 mm long (tan- slightly dilated at the apex; capsule gently 3-lobed, gential axis), 0.1-0.25 mm wide (radial axis); append- 1.8-2.1 mm long, 1.9-2.3 mm in diameter; columella ages absent or forming a rim around the distal portion 1.6-1.8 mm long; seedsplumply ovoid, 1.2-1.4 mm of the gland, semicircular to rotund, to 0.3 mm long long, 0.8-1.0 mm in diameter, blackish to gray to and 0.6 mm wide, entire, white aging to dark pink; brown, base rounded, apex obliquely obtuse, roundly bracteoles included, relatively few, filiform, entire to trigonous in cross-section with the two abaxial facets .+8 Steinmann and Felger ALISO serving as sides and the two adaxial facets together Mpio. Puerto Pefrasco: I mi S of Moon Crateq shifting dunes, Felgar serving as a side, facets convex, smooth or with 1901L Mpio. San Luis R. C.: El Golfo. beach dunes. Felser 75, 84. (1-)2(-3) faint transverse ridges, the angles of the seeds cordlike, often whitened, the adaxial surface poLycARpA with a conspicuous darkened line running from the EupHonsra Benth., Bot. Voy. Sulphur 50. apex to the base and a dark punctiform spot at the 1844. Chamaesycepolvcarpa (Benth.) Millsp., Pub. hilum. Field Mus. Bot. ser.2: 4ll. 1916.-TYPE: M6xico. Oak and pine-oak woodland, often in open grassy Lower California, [Baja California Sur], Bay of areasand rock outcrops, 1260-1700 m (to 1900 m in Magdalena, 1841, Hinds s.n. (holotype K, not seen, adjacent Chihuahua); August-October. Eastern Sonora photo RSA!). and adjacent Chihuahua. Euphrtrbiu polrcarytu Benth. var. las L\l hirtclla Boiss. in DC'.. Prodr. This species belongs to the Euphorbia h,-ssopifolia l5(2): .1'1. 1862. Chumae.stcepoltcurln tit. ltirtelltt (Boiss.) complex, and as with other members of this group, the Millsp. ex Parish,Carncgie lnst. Wash. Publ. 193: li0. l9ll. seedsare diagnostic. They are comparatively corpulent Cluttrutesyceron.rila Millsp., Field Mus. Nat. Hist., B()t. scr. l: and nearly smooth tn E. pionosperma. In Sonora it 112. 1916. TYPE: Llnited States, "Calitbrnia" Iprobably fronr the Cokrrado l)escrt, Whcclcr 1936, p. 4091, could be confused with E. hyssopifolia and E. nutans, 1u46, Fsnory .s.n. (lcctotypeC. not seen,chosen by Wheeler 1941,p. l9llisolec- but seedsof these speciesare conspicuouslywrinkled tcxypc NY!.t. or transversely ridged. In addition to the seminal dif- Euphorbiu inlcnrti.rtu S. Watson. Proc. Anrcr. Acad. Arts 24: 7'1. ferences,E. pionosperma is completely glabrouswhile 1889- ( huntut.r\'(( internri-\tu(S. Watsonl Millsp.. Field Mus. E. nutans and .E hyssop$blia are ofien, although not Nat. Hist., Bot. ser. 2: -109. 1916. I',ultltttrltiu7rolrrtlTra Bcnth. (S. necessarilyalways, pubescent. r^r. int(nni.ttu Watson) I-. C. Whcclcr. tsull. Ton. Bot. Club 63: .:112.1936. I'YPE: Mi'xico. Sonora. {\Ipio. Cuurnrasl. The specilic epithet pionospermrr, is derived from Guaynras.June llJlJT.I'alntr l,\7 in parl (h()l()t\pcClHlt. Greek piono (fat or plump) and spermu.r (seeded). Nonseasonalannual to small perennial herb; repro- PuruttJtas. Mpio. Sahuaripa: 1..+ nri NW ol Matarachi. ductive any time of year. Sonoran desertscrub and 28"12'05.1"N.l0ll'50'13.0"W. low hills at NW sidcof thc Matarachi vallcy, Fz,/gcr91--17q. Mpio. Y6cora: ca. f3 knt E ol Y6cora. Los thornscrub in western Sonora south to the delta region Pilarcs, Arroyo Los Pilares, 2.tJ"2l'N, 108":17'-10"W.Vtn I)tyender of the Rio Mayo; near sea level to 450+ m. Also 95-8,!6 (ARIZ. RSA): l0 rd mi NW of Y6cora on "old" rd to La southern California to Baja Califbrnia Sur, southern 'frinidad./Santa Rosa, 2U'27'.17.5"N.I 09'(X)'.17.5"W. Wi Lun 95 75. Nevada, and Arizona. Mpio. Alamos: El Rayo, ncar Chihuahua bordcr on the rd fionr The herbageand capsulesvary fiom glabrousto pu- Tayniuco to Las Chinacas, lt3 Aug 1991,Murlin s.n. (a mixed sheet bescent.The pubescentplants with Ii. unvchioides)', c.r. 5 km SSW of La Lobera on the rd to Las have ofien been segre- Chinacas. 27'15'N. 108"38'W. Sttinmann 9.1-22u. Cursu,qsua. gated as var. hirtella, but the variation in pubescence Mpio. Moris: Mcsa tie Horconcs,N of El Pilar, 19 Aug'1989,Martin shows no geographic segregation,ranges along a con- s.rr.Probably Mpio. Temosachic:along MEX 16. 30 km by rd E of tinuum from glabrous to densely pubescent,and gla- thc Scrnora./Chihuahuaborder, 28"23'49"N. I08"I9'52"W Steinmann brous to pubescent branches sometimes occur on the 1029 (RSA). same plant (e.g., Wiggins 5537, RSA). The type collection of Eupfutrbia intermixta appears EupHonera pLATyspERMaE,ngelm. ex S. Watson, Bot. to be nothing more than first-season plants, and E. in- California 2: 482(-483). 1880. Chamaesyce platy- tennixta is here treated as a synonym of E. polycarpa. sperma (Engelm. ex S. Watson) Shinners, Field & Many authors have used the presence of variable-sized Lab. 2O: 25. 1952.-TYPE: Arizona, fperhaps ac- leaves on the same plant to distinguish E. intermixtu, tually fiom Sonoral, near the mouth of Colorado but we lind this characteristic urneliable and of doubt- River, 1869, Palmer 2 (holotype GHI). ful taxonomic significance. We have observed larger Euphorbia eremit'u Jeps., Man. Fl. Pl. Calif. 600. 192-5. TYPE: leaves associated with periods of higher moisture. United States.California, Conchilla Desert [= CoachellaValleyl, Wheeler (1936, pp. 406-412) and Wiggins (1964, p. (hokttype ca. 200 ft, May 1914,Jep,wn 6017 JEPS[#2595]!). 833-835) recognized several additional varieties of E. Annual and probably facultatively short-lived peren- polycarpa, all from the Baja California Peninsula and nial with deeply buried roots; the seeds are large, and adjacent islands. Some of these (e.g., var. mejamia L. the unusual ventral ridge and curved, overhanging ra- C. Wheeler) may be worthy of continued recognition phe are unique among the seedsof subg. Chamaesyce; but are not considered here. mostly October to April. Sonoran desertscrubon dunes Euphorbia polycarpa is closely related to E. mi- in the Gran Desierto and just above the high tide zone cromera (see note under that species). at El Golfo northward to the border region in adjacent Isla San Esteban: Felger 701-1. Mpio. San Luis R. C.: Sierra del southwest Arizona; near sea level to 190 m. Also Rosario, Felger 207-10. Mpio. Guaymas: vicinity of Cafr6n del Na- northeastern Baja California and known from a single capule, Felger 85 I183A. Mpio. Huatabampo: Las Bocas. southern California collection made over 70 years ago. 26'35'30"N. 109'20'30"W Van Devender & Van Devender 92-134. VOLUME 16. NUMBER 1 Euphorbiaceae of Sonora 49

EupHoRerRpRosrRArA Aiton, Hort. Kew. 2: 139. 1189. ed States, New Mexico, between Santa Fe and Moro Anisophyllum prostratwn (Aiton) Haw., Syn. Pl. River in the mountains, 10-16 Aug 1847, Fendler Succ. 163. 1812. Chamaesyce prostrata (Aiton) 789 (lectotype MO[#20O216]1, chosen by Wheeler Small,Fl. S.E.U.S. 713, 1333.1903.-TYPE: "Nat. 1941, p. 137). of the West Indies," cultivated by Miller in England in 1758 (holotypeBM[#510671]!). Erect to ascending annual with linear leaves, the styles undivided; August-October. Known from oak Ettphorbia callitricfutide.sH. B. K., Nov. Gen. Sp.2 ffbliol: 212, and pine-oak woodland in east-central and northeast- "in Iquartol:52( 53). 1817. TYPE: M6xico. arenosismarlitinr- ern Sonora, 1050-1500 m. In adjacentChihuahua and is. . . prope portum Verlr: Crucis," 18O1. Huntboldt & Bonplurul southeastern Arizona it also grassland (holotype P, not sccn: Humboldt & BonplanclHerbarium micro- occurs in and fiche! ). the upper margin of Chihauhuan desertscrub. Also Euphorbia tenellu H. B. K.. Nor. Cien.Sp. 2 ltirliol: -12( ;13),Lquar- Baja California and California to Texas, Coahuila, and tol: 53. 1817. TYPE: Venczucla."rcsionc lcrventissimaad ri- Zacatecas. ('arichana." pas Orinoci propc Maypure'sct llt00. Hunrhoklt & The central Sonoran and adjacent Chihuahuan plants Btntplund (hol()typc P not se-ctr:Fluntboldt & Bonplantl Herbar probably iunr nricrofichel: l'r-agntcntcx B itt MO[#2]-18-51.11!). deserve infiaspecilic recognition. They pos- Charnaest'tt, lralrr'a Snrall.Fl. S.E. tJ.S.713. 1133. 19O3.Eulthrtr sess nearly smooth, brick-red to brown seeds that are ltiu rnulucu tSrnall) Littlc in JetTs& Littlc. Publ. LJniv.()klahorna very similar to those of E. gracillimo bfi quite differ- tsiol. Surv. 2: 70. 1930. TYPL,: LJnitedStatcs. Tcxas. Kerr C'o.. ent fiom E. revolutctelsewhere which regularly pos- (holorvpc Kerrville. l6(X) 2000 fi.26 30 June 189'1.Ktlltr l9l8 sesstransversely ridged, light gray to whitish seeds. NYI).

Prostrate warm-weather annual to short-lived her- \{pio. Ycicora:Arroto [:l Otro l-ado. I ] kni NNE of Y6cora on olcl rcl to Marcoba. lu l.l'-19"N. 108"5-l''ltJ"WVun l)cycndt'r 95- baceousperennial. Known from a few widely separat- ,\l(l: ca. l.l knr E ol Ydcora. Los Pilarcs. Arroyo Los Pilares, .l-l'N. ed localities in western Sonora including Sonoran des- lll lOlt.iT'-lO"W. \'rut I)<,t<'ttdcr9-5 916 (RSA)- Mpio. Agua ertscrub and tropical deciduous forest; mostly dis- Pricta: f'olonra Morclos. Agua Zrrca. lyhit( 1116 (MICIH). turbed areas,near sea level to 700 m. Probably origi- nally native to the West Indies and America, South but E,tpuoner.r srrRprrNs H. B. K., Nov. Gen. Sp. 2 [folio]: now widespread in warm regi()ns of the world. Pos- .+l(-.+2). Iquarto]: 52. l817. Anisophvllum serpen.s sibly not native in Sonclra. (H. B. K.) Klotzsch & Garcke,Abh. Konigl. Akad. Wiss. Berlin 1t359 Abh.]: 23. 1860. Mpio. Pur'rtoPcnasco: Pinlrclrtc Jrrnction IMEX 2 antl rd to l:legantc [Phys. Chamae- (-ralerl. l"el.qert(t -iJ-JIJMpio Hcrrrrosilkr:Hcrntosillo. Stcittrrttutn syceserpenr (H. B. K.) Small, Fl. S.E. U.S. 709, 577. f;lpio. Guayrnas:San Carlos. I"<,l,qtr96 -1.Mpio. Alanros: hill 1333. 1903.-TYPE: Venezuela,"in umbrosisCu- 9 mi by arr NW of Alanros ancl-l rni SSW ol PicdrasVerdcs. Sarlr/ manit prope Bordones et Punta Araya," ltl00, Hum- trs 9157. boldt & Bonplund (holotype P, not seen; Humboldt and Bonpland Herbarium microfiche!). EupHonsr.q RADIoLorDL,s Bcliss. in DC., Prodr. l5(2): 45. 1862. Chamaesyceradioloides (Boiss.) Millsp., For synonynrysee Wheeler 194I, p. 199. Field Mus. Nat. Hist., Bot. ser. 2: 4ll. 1916. Prostate nonseasonal annual, rooting at the nodes; TYPE: M6xico, [Sinaloal, Cerro de Pinal, Dec 184U, Seemann 1522 (holotype K, not seen, photo RSA!; widespread in lowland Sonora in Sonoran desertscrub, thornscrub, and tropical deciduous forest, mostly liagment F[# 19155] ll). weedy and in sandy soils; near sea level to ca. 450 m. EuJthorbiu nuliolttides Boiss. var. rabrrl Millsp.. Bull. Torr. Bot. A cosmopolitan weed, in the New World from Illinois Club. l6: 65. 1889.-TYPE: M6xico. Jalisco. ncar Guadalaiara. to California to South America. Possiblv not native in I I Dec 1888. Prin.g/t, 2066 in part (probablc holotype Fl# 1973281!). Sonora. Eupfutrbia serpens is closely related to and often Delicate prostrate to ascending warm-weather an- confused with E. albomarqinata (see note under that nual. Known in Sonora from a single collection on an species). outcrop in pine-oak fbrest on acidic, hydrothermally altered soil. South to Guerrero. An infiequently col- Mpio. San Luis R. C.: Lerdo [along the lower Rio Colorado], 1889, lected speciesthroughout its range. Palmer 951 (F). Mpio. Santa Ana: hwy about 5 mi S of Santa Ana, Wiggins & Rrtllins67 (RSA). Mpio. Guaymas: E of San Carlos, 0.5 Mpio. Onavas: Agua Maria [: Agua Amarilla], 14 Nov 1987,Mar- km NW of Estero Soldado, 15 Aug 1992. Steinrnann.s.n.Mpio. ltn s.n, Alamos: Sierra de Alamos, Aduana, 18 Aug 1992, Steinntunns.n. Mpio. Navojoa: 0.6 mi NE of turnoff to Bacobampo and 8 mi SW EupHoRerRREVoLUTA Engelm. in Torr., Botany of the of Navojoa, 26'59'N, 109'32.5'W Sanders8929 (RSA). Boundary, [in Emory, Rep. U.S. Mex. Bound.2,pt. 1l: 186. 1858. Chamaesyce revoluta (Engelm.) EupnongtR sERpyLLIFoLttlas serpillfolial Pers., Syn. Small,Fl. S.E.U.S.711, 1333. 1903.-TYPE: Unit- Pl. 2: 14. 18O6. Chamaesyce serpyllfolia (Pers.) 50 Steinmann and Felger ALISO

Small,Fl. S.E.U.S.712, 1333. 1903.-TYPE: "Hab. EupHoBerA.srrcrospoRA Engelm. in Torr., Botany of in Amer. calidiore" (possiblyat L, not seen). the Boundary, fin Emory, Rep. U.S. Mex. Bound. 2, pt. I): 188. 1858. Chamaesycestictospora (En- For synonymy see Wheeler 19,11.pp. 229 231. gelm.) Small, Fl. S.E. U.S. 714, 1334. 1903.-TYPE: Prostrate warm-weather annual with leaves charac- United States, Kansas, steep bank of the Pawnee teristically serate only towards the apex. Known from River, 8 Sep 1847, Fendler 798 (lecrorype one Sonoran collection but probably more widespread; MO[#2004821!, chosen by Millspaugh 1898, p. Chihuahuan desertscrub in northeastern Sonora. 1350 266). m, and possibly in grassland or woodland habitats. Ani.rt4tltt'llunt,rcnrft,Klotzsch & Garckc-.Abh. K<;nigl.Akad. Wiss. Widespread in North America including Arizona and Bcrlin 1859 lPhys.Abh.l: 28. 1860. TYPE: M6xico. lHidalgol. Chihuahua. Watson's (1889, p. 75) report of this spe- Los Banos Idc Atotonilco eI Grandcl. I:ltrcttlt<,rq(B. not sccn and cies from Guaymas is based on a misidentified collec- possibly dcstrovccl,photo DAV!: isotype MC). lt()t scen). tion of E. abram,siana. Annual to herbaceousperennial; mostly fbllowing Mpios. Agua Prictu/Naco boundary: Along MEX 2. l6 knr by rcl summer rains. Chihuahuan desertscrub, mesquite- ESE of Agua Prieta,3l"l(r'.15'N. 109''.1.1'.15"W.Stcitttttrurrt 918. grassland,grassland, and oak woodland in northeastern and probably north-central Sonora; 1200-1450 m. E,upuonernsERRr.rLA Engelm. in Torr., Botany of the Midwestern United States to Arizona and M6xico in- Boundary,lin Emory, Rep. U.S. Mex. Bound. 2, pt. cluding Chihuahua to Zacatecas,San Luis Potosf, and I l: 188. 1858. Chumoesrce.serrulo (Engelm.; Woot- the state of M6xiccl. on & Standl., Contr. U.S. Natl. Herb. l6: 141. Marshall Johnston's (1975. pp. 142 143) var. .sub- 1913.-TYPE: Sonora, Ior perhaps present-day laevis appearssufficiently distinct from typical E. stit.- New Mexico], GuadalupePass. on mountains(be- tospora and is probably best treated at the rank of tween San Bernardino and Sierra de las Animas), 4 species. Oct lf35l, Wright .18,1-l(lectotype MO[#144668]!, Mpio. Agua Pricta: AgLraPricta. ll Scp I9-+8../rlrr,.r r.ir. (RSA). chosenby Wheeler 19,1I, p. 24t3). Mpio. Frorttenrs:Rancho Mababi. ll nri bt rtl \\'S\\'ol I:rontcras. Prostrate summer-fall annual with large, chalky 3O':17'2.1.1"N.109'.17'-12.6"W. I"tl vcr 91 8(to. white seeds. Chihuahuan desertscrubin northeastern Er.rprroRsr.qrHyMrFoLrA L., Sp. Pl. 451. l'/53. Sonorat 1200 l3-50 m. SoutheasternArizona to west- Aniso- phyllum thvmifttlium (L.) Haw., ern Texas and Zacatecas.also in Puebla and Oaxaca. Syn. Pl. Succ. 160. 1812. Chameesyce thltmifolio (L.) Millsp., Field Mpio. Agua Prieta: 6 mi by rd S ol'Agua Pricta. 1fc1,gcr-1767. 16 Mus. Nat. Hist., Bot. ser.2: 412. 1916.-TYPE: In- knr E,SEol'Agua Pricta. ll"l(r'-1.5"N. 109"'13'.15"WSttirtrn

California to Baja California Sur, Nevada to western EupHonsre ToMENTULOSI S. Watson, Proc. Amer. Acad. Texas and Sinaloa. Arts 22: 476. 1881. Chamae.syce tomentulosa (5.

Mpio. Agua Prieta: 16.3 mi by rd N of Fronreras, Rio Moctezuma. Watson) Millsp., Field Mus. Nat. Hist., Bot. ser. 2: Felger 1008. Mpio. San Luis R. C.: Sierra del Rosario, Felger 412. 1916.-TYPE: M6xico, Northern Lower Cali- 20729. Mpio. Guaymas: Cafr6n del Nacapule, F-elger 85-1330. fornia [Baja California], Rosario, 4 May 1886, Or- Mpio. Alamos: between Rancho La Junta on Rfo Mayo and Gua, cutt l35l (holotype GH!). jariiy on Rio Guajardy, 27"35'30"N, 108'53'30"W Van Devender & Van Devender 9-l-522. Dichotomously much-branched shrub l-1.5 m tall, VOLUME 16.NUMBER I Euphorbiaceae of Sonora 5l the cyathia in dense clusters at the ends of the branch- in much need of further revision. Reference: Norton es; reproductive at various seasons. Rocky soils and 1900. slopes in Sonoran desertscrub and thornscrub; near sea l. Leaves serrateto serrulate:glands rounded; ovary and cap- level to at least 425 m. Western Sonora from Altar and sules roughened. Caborca southward to northwestern Sinaloa. islands in 2. Annual or more often perennial:ovaries and capsulespa- the Gulf of Califbrnia, and through much of the Baja pillate. the papillac rising sharply above the surface California Peninsula. . E. ultu 2' Annuall ovarics ancl citpsulcs vcrrucose. the verrucae Mpio. Pitiquito: Picr'iMts.. along ntountain top. (iatln.1.1,S.5:l2 mi gcncralfy low and broad . . . L,. .sputhulata ' E ol Puerlo Libenad. Shrevc5197. Mpio. (iuavnras:(iuitvnras. Ccrrr f Leaves entire (rarclv scrrulatc in Ll. clnntueszla): glands el Vigia. I"elgerll76l. Mpio. Navojo:r:1.2 nrj bl rd Ir o1'ME,X l5 truncatc t() bicornuatc:ovary and capsulessmooth. at I I nri by rd S of Bacahachr.ca. 2O nri N ot Sinaloa boarcler.26 3. Sterilc. dcnsc. lcafy shoots arising {iom axils of somc of Aug 196,1.Soule .s.rt. the lcavcs ol'thc prirnary stcrn (atier the initiation of flowcrs rrntlthcn nrostly along thc upper portion) or lronr thc tips of thc inllorcsccnccs . . . . L:. r'hunuu'sulu EupHonst.qrRACHysprrRMA Engelm. in Torr., Botany of .l' Stcnlc lcalv shootsIacking. the Boundary. [in Emory, Rep. U.S. Mex. Bound. -1. Annualt keels of the ovarics and capsulcs with two 2, pt. ll: 1139.1858. Chantoesy(etrachv.spenna (En- paraflel.thin rrrcnrbranousridges . . . . E. 1tt'Jtlus -1' gelm.) Millsp., Field Mus. Nat. Hist., Bot. ser. 2: I)crcnnials:keels ol thc ovaries and capsulcs lacking ridgcs. 112. 1916.-TYPE: United States,Arizona, near the 5. Longcst leaves more than 3.5 crn: both ray antl San Pedro River, 9 Sep 185l, Wright 1,3-12(holotypc cauline lcavcs lincar F,.chiribtnsi.s MOL#2004931!). 5'Longest leaves less tl.ran3.2 cnri caulinc lcavcs virriously shapeclbut rarcly lincar, ray lclrvcs not Summer annual ofien with rclbust,mostly ascending linear. and straight branches,the seedsrelatively large. Ofien (r. Cauline leavesoblanceolatc to spatulatc,attcn locally abundantin playas,low-lying flats,and savan- uatc irt thc birsc . . . . . 1:. sp. 2 nalike habitats subject to flooding in Sonoran desert- 6' C:rtrlinclcavcs linclrr.lanccolatc. ovate, elliptic- oblong to rarcly obovnte, rotrncledto attenuatc scrub and thornscrub where the plants are klcally ilt thc birsc. abundant; western Sonora liom the Pinacateregion t

above the surface, while the ovaries and capsules of Norton (see note under doubtful and excluded species) E. spathulata are merely verrucose, the vemrcae gen- differs from typical plants by possessing markedly erally being low and rounded. dentate-serrate leaves. We are uncertain if it is best treated as distinct or a synonym of the typical variety. Mpio. Cananea: Sierra de los Ajos, upper Arroyo Frijolito. N slope of Cerro de las Flores. growing below spring in anoyo bottom, Fi,rft- The Smith collection cited below possessesvery in- bein 699. Mpio. Naco: San Jos6 Mts., -5mi S of Naco. 6 Julv 1928. conspicuous serrulations on the leaf margins and ap- WoU 25 l7 (RSA\. pears intermediate between the two varieties.

EupHoRsrR BRACHYCERAEngelm. in Torr., Botany of Mpio. Nacozari: Rio Fronteras. El Tajo. White 4071. Mpio. Agua Prieta:San Luis Mts., [probably 185l]..Snrlrlr.i.n. (MO). Mpio. y6- the Boundary, [in Emory, Rep. U.S. Mex. Bound. cora: Mesa del Campanero, Arroyo Largo at the head of Barranca 2, pt. ll: 192. 1858. Tithltmalus brachycerus (En- Ef Salto. 28"20',1'1"N,109'01'30"W Steinnunn 102-1. glem.) Small, Fl. S.E. U.S. (ed. 2) 1349. 1913. TYPE: United States, New Mexico, Doia Ana, Euphorbia chiribensis V. W. Steinm. & Felger, sp. above El Paso, 1851, Wright 1821 (holotype IlO[#r4e763lt). nov.-TYPE: M6xico, Sonora, Mpio. Alamos, Sierra Saguiribo, ca. I km E of El Chiribo by the rd to Erect perennial herb; summer-fall. The two collec- Sagu:nibo, ca. 2J"17'3O'N, 108%2'W l40O m, 24 tions cited here give no habitat information, but this Aug 1993, Steinmctnn93-270 (holotype ARIZ- species is frequent in oak woodland and conifer tbrests l#3354111;'isotypes MEXU, RSA, TEX). Fig. l8-20. in extreme southeasternArizclna and presumably oc- Herba pcrcnnis erccta l6 glabri: curs in similar habitat in northeasternSonora. Also -ll crrr alta. carrlcs internodial 23 rnnr longa: firlia cauliunt sprralia.crstipulatl. llrntinaccl'f'usuc vcl New Mexico, Texas, and Chihuahua. Mearn's collec- valde dcflcxac, linacrcs vcl ar)gustclanccolato-cllipticae. integrac. tion from the San Luis Mountains is fiom the Chihua- basi attcnultae. apicc ucutuc.pctioli ca. I rrrnr krngi vcl nulli: unr hua-Sonora border and could be fiom either state. bclla 3 radiata. radiis l.tl 7.6 cnr longis. I .1 bitidisr firlia basalia Euphorbia brachycera is closely related tct E. cha- inflorcscentiaeternata: tirlia ratliorunropposit:r Iincaria. elliptica vel angustc hnceolata, acutu, subsessilil: pc.dunculi maesula. The two can be difficult to distinguish from 0.6 1..3ntrn litngi; involucra late obconica, 1.3 2.1 nrnr longa. l.O 1.0 rrrnrdianrctro. each other, and their relationship is indeed puzzling. internc pubcsccntia;glandulac 4, sernicircularesvcl lcvrter lunilres. In general, E. brachr*cera lacks dense sterile branches 0.3 0.(r mrn longae (tangentialitcr).0.7-l.l ntnt latae (radialiter), arising fiom the leaf axils of the primary stems, lacks rrrargoglantluluc integer vel levitcr sinuatus,cornua nulla vcl usque Ieaves that are appressed upwards to the stem, has a ad 0. 15 mm longa; flores d ca. l0 l-5; ovariurn 3-lobatum; styli 3, 0.8 1.0 mnr longi. connati looser inflorescence, and possessesslightly smaller ad basint, bifidi: capsula subglobosa, 3 lobata.2.U .1.0mnt longa, 3.3 3.9 mni diantetro:scntirra ovoidc

lmm

1cm lr**

?.c-k-111

Fig. 18-20. Euphorbia chiribensis. 18. Habit. 19. Cyathium.-20. Seed. All from Steinmonn 9-l-270.

slightly smaller; ray leaves opposite, subsessile,their opposite ray leaves, the peduncles 0.6-1.3 mm long; blades linear, elliptic, to narrowly lanceolate, 7-16 mm involucres broadly obconic, 1.3-2.I mm long, 1.0-2.0 long, 1.5-4.0 mm wide, apex and base as in the cau- mm wide just below the glands, glabrous on the out- line leaves;rays of the umbel 3,2.8*7.6 crr'long,24 side, pubescent within, the lobes rounded, ciliate, to times bifurcating with cyathia borne in the axils of the ca. 0.5 mm long, the sinus shallow; glands 4, yellow- 54 Steinmann and Felger ALISO green to red-brown, slightly crescent-shapedto semi- rope, Linnaean Herbarium 630: 24. (.syntypeLINN, circular, 0.3-0.6 mm long (tangential axis), 0.7-1.1 not seen, Linnaean Herbarium microfiche!): Hort. mrn wide (radial axis), the distal margin smooth to Cliff. 16 (BM syntype, not seen). slightly sinuate, the lateral sides sometimes possessing Spring annual, noteworthy in possessingovaries and hornlike projections to ca. 0. l5 mm long, appendages capsules with two thin, parallel membranous ridges absent; bracteoles ca. 4 per involucre, included, fili- along the keels. Known in Sonora from a single col- form and with a few hairlike divisions at the apex; d lection made in March fiom a yard at San Bernardo; flowers ca. l0-15, androphores glabrous; gynophore 200 m. It is expected elsewhere around habitations glabrous, reflexed and emerging through the sinus dur- throughout the state. Native to Eurclpe and eastern ing maturation of the ovary, erect and extending to ca. Asia, now nearly wclrldwide. 3.0 mm long in fruit; ovary roundly 3-lobed; styles 3, 0.8-1.0 mm long, connateat the base to ca.7u their Mpio. Alarnos: San Bcrnarclo.Steiturtunn 581. length, free above. bilid ca. 1/zt<> 2/t their length, the tips slightly dilated; capsule subglobose, distinctly Eupuonere spATFrL.rr-ATALam., Encycl. 2: 428. l'/88. 3-lobed, 2.8-4.0 mm long, 3.3 3.9 mm in diameter; Tithymalus spathulatus (Lam.) W. A. Weber, Phy- seedscrvoid-oblong, 2.0-2.5 mm long, 1.1 1.9 mm in tologia 58: 384. 1985.-TYPE: Brazil, near Mon- diameter, dull griry black. alveolate, rounded to trun- tevideo, Commerson (holotype P, not seen, photo cate at the base, obliquely angled at the apex, with a RSA!). well-marked adaxial line and a cream colored. hood- L,uJtlutrbiudictt'tlsptrnut Fisch. & f'. A. Mcy.. Intl. Sern. Hort. Pc shapedcaruncle 0.6 mm long, 0.4 0.5 mm wide. 'l trop. 2: 37. ltt.16. itltynultts dit ttttspcnnus (Fisch. & C. A. Known

Eupnonerl pEpLUSL., Sp. Pl. 456. 1753. Tithymalus EueHonernsp. 2 peplus (L.) Hill, Hort. Kew. 172. 1768. Esula peplus (L.) Haw., Syn. Pl. Succ. 158. 18l2.-TYPE: Eu- Weak-stemmedperennial herb to ca. O.4m tall;Feb- VOLUME 16.NUMBER I Euphorbiaceae of Sonora 55 ruary-April. Understory of pine-oak woodland; 1300- stated that the type was Thurber 265 at GH. This 1580 m. Documented in Sonora from only two local- specimen bears the label "Sta Cruz, Sonora, Mexi- ities. Otherwise known from adjacent southwestern co, ?Sept. 1851." The "265" was added later and Chihuahua, with many collections fiom the Basaseach- refers to the number given by Boissier (1862, p. 73) ic area. to this species. According to Mark Maytield (pers. Apparently this is an undescribed species related to comm., 1996) and Wolf (1988) the only original ma- EuJthrtrbia brttchycera and possibly also to Euphorbin terial in Engelmann's herbarium is Smith's specimen campestrisCham. & Schltdl. The relationshipsamong (also numbercd 265) from Agua Zarco.lt is unlikely speciesin this complex are enigmatic and in need of that Engelmann ever saw the Thurber specimen at critical study. GH, and possibly he was aware of this collection's existence only through communicaticlnwith one of Mpio. Alirmos: Sicrra Saguaribo. Blrrrunca Huicochic. ca. his contemporaries. Therefore, Dressler's designa- 27"18'30"N. 108'39'30"W. StcirttnurtttJliJ. N{pio. Ycicora:Cicrnaga dc' Camilo. 6.3 knr E of El Kipor. I l.l knr W of the-Chihuahua tion of this specimen as the type (i.e., lectotype) bordcr. 2U".13'05"N. IOlt -l-l'0-5"\\'. \'tut I)tt,tnt!cr 971()1. should be considered invalid. The Smith collection at MO (ex herb. Engelmann) is the only one that we are aware of suitable to serve as lectotype. SubgenusPoirtsettirt (Graham) House l: Poin,settiu Grahan'rl I'.ultlrtrbiu tubcrostt Rosc. Clontr.U.S. Natl. llerb. l: lll. 189ll not Ii. tubcrostrL.. l7-5-1. TYPF,: Mdxico. Sonora. Alamosl, Annuals to perennial herbs (in ours), or with E. pul- IMpio. Sierra de Alarrtos, 2-5 Mar lJ Apr llJ90. I'alnt<'r -15(t(holotvpc cherrima Willd. ex Kkrtzsch a shrub or small tree. Lrs[#4779rJlr). Cauline leaves alternate or less fiequently opposite. lacking conspicuousstipules; subcyathial leavespseu- Contro hierba. Elegant perennial herb with linear dowhorled and ofien infused with white to red pig- leaves, those subtending the cyathia with bright red ments. Glands cuplike or bilabiate,usually l-3 per bases, involucres and capsules also partly bright red; grassland cyathium; appendagesabsent. Seeds ecarunculate()r March-October. Oak to pine fbrest in eastern not. Sonora; U00 1600 m. Also Chihuahua, Sinaloa, Du- New World; ca. 20 species.the centerof diversity rang().and Zacatecas. in M6xico where about l3 species()ccur; seven species The Santa Cruz collection made by Thurber is pre- in Sonora.The commonly cultivatedChristmas Poin- sumably fiom the town on the Rio Santa Cruz, in the present-day Municipio de Santa Cruz, and Smith's settia is E. ltttlclterrirrrr. Rel-erence:Dressler 1961. "Agua Znrco" is probably Agua Zarca south of Co- l. Attnulls: reproductircJulr to Dcccrrrbcr.rarell orcrsinlcr- lonia Morelos in the present-dayMunicipio de Agua in8. 2- Ovarics antl capsrtlcspubcscent l'.. t ultltrt.tlx'rtrtu Prieta. Both these collections are close to the Arizona 2' Ovaries antl capsrrlcsglabrous. border, howevel this species is not known fiom Ari- .1. Cilandscylindric, thc opcning circulrr I:. ltrttnrph.tlkt zona, and such a showy plant is unlikely to be over- J' Clands bilabiatc, thc opcning oblong. looked. .1. Srrbcyathiallcaves red to pink at thc b:rsc (olicn tucling and tlil'licult to distinguish in tlrl rpcci Mpio, Huachineras:Pie-dra Parada. W/rrla -161(t. Mpio. Yercora:21.3 rrrcns).cirrrrnclc abscr)t or rrrinutcanrl nunclilirrnr krn W ol'Maycoba on MEX 16. 28"23'35"N. 108";17'W.Van De . I'.. t'tulholtlutnt vt,ruler 95 -i-5,3.Mpio. Alamos: Sicrra clc Alanros. Wicns 9.1-157 'll'popa. -1' Subcyathialleavcs grccn ilt thc bascictntnclc con (lentrv 2229. sll ieuorts. r!'n i I' ,nI I:. luvidii l' Perennialherbs fionr tubers:variously reproductivcthrough EupsonetR cupHospeRMn(Englem.) Boiss. in DC., out thc ycar. often in tl.respring. l5(2): 1862. Euphorbia 5. Subcyathial le'avcswhite to light pink. sontctirtre-slc. Prodr. 73. dentata Michx. duced ....l,.nuliuns var. [as rf cuphosperma Engelm. in Torr., Botany of 5' Subcyathial lcavcs intensc rcd. at lcast at the basc. the Boundary, [in Emory, Rep. U.S. Mex. Bound. 6. Subcyathial leaves lincar. the margins cntirc: stcnrs 2, pt. ll: 190. 1858. Poinsettia cuphosperma (En- glabrous I:. cttlttnttut gelm.) Small, Fl. S.E. U.S.72l(-722), 1334. 1903. 6' Subcyiithial leaf-shapevarious but rarely linear, the Euphctrbia dentata Michx. fbrma cuphosperma (En- nrargins serratcl stems pubescent I'). strig.ostt gelm.) Fernald, Rhodora 50: 148. 1948.-TYPE: United States, New Mexico, Copper Mines EupHoRsra coLoRArA Engelm. in Torr., Botany of the [near Bayard, ca. 25 km E of Silver Cityl, 1851-1852, Boundary, [in Emory, Rep. U.S. Mex. Bound. 2, pt. Wright 1834 (lectotype MO, not seen, designated by 1l: 190(-191). 1858. Poinsettia coloratd (Engelm.) Wolf 1988,p. 1626). Dressler, Ann. Missouri Bot. Gard. 48: 336. 1962.- TYPE: The protologue states "Dry arroyas[sic], Annual with predominantly opposite leaves, the Agua Zarco, Sonora, May; and Santa Cruz, Sept.; ovaries and capsules pubescent; August-October. Thurber, & Capt. E.K. Smith." ln 1961 Dressler Pine-oak woodland in northeastern and east-central Steinmann and Felger ALISO

Sonora; 1600-1900 m. Southeastern Arizona and 1890.-TYPE: United States, Arizona, Bowie, I Sep 188,1,-/onas southwestern New Mexico to Coahuila and Oaxaca. .r.rr.(holotype Il not seen;isotype POMI#854891!). (196I, Dressler pp. 338-339) treated this and a Leafy erect to ascending summer-fall annual. Grass- number of other species as synonyms of an inclusive land to oak and pine-oak woodland in southeastern E. dentata Michx. However, according to Mark May- Arizona, and presumably similar habitat in northeast- (pers. field comm., 1996), who is preparing a revision ern Sonora where it is known from a single collection of the subgenus Poinsettia, there are five North Amer- that does not give habitat information. ican species within the E. dentala complex. We follow This species, a member of the Euphorbia dentata his suggestion to recognize E. cuphospermrz as dis- compfex, is very similar to E. cuphosperma but can tinct. be distinguishedby the glabrous ovaries and capsules and the larger reniform (vs. Mpio. Santa Cruz: microwave towcr above Pucrto Cananea.Sicrra smaller and punctiform) Cananeacii.9 rni W of Cananeaon MEX 2,Vtm [)et'entlergO 5t2. caruncle. Originally ranging from the Great Lakes re- Sleinmann 94.5. Mpio. Y6cora: Arroyo El Kfpor (Qufpor). .just E of gion through the Great Plains to southeasternArizona, El Kfpor on trail to Ticrra Panda (Las Taunas),28"2,1'N. Sonora, Chihuahua, and Coahuila; introduced among 108"33'35"W. Van [)a'ender 9-5 910. other places into the easternUnited States,California, and Argentina (Mark Mayfield, pers. comm., 1996). EtrpHongre cyATHopH()RA Murray, Commentat. Soc. Regiae Sci. Gott. Recent. 7: Ul; tab. l. 1786. Tith,-- Mpio.Agua Pricta: C'abullona. Aug 1917..1tnt.:.s.rr. (SD). malus cyttthophorus (Murray) Moench, Methodus .1-53. 667. 1794. Poinsettia cyothq)hore (Murray) Klotzsch EupHonerrHErcRopHyLLA L.. Sp. Pl. l'153.Titht-- & Garcke, Monatsber. Krinigl. Preuss.Akad. Wiss. malus heteroph,-llu.r(L.) Haw., Syn. Pl. Succ. 1.1l. Berlin 1859: 2-53. 1859. Eulthrtrbia heteroTthvllaL. 1812. Cl,athophoruhetentythvllu (L.) Raf., Fl. Tellur. v'ar. c'vathopfutra (Murray) Boiss. in DC., Prodr. 4: 11"7.1tl3U. Polrr.settiu hetentlthylla (L.) Klotzsch 15(2): 72. 1862. Euphorbio heterophvlla L. fbrma & Garcke, Monatsber. K(inigl. Preuss.Akad. Wiss. c1-athophora (Murray) Voss, Vilm. Blumengdrtn. Berlin 1859:253. 1859. TYPE: Tab. I12, fig. 6 in (ed. 3) l: 898. 189-5.-TYPE: Based on cultivated Plukenet, Phytographia. 169l; text on page 369 of material grown at the GcittingenGarden, the origin Almagestum Bcltanicum. I 696. of the seedswas unknown to Murray. In the absence Forsynonynry scc Drcssler 1961, pp. 339 340. of a specimen, the illustration in the protologue serves as type. Annual with highly variable leaves (see ^8. cyatho- phora); August November. Grassland,oak woodland, For synonynrv sec Drcssler 1961, p. 33t3, tropical deciduous forest, and occasionally washes in Summer-fall annual, rarely overwintering, the sub- Sonoran desertscrub;24O 1600 m. Easternand central cyathial leaves with red to pink bases.Oak grassland, Sonora. Southeastern Arizona. to extreme southern thornscrub, and tropical deciduous forest; 24O l4O0 Texas and south Florida to South America: naturalized m. Eastern Sonora from the vicinity of Imuris and the in the Old World. Plants with predominantly linear Rfo de Bavispe region southward. Also eastern United leaves have been treated as var. graminifolia Engelm., States to New Mexico, widespread in M6xico, the but leaf variation in this speciesis not of taxonomic value, pointed (1961, West Indies and South America; naturalizedin the Old and as out by Dressler p. 338), World. ,tO. of this variety is a specimen of E. cltathopho- Resembfing and often confused with E. heterophyl- ::: /a; both show considerable variation in leaf size and Mpio. Baccrac (or pcrhaps Huachincras):Horconcitos. Whitc ,\-15. shape, even on the same plant. Mpio. Hcrmosillo: l6 mi S of Hermosillo on rd to La Palrna.lli,q- gin.s & Rollins i 9,3. Mpio. Alarnos: San Bcrnardo, Gentrt l67.l. Mpio. Cucurpe: Magdalcna Canyon, 9 mi NE of Imuris. .S/rrt,r'r, 66 17. Mpio. Bavispe: Cafr6n de la Bellota. Sierra de la Caballera. EupHonsrn RADTANSBenth.. Pl. Hartw. 8. 1839. Poin- White 1685. Mpio. San Pedro de la Cueva: mounrainsideN of pass (Benth.) in Sierra de Batuc, between Miitapc and Batuc, Wg3lns & killins settia radians Klotzsch & Garcke, Monats- 411. Mpio. Alamos: Anoyo Mentidero at El Chinal Rd. I1.3 km S ber. K

Mpio. Alamos: ca. 3 kn by rd W of Las Chinacas, along rd to J,crnopHa cARDropHyLLA(Torr.) Miill. Arg. in DC., Taymuco, 27'l,t'45"N, I0u'4l' I5"W Sleinnrunrt9,1--ll: Saguaribo Prodr. l5(2): 1019. 1866. Mozinna cardiophylla to Curogui, l8 Mar 1992, Yettnun .s.rt. Torr., Botany of the Boundary, [in Emory, Rep. U.S. Mex. Bound. 2, pt. 1l: 198. 1858.-TYPE: Near JATROPHA L. Tucson and Sierra Verde. Sonora. 1855. Schott s.n. (holotype NY!). Trees, shrubs, perennial herbs, or rarely (not ours) annuals, the stems usually flexible; monoecious or dio- Sangrengado. Caespitose shrub with numerous ecious. Latex clear or colored but not milky, bleeding spreading flexible stems mostly ca. 1 m tall (occasion- profusely when cut. Pubescence absent, unbranched, ally to 2* m east of Hermosillo) arising from the base, or glandular. Leaves alternate, frequently crowded and the petals white. Small leaves are put out shortly be- fasciculate on short shoots. blades often lobed. entire fore the sunrner rains, and plants are leafy only during 58 Steinmannand Felger ALISO the summer rainy season; reproductive in early sum- Loureiru glondulosa Cav., Icon. -5: 18; tab. 43O. 1199. A nomen mer. Sonoran desertscrub, mesquite-grassland, thorn- superfluum listing thc earlier Mo:inrn cortlata in synonymy. scrub, and lower margins of tropical deciduous forestl Miguelito, torote papelil/o. Shrub or narrow tree to 50-900 m. Widespread in arid areas of Sonora but not ca. l0 m tall with exfoliating, papery bark, the leaves west of MEX 8 in the northwestern part of the state. presentonly during the summer rainy season,the flow- Also southern Arizona. ers pink or sometimeswhite; June August(-October). Sonoran desertscrub,thornscrub. and tropical decidu- Mpio. Trincheras:Cerro Quelitosa,Trincheras. Rntv.n 81-11. |y'rpt<:. Arizpe: Arizpe,'l-urncr /9-5. Mpio. Bavispc: Cafr6n dc las Belloras. ous forest. Sonora northward to the Sierra el Aguaje White -l57ll (RSA). Mpio. Guaynras:Sierra Libre. 0.3 mi E of MEX near the coast, and inland northward to the vicinity of l5 on rd to Microontlas Avrspas. Fel.qerE5 /1),92.Mpio. Alarnos: Magdalena and the Rio de Bavispe region; near sea N of Alanros. near Tcpistate, Gcntrt 1,\-l(t. Mpio. Navo.j()a:Irrancisco level to 900 m. Also southwesternChihuahua south to I. Madcro, ca. 26 krrr SSE o1-Navoiouon MEX lr5. Stcirtnttttttt9-l -r,92. Jalisco andZ'dcatecas.Hinton 1485 (MICH). fiom Te- mescaltepec,Estado de M6xico, also appearsto belong to this species. Jarnopu,r crNERrrA(Ortega) Miill. Arg. in DC., Prodr. l5(2): 1078(-1079).1866. Moz.innd cinerea Ortega, Mpio. Alarrr

5-lobed) with deeper divisions, narrower lobes, and portion; petals 0; stamens usually 10, in two unequal more sharply incised margins. The two varieties are series of 5 longer and 5 shorter free filaments. Pistillate geographically disjunct with var. macrorhiza occurring flowers with a petaloid calyx of five sepals united only in Aguascalientes and Zacatecas. at or near the base; petals 0; ovary 3-locular, with I ovule per locule; styles 3, short, united at the base, Mpio. Bavispe: betwecn Santa Rosa Canl'on and Bavispe, Wlritc branches broadly dilated and multilobed. Fruits cap- 62-1.Mpio. Bacoachi: l7.tl mi by rd N of Bacoachi.S[: of Ccrrc la Cicneguita. l.'i.rhbein I 260. sular. Seeds carunculate. New World in tropical and subtropical areas,ca. 100 JarRopu,qMAr-ACopHyLLA Standl.. Proc. Biol. Soc. Wash. species; ca. 2O speciesin M6xico and live in Sonora. 37: 45(-46). 1921.-TYPE: M6xico, Sinaloa, Mpio. The Cassava,Manihot e.sculentaCrantz, is widely cul- Mazatl'in, El Zapote, 1923. Ortegu 5208 (holcxype tivated in tropical areas fbr its edible tuberous root. us[#r11r3201!). Ref-erence:Rogers and Appan 1973. l. Largcr lcat lobcs with a tornlinul. hairlikc bristlc rnorc than .luln;phu Standl.. Ficlcl. Mus. Nat. Hist.. tsot. scr. l2: ltlatunilitliu (2 )-5ntnt long. 18. l9:10. TYPE: !IIrico. Sonora. Alarnosl. San tscr lMpio. L Lcaf krbcs linclir to lincar-oblone(rarcly lincar obovatc). nard

MANIHOT Adans. Mpio. Alanros: ca. 7 km by air ESE of Alamos. 26"59''+5"N. 108"52'W.Steinnutnn 94--59: Ctiirocoba crossingof the Rio Cuchu Trees, shrubs, large herbaceous perennials or rarely jaqui, 12.3 km by air SSE of Alanros. Aug 1992. Me.t'er.s.s.n. clambering vines, the roots often tuberous; monoe- cious. Milky latex usually present. Pubescence un- MeNrHor ANGUSTTLoBA(Ton) Miill. Arg. in DC., branched or absent. Leaves alternate, usually (as in Prodr. l5(2)i 1073(-1014). 1866. Janipha manihot ours) long-petiolate and deeply palmately lobed. Inflo- H. B. K. var. angustiloba Torr., Botany of the rescencesusually bisexual, terminal or pseudoaxillary, Boundary, [in Emory, Rep. U.S. Mex. Bound.2,pt. racemose or paniculate, mostly with proximal I flow- 1l: 199. 1858.-TYPE: Three collections are cited ers and distal d flowers. Staminate flowers with a pet- in the protologue, including the following: Sonora, aloid S-lobed calyx that is usually united in the lower Sierra W de Sta. Cruz v Tubac. 1855. Schot lTubac 60 Steinmann and Felger ALISO

is along the Santa Cruz River in Arizona; this lo- collection or belongs to a separatetaxon. Unfortunate- cation was included in the Gadsden Purchase, so the ly, flowers are lacking. type may have been collected in present-day Ari- Mpio. Bavispe: Santa Rosa zona.l. According to Rogers and Appan (1973, p. Canyon near Bavispe, White 512. Near boundaries of Mpios. Guaymas and Hermosillo: 5 n.ri E of main 57), Torrey's variety was based on two different spe- hwy between La Palma and Cienequita. Wiggins & Rollin.s 221. cies, with one of the syntypes (Nuevo Le6n, near Mpio. Cucurpe: Palm Canyon, SE,of Magdalena, l6-17 July 1977, Monterrey, Gregg) not belonging to the commonly Van Devender et dl. s.n. Mpio. Alarnos: Mesa Masiaca along the rd interpreted circumscription of M. angustiloba. Cro- to mlcrowave towcr, 6.5 krn by air NNW of San Jos6 de Masiaca, 2.5 km NE of MEX 15. Vurt [)eyender izat (1942, p. 224) stated rhat the Schott collecrion & Vun Dt'yentler 92-1t08. at NY |l was the "holotype" and annotated the M,q,NtHor RUBRTcAULTsI. M. Johnst., specimen as such. Rogers and Appan (1913, p. 57) Contr. Gray Herb. 68: 90. 1923.-TYPE: M6xico, Durango, near Du- rejected the holotype status of this specimen, but by rango City, E slope of Iron Mt., 1896, not designating a lectotype and instead "designating Paltner 224 (There are two sheetsof this collection ar syntypes," they did little to clarify the situation. GH [!], both of which were identilied as "type" by I. Croizat's associationof the Schott specimenas "ho- M. Jcrhnston.McVaugh in 1994 annotated the sheet la- lotype," although semantically incorrect under cur- beled "l" as the lectotype). rent usage of the word, indicates his intention fitr it to serve as the nomenclaturaltype. Thus, we attrib- Munilrtt i,rolobrrStantil.. Fielci Mus. Nat. Hist.. Bot. scr. l'l: l9i. ute to him the lectotypificationof M. ungustiloboby 193-7.Munihot rultrituulis L M..lohnst. ss1.r.r.rolobrr (Standl.)D. the Schott specimen. J. Rogers & Apparr. Fl. Neotrop. Monogr. l3: .1(r.1971. TYPL,: M6xico, ChihuahLra.Ciuasarcnros. skrpcs. l0 Aus l9J(r. (irnlrr. Herbaceous perennial or subshrub; July October. 2-l22 (holotypc Fl#86.1511I ll). Sclnoran desertscrub, thornscrub, tropical deciduous Pata de ,qa1lo.Shrub to -5 m tall. the leaves often fbrest, grassland, and oak woodland; 30 1200 m. ashy blue-green and glaucous. leaf lobes usually slen- North-central Sonora southward at least to Sinaloa. der and with a soft bristle-tip; June-October.Tropical Also southern Arizona, Chihuahua, and Baia Califbr- deciduousforest, oak woodland, and the upper margin nia Sur. of Sonoran desertscrub. Eastern Sonora ficlm Arizpe Specimens fiom coastal areas of Sclnclraand nclrth- and Magdalena Palm Canyon scluthward and eastwardl western Sinaloa often have notably broad leaf lobes 900-15-50 m. Also Chihuahua, Sinaloa, Duranso, and with entire margins or broad, shallow secondarylobes. Nayarit. In contrast, specimensfrom inland Sonora as well as The subspeciesas defined by Rogers and Appan Arizona and western Chihuahua have slender leaf (1913, p. 46) do not seem distinguishable.These au- lobes with narrow, attenuate secondary lobes. The sig- thors separatedthe two by the narrctwer leaf lobes and nificance of these differences is not apparent. smafler fiuits and seeds of ssp. rubrit'tur1l.r, referring only two collections to this subspecies. Mpio. Trinchcras:bajada S of Las'Iiinchcras. Shreve 6-t71. Mpi

MRNtsor DAVTsTAECroizat. J. Arnold Arbor. 23: Mpio. Cucurpc: Palnr Canyon, (lcno Cinta de Plata, l6-17 Julv 224(-225). 1942.-TYPE: United States, Arizona, l9'7'7,Van l)evender & Miksicek.r.r. Mpio. Bavispc: Cafr6ndc Bav Santa Catalina Mts., 27 Aug 1883, Lemmon s.n. (ho- ispe. White -ll0-1:21 mi E of Nuri, Goldberg & Wurrert 76 209. Mpio. Alamos: 5.1 mi NE of El Taymuco. Burge,s.s-594.1: Baka- lotype U5[#62129]l). chaka. hill slopcs. (ierrtrr 1168: E slopesol'Sierla de Alantos, Sau- cito Canyon, Van l)eventler 9-l-l-l-14. Shrub l-2.5 m tall; July-October. Thornscrub, up- per margins of Sonoran desertscrub, and lower mar- MeNtuor sp. gins of oak woodland in north-central, eastern, and southern Sonora; 100-1200 m. Southeastern Arizona Shrub or small tree 5-6 m tall with a thick Bursera- to Sinaloa. like trunk and red, exfoliating, papery bark; leaves gla- Rogers and Appan (1913, p. 53) recorded this spe- brous to moderately pubescent, the bases often sub- cies for Chihuahua, based on Gentry 2450 from Sa- peltate, the leaf lobes 7 or 9, obovate, entire, the apex wakoa. This specimen lacks secondary leaf lobes and rounded to truncate or emarginate and with a hairlike in this feature differs from other collections of M. dav- bristle 5-18 mm long; seedsto 13.5 mm long; July- isiae. We are unsure whether it is simply an anomalous September. Central-eastern and southeasternSonora in VOLUME 16.NUMBER I Euphorbiaceae of Sonora 6t tropical deciduous forest, 2OO-160 m; also southwest- l. Latex yellow; leaves4.5 10i cm longl fruits dehiscent,glo- ern Chihuahua. It is especially common on some bose, and not spurred at the base . . . . . P. bracteatus I Latex white: leaves to about 1 cm longl tiuits indehiscent, mountainsides, canyon slopes, and slopes above the angled. and spurred at the base . . . . . P. macntcorpus Rio Mayo between Mesa Colorado and Chorijoa. The identity of this unusual manihot is unresolved, Pp,otlRNrnusBRACTEATUs (Jacq.) Boiss. in DC., Prodr. due in part to a paucity of specimens with flowers and l5(2): 6. 1862. Euphorbia bracteata Jacq.,Pl. Hort. fruits. It does not fit any of the six species of truly Schoenbr. 3: 14, pl. 276. 1798.-TYPE: Based on arborescent manihots known from M6xico, all of material growing in the Schdnbrunn Garden near Vi- which were placed in section Foetidae as proposed by enna; its native land and collectors were unknown Rogers and Appan (.1913). It appears to be the same to Jacquin. The type is the plate in the protologue. entity as Palmer 201 (GHl) which was collected at Hacienda San Miguel near Batopilas, Chihuahua, in f'edilanthu.s rub<'sctns Brandegec. Zoc 5: 209. 1905..*TYPE: M6x- September of 1885. This collection is a syntype of ico, Sinaloa, Culiacin, l2 Oct 190,1,Brandtgee .r.n. (holotype Manihot caudata Greenm.. but we are not convinced LJC[#| l0 tsr]l!). that it represents the same taxon as the other syntype: For additional synonymy scc Drcssler l9-57,pp. 125 126. Michoaciin, Monte Le(rn, volcanic hills, 2l Aug 1902, Pringle 8682 (GH!). The leavesof plants in Chihuahua Candelilla. Shrubby, much-branched, stem-succu- and Sonora possessseven or nine lobes, while those lent to 2.5 m tall with large, drought-deciduousleaves, (1957, of plants fiom Zacatecas,Jalisco, Guanajuato, and Mi- the involucral glands reported by Dressler p. (3 choacdn possess5 lobes. The lack of flowering spec- 126) as 2 or 4); for Sonora recorded in flower May, imens fiom Chihuahua and Sonora prevents a more October, and December. Uncommon in the tropical de- complete comparison. We are unaware a lectotypifi- ciduous forest and oak woodland of southeastern So- cation for M. caudata, and to best conform to current nora. 300-600 m. South to Oaxaca. usage we designateas lectotype the Pringle collection Mpio. Alamos: Cianyon llstrclla. in thc undergrowtl.r,Gsrtrr' .1,3-5.5 from Michoacdn. The taxonomic disposition of the rrri Nts ol Alalnos, Jenkin.s9llil: rd front Alarnos NIt to Cuchu plants in Sonora and Chihuahua will have to await the huari.29 Dec I99 l. Murtin & ()'Rourkt.s.n. procurement of m

and of deciduous axes with distichous phyllotaxy often only three collections, the one from Sonora and two floriferous. Latex absent. Pubescence usually un- others from Michoaciin. branched or absent. Leaves (in ours) alternate, often Mpio. Alamos: ca. 1 km by air E,SE of Alamos. 26"59'45"N, distichous, entire, penniveined. Inflorescences usually 108'52'W. Steinnumn 9140. axillary (or the flowers solitary in the leaf axils), fas- ciculiform cymes. Staminateflowers usually with 4-6 *Puyr-lnurHLrs MocrNrANrrsBaill.. Adansonia 1: sepals; petals 0, stamens mostly 2 6, the filaments free 35(-36). 1860. TYPE: Some unknown location in or connate.Pistillate flowers with 5 or 6 sepals;petals M6xico, Ses,sd& Mog'iiio (holotype "h. Less." [De- 0; ovary usually 3-loculal with 2 ovules per locule; lessert'sherbarium now at G-DELI, not seen). styles usually 3, free or united, variously divided. Fruits usually capsular(ours), sometimesfleshy. Seeds Bushy, spreading, luxuriant shrub to ca. 2 m tall; ecarunculate. probably reproductiveJune to September.Documented A large and diverse genusof trees.shrubs, and herbs fbr adjacent southwestern Chihuahua and possibly containing approximately 750 speciesin about 50 sec- present in the tropical deciduous fbrest or ktwer oak tions. The speciesare almost exclusively tropical with woodland of southeasternSonora. SouthwesternChi- the majority in the Old World. About -50 species in huahuato Central America. M6xico. Ref-erence:Webster 1970. This species is ofien confused with Phltllanthus mi- crandu.r MiJll. Arg., but according to Grady Webster L Shrub; Ieavcsbrolrdlv ()\'ateto ncarlv orbicular.ntore than l (pers. clrttvitlc ....;'.rttrttittirutt.t,; c

portion and d flowers in the upper portion. Staminate Petioleseglandular . S. ltttt,onrctnu flowers with a 3-5-lobed calyx; petals 0; stamens nu- Adaxial side of the petioles bcaring conspicuous.annular, flat to patellifornt glands just below the base of the merous, the filaments much branched and bearing nu- blade. 2. Leavcs usually ntorc than 3 cnt wide. the petioles 2 or merous (up to ca. 1000) anthers.Pistillate flowers with morc cm long: glands absent from leaf margins: ovary 5 sepals; petals 0; ovary usually echinate, 3-locular, 3-celledwith 3 styles . S. d,rnutat with I ovule per locule; styles 3, free or connateat the 2' l-cavcs(in ours)lcss than 1.5( 2.5) cnt widc. the petiolcs base. bipartite, papillose-plumose. Fruit capsular. lcss than I cm long: glands ottcn presentalong leaf ntar Seedscarunculate. gins: ovary r.nostly2 celleclu'ith 2 styles .. S. biloculari.s Monotypic; native to northeasttropical Africa (Rad- cliff-e-Smith 1987, p. 322). Widely cultivated and now SEe,ASTreNrA BILOCLTLARTsS. Watson. Proc. Amer. naturalizedthroughout much of the tropics. The seeds Acad. Arts 2O: 314. 1885. Srzplum biktculare (5. are the source of Castor Oil. fbr which there are many Watson) Pax, in Das Pflanzenreich IY. 141. v [Heft medicinal and industrial uses. 521:.221. 1912.-TYPE: M6xico, Sonora, by water- coursesnorthwestern mountains,2'l Mar 1884,Prin- RrcrNrrsco\{N.rrr\rs L., Sp. Pl. 1007. l7-53.-TYPE: gle s.n. (lectotype GHl, here designated).Another Sheet .1-50.Rit'inus I from the Herbarium of Hor- specimen is cited in the protologue: Sonora, hills tus cliffortianus (lectotype Idesignatedby Seege- between Rayrin and Ures, Oct 1851. Thurher 901; ler l9tt3. p. 2l2l BM, not seen, photocopy we were unable to find a specimen at GH, but there RSAI). is a specimenat NY [!].

More thlrn 5O spccics (scc firzlr,r r(<,rr.r,l.rl.r)unrl Itrrie-tics harc bccn Sttpiurrtltiltx'uLll'('(S. Wats()n)Pax var'.tunltlutn I. M. Johnst..Proc. proposerl. but t)lost rcccllt ruth()rs 'I'YPE: trcat thcsc within lr ill()n()l\t)iu Calrl. Acad. Sci. scr lY. 12.:l(l-71 . 1921. Mixico. B:rjl Rici tt i.s torrtntun i.s. Crrlitirrnia lSurl. l-orcto. fr-cclucnton sandy plain back ol' town. f 9 Mirr' 1921 (holotypc Higuerilla, Castor Bean. Large arnnualto shrub, oc- ..loltrt.:ttttt.17l2 CASI#ltll58l!). casionally a small tree; reproductive alm()st any timc Hierba de lu _flechrtMany-stemmed shrub to rarely of year. Occasional in Sonoran desertscrub but fie- treelike and 6 m tall; reproductive more or less quent in thornscrub and tropical deciduous forest throughor,rtthe ycar. Sonoran desertscrub,less ofien in where it is sometirnescultir,'ated and ofien weedy or thornscrub, and rarely entering tropical deciduousfirr- naturalized in disturbedhabitats: essentially fiost fiee est. Southwestern Arizona sctuthto the Guaymas re- areas fronl near sea level to 1050+ m. A red-leaved gion and eastward to the Rfo de Bavispe region and cultivar, grown ofien as an ornamental, is sometimes the Ricl Yaqui drainage southeastof Hermosillo; near encounlered us tr wail'. sea level to 9-50m. Also Baja Califcrrniaand Baja Cal- Mpio. Cturyrrras:Bahfa San ('lrrkrs. roatlsitlc.!.tl.qt,r 81-.549.Mpio. ifirrnia Sur. The seeds, like those of Sebastianiupa- Mr)ctezurr)a:Rf0 Moctezurna,M()cterullit. llltitt )9(t. Mpio. L,tcho vctniano, are sometimes parasitized by a moth larva .joa:Par-cdoncito on Bahia'lirhari, ca. 2tl nri W ot Narojoa. Sunder.t and sold as Mexican jumping beans. 3966. Sebastiania bibcularis has previously been treated in Sa1;ium,but it lacks the fleshy seed testa characteristic SEBASTIANIA Spreng. of that genus. Following the circumscriptions of Sapium Trees rlr shrubs (in ours), rarely herbs; monoe- and Sebo.stittnia adopted by Webster (1991) and Mc- cious. Latex (at least in ours) milky. Pubescence Vaugh (199-5,pp.204-205), this speciesis best accom- mostly unbranchedor absent. Leaves usually alter- modated within Seba.stirmia,where it is also placed by nate, serrate(in ours) to rarely entire, penniveined. Kruijt (1996, p. 83). Specimenspreviously ref'erredto as Inflorescencesbisexual, terminal (rarely axillary), v'ar amplum appear to diff'er solely by the possession of spicate bracteatethyrses; I flowers solitary or rarely slightly broader leaves, and we believe that it is best sub- in few-flowered groups at the lower nodes of the merged within the circumscription of a monotypic species. thyrse; d flowers clustered in the upper nodes of the thyrse; bracts biglandular at the base. Staminate Mpio. Gen. Plutarco E,lfasCallcs: 35 rlr W of Sonoyta on MEX 2, Webster l97Ot). Mpio. Granados or flowers with a 3-lobed calyx; petals 0; stamens 2 or Bacade

Rancho La Lechugullla, 127O-1700 m, Guizar N. Leaves alternate, opposite or verticillate, usually ser- 2347 (holotype MEXU, not seen). rate, penniveined; stipules glanduliform. Inflores- cences mostly bisexual, terminal, spicate, bracteate Hierba de la flecha. Large shrub to small tree; re- thyrses; bracts biglandular at the base; I flowers at the productive in December, March, July to September, so lower few nodes of the thyrse, I per bract; d flowers far as known. Tiopical deciduous forest in southeastern at the upper nodes of the thyrse, l-several per bract. Sonora, 225-600 m. Also nearby southwestern Chi- Staminate flowers with a 2-lobed calyx; petals 0; sta- huahua to northern Nayarit. mens 2 (3). the filaments connate at the base. Pistillate The Sonoran plants have been called Sapium ap- flowers usually with 3 distinct sepals;petals 0; ovary pendiculatun (Miill. Arg.) Pax & K. Hoffm., but ac- 2 or 3 locular, with I ovule per loculet styles 2 or 3, cording to McVaugh (1995, pp.2O7,2O8) this appears entire, united at the base. Fruit capsular, with a hard- to have been an enor. Sapium appendiculatum fnow ened, 3-horned gynobase persisting afier dehiscence. treated as Sebastiania appendiculata (Miill. Arg.) Seeds carunculate or ecarunculate. Kruijtl reportedly differs by lacking the large petiolar About 30 speciesmostly in tropical and arid regions glands that are present on our plants. crf the Americas, but several in the Old World; ca. 12 Mpio. Alarnos: roadsidc near Rancho La Junta. at the junctictnctf speciesin M6xico. Reference:Rogers 195l. Rio Gua.jariryand thc Rio Mayo,.Slerrllrann9-l l1l. rd to Las Chin- l. Leaves lincar, thc nrarginscntirc ()r minutely toothed at thc acirs I knr NE of'I:l T:ryntrco. 25 Aug 1993. Murtin <,tul .s.rt. apex S. lineuri/itliu l' [.cavcs ()vatc.thc rrrarginsstrongly spinosc-tStillingia gvntnogvna Pax & K. ico by Ses.sd& MoE:ino (holotype G, not seen, photo Hoffm., in Das PflanzenreichIV. 1.17.l [Heft 52]: Mus. neg. 34162]!). [Field 196. 1912.-TYPE: United States,Califbrnia, San Sebastiuniuytltneri Rosc, Cbntr. LLS. Natl. Herb. I: |12. llJ9l. Diegcrnear boundary monument, ltl75, Pulmer 449 TYPE,: M6xico, Sonora.lMpio. Alanrosl. Alrrrros. 2(r Mar 8 Apr (lectotypeGH!, chosenby Rogers 1951,p. 2481). 189O.I'uhncr 10-1.Al LJSthcrc arc tirur shcetsol'this collection. The one that is in thc typc collcction(#c)llO99l) and labclcdas Herbaceous perennial (although flowering in the the type (- lectotypc) is ir stcrile hranch. An is()lectotypc first season), sometimes woody at the base; reproduc- (#41593\\ possesscsmaturc iiuit. tive nearly throughout the year. Widespread in the So- Sclut.rlittnitt ntnirt:ii Maury. l-a Naturalcza 2: t.105 ).106( ;107). noran desertscrub of northwestern Sonora eastward to Iu94. TYPE: Mdxico. Sonorit. lMpio. AIanxrsl. Alarrxrs. the collcctor and tlatc not given (probably at P. not scen). the vicinity of Quitovac and southward along the coast to the vicinity of Puerto Libertad; commonly on sandy jumping Brincador, bean. Large shrub to slender scrils,near sea level to 225 m. Also southeasternCal- tree l0 12 m tall. Flowering March, and June to Au- ifbrnia, Baja Califbrnia, Baja California Sur, western gust; fruiting mostly at the beginning of the summer Arizona, and southern Nevada. rainy seasonin July. Tropical deciduousforest in east- central and southeasternSonora:275-975 m. To Jal- Mpio. San Luis R. C.: Sierra del Rosario. in snrall wash, /.i,1.qar isco and Veracruz, and in Baja California Sur. The 2(i69,\.Mpio. Gcn. Plutarco Elfas Callcs: 3O mi SW of Sonoyta on seeds are ofien parasitized by moth larvae and sold as rtl to Pucrlo Pciasco. Sltreve7591. Mpio. Pitiquito: LU km NNE of' Punta Cirio. Sierra Bacha. 7.2 knr bv air SB of Pucrto l-ibcrtad. Van Mexican jumping beans. Devender 9I 2-5. Both Wiggins (1964,p. 807) and Standley(1923,p. 648) list Sebastiania pringlei S. Watson as a synonym SrrllrNcr,q sprNLrLosATorr. in Emory, Not. Milit. Re- of S. pavoniana. Howeveq according to Grady Webster conn. l5l. 1848.-TYPE: United States,California, (pers. comm., 1993), S. pringlei is a separatespecies but does not occur in Sonora. desert west of the Colorado [River], 28 Nov 1846, Emory .s.n.(holotype NY!). Mpio. Mazatiin: Sierra de Mazatain, Gentn 16591. Mpio. Onavas: 'l 6.3 by rd W of Tepoca, ca. 2 km SW of MEX 16, 28'27'36.,1"N, Supiurn annuum Torr., Botany of the Boundary, lin Ernory, Rep. 109"19't l"W, Wilson 91-1. Mpio. Alamos: Sierra de Alamos, Gen- U.S. Mex. Bound.2, pt. ll: 201. 1858. Stillingictannua (Tctrr.) tn 1870a: Rio Guajardy between Todos Santos and Los Aguaros, Miill. Arg. in DC., Prodr. l5(2): I160. 1866.A nomen superfluum 27'38'N, 108'57.5'W Felger 91-55. listing the earlier Sti//lngiu spinulosa in synonymy.

Spring/early summer annual, sometimes quite ro- STILLINGIA Garden ex L. bust. Sonoran desertscrub; 125-150 m. Northwestern Trees, shrubs, herbaceous perennials, or rarely an- Sonora in the open sandy desert west of the Pinacate nuals; monoecious. Latex milky. Pubescence absent. volcanic complex. Also extreme southwestern Arizo- VOLUME 16.NUMBER I Euphorbiaceae of Sonora 65 na, southeasternCalifornia, and northeastern Baia Cal- to triangulaq smaller than but similar in shape ifornia. to the lower leaves: terminal d flowers usually with3stamens ..7.sp. Mpio. San Luis R. C.: 30 mi E of San Luis on MEX 2, Felser 57641 5' Leaves at the branch ends linear and propor- l0 mi N of El Golfo. sandy plain, Felger 75-7-l'. sand plain 7 mi tionally narrower than the lower leaves:termi- NE of Sierra del Rosario. Felper 20-157. u o"*:^ mo:tlvw:th 1 t ":1 :'i-:i: r ,u^,,,,o TRAGIA L. TnRclR JoNESIIRadcl.-Sm. & R. Govaerts. Kew. Bull. Shrubs, herbs, or vines (ours are perennial herbs or 52: 48O. 1997. Based on Tragia scandens M. E. vines); monoecious. Latex absent.Pubescence of un- Jones,Contr. W. Bot. l8: 49. 1933; not Tragia scan- branched,often urticating hairs. Leaves alternate,sim- dens L., 1754.-TYPE: M6xico, Sonora, [Mpio. ple (or rarely, as in Z. laciniato. palmatisect),sharply Guaymasl, Guaymas, 2'7 Jan 1927, Jones 23300 serrate to dentate (in ours), palmiveined. Inflores- (lectotype POM[#1 625521!, here designated). cencesmostly bisexual. axillary or terminal, racemose Vigorously twining perennial herb, the with a few proximal ? flowers and f'ew to numerous Quemador. inflorescencerachis characteristicallypossessing tack- d flowers. Staminate flowers on articulated pedicels; shaped, stipitate glands (rarely nearly glandless,e.g., sepals3 6; petals 0g stamensusually 3 (rarely 2 6 or Wiggin.s5972): reproductive at various seasons.Often more). the filaments fiee or united at the base.Pistillate in shaded habitats in Sonoran desertscruband thorn- flowers on articulated pedicels; sepals 3 6; petals 0; scrub. fiom the vicinity of Altar and coastalSonora to ovary usually 3-klcular. with I ovule per locule; styles the southwestportion of the state, sea level to 425 m. 3, entire, united at the base.Fruits capsular.Seeds eca- Also Baja runculate. Califirrnia Sur, and to southern M6xico. These Sonoran plants have been treated as Tragia Mostly tropical and subtropical regions in both umblyodontu (Miill. Arg.) Pax & K. Hoffm. (e.9., hemispheresbut best representedin the New World Wheeler 19.15.p. 109; Wiggins 1955, pp. 346 347: and Africa; 150 specieswith ca.20 in M6xico and five Wiggins 1964, p. 798) but represent a speciesquite in Sonora. The Sonoran representativesare erect t() ditferent fiom L amblyodonta. Tragia jone.sii is sim- ascending,trailing, or twining perennialherbs that fie- ilar to Tragitt sp., fiom which it differs by its longer, quently possessurticating hairs. The specieshere treat- more slender pedicels, stipitate glands on the inflores- ed are variable and ofien difficult to distinguish fiom cences, and smaller seeds.Rarely, exceptions can be one another(especially in a dichotomouskey). Their found that blur the distinctions between them. distinctions are fufiher obscured by the presence of intermediates.Thus, our treatment clf this taxonomi- Isla Tiburtin: SW part ol central valley, ca. l3 nri S o1'Tccomatc, cally difficult group should be consideredpreliminary. vicinity of 2tl'-57'N. 112"27'W.Itelgt,r 17.1.)O.Mpio. C)quitoa:6 nri Ref-erences:Miller and Webster 1967; Urtecho 1996. E crt Altar. Hacicncla()quitoa (Cutting's Ranch). Wi.qgin.s-5922 (tJS). Mpio. Huatabanrpo:l.-5 km NW of Clrrrahuiroaon rd to Las Bocas. (at L Lcaves lcast thc upper oncs) conrporrnd.1 partcd St<'iturtttrtrt9-l -169.Mpio. Guaynrns:Playa la Manga. Bahia Algo- .....7'. lrciniuttt doncs, 29 Dcc 1982 Van l)tyt'ndcr t,t ul. .s.tt.Caiirin del NacaDulc. l' Lcavcs sinrple.not dividcd. h tlu(r 65-550. 2. Inlkrrcsccncc rachis usually with tack shaped glanclular hairs: petlicelol thc ? flower relativcly long and slcnclcr, thr- persistentbasc -1.-5nrnr or longer: scctls 1.0 nrnt rtr Tnncrn r-ACrrNrArA(Ton ) Mtill. Arg., Linnaea 34: 182. lcss in diamctcr. Plant vinc-likeand twining: dcscrtscruh 1865. Tragia urticifolia Michx. var.? lociniataTort., 'l anclthornscrub nrostly in cotstal Sonora . .jrnt.sii Botany of the Boundary, [in Emory, Rep. U.S. Mex. 2' Inflore'scencerachis lacking tack shaped glandular hairs Bound. 2, pt. ll: 200. 1858. TYPE: [presumably (somctlmes granular-glandularor rarely with stalked. present-day Arizona, Santa Cruz Countyl, on the glandular hairs in 7-rugitt sp.): pedicel ol' tlre ? flowcr relatively st()ut.thc pcrsistentbase mostly lcss than .1.0 Sonoita fRiverl, l5 Sep 1851, Wright 1795 (lecto- mm (rarcly to 5.5 rnm in 7'ntgitt sp.): seeds2.2 ntm or type NY!, designatedby Miller and Webster 1967, more in dianteter.Plants twining, decumbent,ascending p.294). ()r crcct: habitut and range vurious. 3. Plants vinelike and vigorously twining. . . 7-.sp. Erect to decumbent or somewhat trailing perennial 3' Plants erect to decumbent, if twining then only very herb, unique among the Sonoran Euphorbiaceae in weakly so at the ends of the branches. possessing evidently compound, palmatisect, three- 4. Young ? flowers with little-exserted styles, these parted leaf blades; May-October. Northeastern and shofter than the sepalsl stigmatic surface lacerate- papillose T. nepetifolitt var. disset'ta east-central Sonora in oak woodland, pine-oak wood- ,1' Young ? flowers mostly with well-exserted styles, land, and pine forest; 1350-2050 m. Also Chihuahua these often equaling or longer than the sepals; stig- and southeastern Arizona. matic surfaces nearly smooth to irregularly rough- ened. Mpio. Y6cora: upper Barranca E1 Salto, at the edge of Mesa El 5. Leaves towards the ends of the branches ovate Campafrero,28'21'36"N. 109'01',+4'W Felger 94-187; along Ar- 66 Steinmann and Felger ALISO royo El Kipor, just E of El Kipor on trail to Tiena Panda (Las late, and the terminal staminate flowers often possess Taunas),28'2,1'N, 108'33'35"W Van Deyender 95-965. Mpio. Can- 5 or 6 stamens. Also, the upper leaves are character- anea: Siena dc los Ajos, Las Cabafras.Cafl6n de Evans,3l'00'N, (the ll0'00"30"W Felger 92-805. Mpio. San Felipe de Jesfs: norlhern istically narrow bases are essentially as wide as Sierra Aconchi. Caj6n lnllerno, 7 mi by rd. W of San Filipe, the middle) and very sharply and finely toothed. 29'50'N. I 10"21'W ReichenbaclrcrI I 15. Mpio. Fronteras: 5 mi S of Esqueda on rd to Rio de la Tierra, Wiggins l176lt (SD). TnRcrn NEeETTFoLIA Cav. var. [as ct] DTssECTA Mi,ill. Arg. in DC., Prodr. l5(2): 933. 1866.-TYPE: M6x- ico flocation and collector not stated, but possibly Ttacte sp. made by Sessd & Moginol (holotype G-BOIS, not seen.photo DAVI). Rama quemttdora, ortija. Perennial herb, trailing to twining, and sometimes severely stinging; mostly De- Ortiguilla. Ascending to trailing perennial herb with cember to March. Sonoran desertscrub, thornscrub, slender stems; reproductive in responseto spring and tropical deciduous forest and the lower edge of oak summer-fall rains. Sonoran desertscrub,grassland, oak woodland; 7-5-1300 m. Ranging from Isla Tibur6n to woodland, and pine-()ak woodland in the eastern pafi southern Sonora. Also adjacent Chihuahua and south of the state; ca. 500 1680 m. According to Urtecho at least as far as Oaxaca. Roberto Urtecho (1996) has (1996, p. 164), the Sonoran plants belong to var. di.s- proposed naming these plants T. macvaugftil, but this ^recld, which differs from the other three recognized is still unpublished. varieties of T. nepetifttlia by its deeply toothed leaves There are two distinct morphological fbrms of this and red staminate flowers. Variety dis.sectctis known speciesin Sonora. Most collections are twining. vine- from southeastern Arizona, Sonora. Chihuahua tct Za- like perennial herbs, but occasionally lclw, ascending catecasand San Luis Potosf. to decumbent plants are enc()untered.These latter col- Wiggins & Rollins 69 trom 7 miles south of Santa lections also diffbr fiom the more robust, twining Ana generally resemblesthis speciesin habit, but the plants in being covered with long, stiff. spreadinghairs stigmatic surfaces are smooth, and the inflorescence reaching more than 2 mm in length. The two ibrms rachis is unusually glandular. The disposition of this are superlicially quite different, but we interpret the collection remains unceftain,and it possibly represents variation as environmentally induced. The trailing, a hybrid between T. nepetilolia and some other spe- densely armed plants are mostly from disturbed areas, cies. maybe Trtt.qiu.jont'.tii. and their habit and pubescenceappear to be the result Mpio. Y6cora: arroyo 3 :1 krrr NNW ol El Kipor (Qufpor). Vrrrr of growing in an open and "adverse" habitat. Besides I)ct't'tutt,r951 lO. Mpio. Alalnos: Sicrra Sagrrariho.ca..1 krn b1-r-d the growth form and pubescence, there appears to be W of Las Chinacasalong rd t() Taylnuco, Stcittrttttrtrt9-i -i(/.5.Mpio. no differences of taxonomic merit between the fbrms. Cucurpe: t3.7 nri ENE, ol ('ucurpc, akrng rd to Aguil Fria, 3 Oct but common-garden experiments are gain 19'79.Von I)cyettdcr & l?xtlin,s.ri.Mpio. Arivcchi: 2.2 tni by rd u desired to o1' Arivcchi, 2tt"55'N, 109'20"W I;elgtr 91-3(t5. Mpio. lnruris: further insights into the cause of this variation. We along MEX 2. 28 kni hy rd NE of the junction with MEX 15. ca. have also seen Sinaloan specimensof the low, densely 3(f53'N. If 0".10'30"W.Steitttnttnn 91.J. armed form. Steinmann 93-280 from the Sierra Saguaribo is TnecrR RAMosATcrrr., Ann. Lyc. N.Y. 2: 245. 1827.- noteworthy in possessing exceptionally large leaves TYPE: United States,Sources of the Canadian [Riv- and conspicuously papillate stigmatic surf'acesthat re- er, evidently in SE Coloradol, Long's Expedition, semble those of T. nepet{blia. The stigmatic surfaces summer 182O,James.s.n. (holotype NY!). of Tragict sp. are otherwise smooth to undulate. The significance of these differences is not yet For synonymy see Millcr and Wcbstcr 1967. pp. 23 1 233. apparent, but the plant may represent a hybrid with Z. nepeti- Ascending to decumbent perennial herb, rarely folia, which was fbund nearby. twining at the branch tips; time of reproduction inad- equately known for Sonora, elsewhere mostly April to Densely armed, ascendingto decumbentspecimens. Mpio. Alarnos: October. Dry grasslands in northeastern Sonora where El Paso,just above Rio Cuchujaqui, 26'40'3-5"N.108'49'30"W, Vcn it is known from a single collection at 1300 m. Wide- Det,ender 95-100: Sierra dc Alanos. Ro.se, Stundlet', & Rus.sell t2879 (US\. spread across the Great Plains to California and north- ern Mdxico. Twining specimens. Isla Tibur6n: waterhole at SE base of Sierra This species is very similar in appearanceto T. ne- Kunkaak, Felger 9290. Mpio. Alamos: Arroyo Gochico, I I km by petfolia, with which it is frequently confused. Both air E of San Bernardo, 27'23'.15"N, 108"43'30"W Steinmann 603. Mpio. Navojoa: Arroyo Masiaca, ca. 0.5 km N of Teachive de Ma- are trailing perennial herbs. However, in T. ramosa the siaca, 26"47'15"N, 109"13'5O"W, Van Devender 93-961. Mpio. styles of the young ovaries are relatively long and Moctezuma: between Huiisabas and Moctezuma, 29"50'N, slender, the stigmatic surfaces are not strongly papil- 109"30'W -/o,r'al155J (ASU). VOLUME 16.NUMBER I Euphorbiaceae of Sonora

DOUBTFUL AND EXCLUDED TAXA Euphorbia chamaesula Boiss. var. subdentata (Engelm.) Norton, Annual Rep. Mo. Bot. Gard. 11: Acalypha langiana Miill. Arg. 131. 1900; separateissued 1899. Euphorbia McVaugh (1995, p. 177) lists Sonora in the distri- esuliformis S. Schauer var. subdentata Engelm. in bution of this species.We have not seen any specimens Torr., Botany of the Boundary, [in Emory, Rep. U.S. of this taxon from Sonora. but it conceivable could be Mex. Bound.2, pt. ll: 192. 1858.-TYPE: San represented in the flora. Acaly"pha langiana is very Francisco Springs, Mar 1852, Parry s.n. (holotype similar to A. subviscida, but among other differences MO[#r4e164]t). the pistillate spikes are only axillary. Although the protologue gave the location as So- Acalypha obscura Miill. Arg. nora, White (1948, p. 232) statesthar this location is probably Ojo de San Francisco, in northwesternChi- Wiggins (1964,p. 793) implies that this speciesoc- huahua. Howeveq according to maps in vol. l2 of the curs in Sonora. However, he is almost surely referring United States War Department's reports of the Pacilic to Acal,vphaphleoitles, of which A. obscurct is possibly Railroad survey, there is also a San Francisco Springs a synonym. A photo of the type (Field Mus. neg.7127) at roughly 35"15'N, lll"40'W in present-dayCoco- shows a plant very similar to A. phleoides. nino County, Arizona. Although the type and the only other collecti

Reported for Sonora by Wiggins (1964, p. 810), but Euphorbia esuliformis S. Schauer this refers to D. populifolia. Boissier (1862, p. la7) cites a collection from So- Ditaxis tinctora (Millsp.) Pax & K. Hoffm. nora by Smith. He did not see this record but reported it on the basis of communication with Engelmann.Ap- Gentry's reference (1942, p. 165) is to this species parently he is referringto Euphorbia chamaesula. This based on a misidentified collection of Ditaxis Ruate- conclusion is based on the fact that Boissier also cites malensis. under E. esuliformis, again based on communication with Engelmann, Wright 1820 (the type collection of Euphorbia bartolomaei Greene E. chamaesala). Also, a Smith collection of E. cha- Listed by Oudejans (1990, p. 70) as occurring in maesula from Sonora at MO (apparently the one to Sonora. It is known to us only from the Baja California which Boissier refers) was originally labeled as E. esu- Peninsula and unlikely to be present in Sonora. lformis. Steinmann and Felger ALISO

Euphorbia esuliformis S. Schauer var. subdentata Euphorbia parryi Engelm. Engelm. Reported from the Rio de Bavispe region by White See Euphorbia chamaesula var. subdentata above. (1948), but the specimen cited is E. florida. Also re- ported for the state by Oudejans (1990, p. 306), but Euphorbia fendleri Torr. & A. Gray we have no evidence that it is present. Hemsely (1882-1886, p. 93) cites a Thurber speci- Euphorbia serpyllfolia men (K, not seen) from Sonora. We have not seen Pers. var. hirtula (Engelm.) L. C. Wheeler Sonoran collections of this species,and Thurber's col- lection was probably made before the Gadsden Pur- Acccrrding to Wheeler (1941, p. 235), there is an chase and from present-day Arizclna, where this spe- Edward Palmer collection of this variety reportedly cies is common. fiom Sonora, but the locality infbrmation is probably incorrect. This taxon is otherwise known fiom Cali- Euphorbia glvptospermn Engelm. ftrrniaand Baja California. First reported fbr Sonora by Watson (1889, p. 74), but the plants that he ref'erred to are E. abrctm.siana. Euphorbia uniglanduktsa S. Watson Euphorbio glvpto.spennd was also listed fbr the state Gentry's reference (1942, p. 170) to this speciesis (1990, by Oudejans p. 176), but we have not seen any based on misidentified material of Euphorbia diosco- Sonoran specimens,and it is unlikely to be present. reoides ssp. uttenuota. Euphorbia bifurcata Engelm., of which E. uniglunduloso is a synonym, is widespread Euphorbio hirta procumbens (DC. L. var. N. E. Br. in M6xico, including Chihuahua,but it is nor known (: Euphorbio ophthalmlca Pers.) fiom Sonora. Reported fbr the Rio de Bavispe region by White (1948, p- 285), but the specimen cited (White 2679, H u ra pt tl.t'undru Baill. GH) is var. hirtu. Variety prctcumben.s is distinguished Pennington and Sarukdn (1968, p. 2-58) state that fiom the typical variety by its krw, decumbent habit; this speciesoccurs in southwesternSonctra. However, generally smaller leavest and inflorescencesthat are we have no evidencethat it is either native or naturally usually only terminal on the main stem axes.Although persisting. Known otherwise from central Sinaloa tcl some Sonoran collections superticially resemble var. Nicaragua,it is occasionallycultivated in southwestern procumben.s Steinmann614 (RSA)1, le.g., in our opin- Sonora, and a grove of these trees is repclrted to occur ion these are only stressedplants of var. hirta. ln fact, near Navojoa, perhapsderived from planted trees (Al- the concept of var. procumben,r may be nclthing more berto Bfrquez, pers. comm., 1993). than a phenotypical morph of var. hirta growing under unfavorable conditions such as water stressor grazing. Manihot caudato Greenm.

Euphorbia melanadenia Tclrr. var. subinappendiculata Gentry (1942, p. 167) reportsthis speciesfor Sonora Engelm. but does not cite a collection. The specimen that he lists for Chihuahua was annotated by Rogers and Ap- See Euphorbia cineroscens above. pan as Manihot davisiae (see nclte under this species). See also discussion tnder Manihot sp. Euphorbia mctculato L.

Cited fiom "Sonora, Alta, Coulter, 1449" (K) by Mttnihot chlorostictct Standl. & Goldman Hemsley (1882-1886,p.91), the specimenis E. t:ap- Reported fbr Sonora by Wiggins (1964, p. 806), but itellata. Although E. maculata has been a "weed" in these plants 'areM. davisiae. Tucson since at least 1917, and conceivably could be present in Sonora, it is here excluded for lack of a P h1,llanthus galeottianus Balll. specimen. The report of this species from the "vicinity of Euphorbia ocymoidea L. var. barnesii (Millsp.) Magdalena, Sonora" by Wiggins (.1964, p. 776) is McVaugh based on a misidentified specimen of P. polygonoides. The report of this variety for Sonora by Van De- Sapium appendiculatum (MUll. Arg.) Pax & K. vender et al. (1995, pp. 413-414) is based on typical Hoffm. Euphorbia ocymoidea. Variety barnesii, which we be- lieve is best treated as E. barnesli (Millsp.) Oudejans, Recorded for Sonora by Gentry (1942, p. 168), but does not occur in the state. this is apparently a misapplication of the name, and VOLUME 16. NUMBER I Euphorbiaceae of Sonora 69 these plants belong to Sebastiania cornuta (see note BnEcxoN. G. J. 1975. Cnidoscolus section Cal ,-pto.ro/en(Euphorbi- under this species). aceae) in Mexico and Central America. Unpublished Ph.D. dis- sertation. University of California, Davis. 463 p. BRowN, D. E. [ed.]. 1982. Biotic Communities of the American Tragia amblyodonta (MUll. Arg.) Pax & K. Hoffm. Southwest United States and Mexico. Desert PL 4:l-312. BLTRCH,D. 1966. The application of the Linnaean names of some Sonoran plants referred to this taxon (e.g., Wiggins New World species of Eaplrorbla subgenus Clutmaes,-ce.Rhodora 1964, p.798) representTragict jonesii, a speciesvery 68: 155-166. different from true T. amblyodonta. BLTRGER,W., aNo M. Hrr'-r. 1995. Euphorbiaceae.pp l-169. In W. Burger [ed.l. Flora Costaricensis # I l3 (Fieldiana. Bot. 36). Blrnetrez, A.. A. Manririez-Ynizen, aNo T ra g ia urt icfo lia Michx. R. S. FEr_cER.In Press. Biodiversity at the Southern Desert Edge in Sonora, Mexico. 1n Recorded by Wiggins (1980, p. 135), but this spe- R. Robichaux [ed.l, Ecology and conservation of thc Sonoran Desen llora: a tribute to the Desert Laboratory. University of Ar- cies occurs in easternUnited States.and we have seen izona Press.Tucson. no specimens from Sonora. We are uncertain to which nNo P S. M.qnrrN. 1992. From the high Sierra taxon Wiggins is referring. Madre to the coast:changes in vegctationalong highway 16, May coba Hermosillo. pp. 239 252. In K. E Clark. J. Roldan-Quintana and R. Schnrid feds.l.Northcrn Sierra Madrc OccidentalProvince . AC]KNOWI-EDC;MENTS M6xico. guidebook. El Paso Geological Society, El Paso. Rogers McVaugh and Grady L. Webster provided C'onnnt.t.,D. S.,,qNDM. C. JouNsron. 1970. Manual of thc Vascular Plantso1'Tcxas. Texas ResearchFoundation, Rcnner. l88l p. countless indispensable comments on many groups Ct

Godman and O. Salvin [eds.], Biologia Centrali-Americana. R. H. phorbia of the section Tithymalu.soccurring north of Mexico. R"p. Porter and Dulau & Co.. London. (Annual) Missouri Bot. Gard. 12: 85-1,{,{; plates I l--52. Hor-ucneN, P K., N. H. HolvcneN, eNo L. C. BrnNErr. 1990. Index OUDEJANS,R. C. H. M. 1990. World catalogue of species names Herbariorum, 8th ed. (Regnum Veg. 120). 693 p. published in the tribe Euphorbieae with their geographical disrri- Hur-r, M. J. 1979. A monograph of Eu1:thorbiusection Tithvnalop- bution. Oudejans (self published).Utrecht. .144p. .rl^s.Unpublished Ph.D. dissenation. University of Michigan, Ann Prx, F. ANDK. HoFFMANN.1912. Daleniltertia, in Das Pflanzenreich Arbor. 276 p. IV I'17. v [Heft -52]:268 21O. (Euphorbiaccae) 198,1.A review of Euphorbiu in Baja Cal- PErNrNctoN.T. D.. rNo J. SARUKHAN.1968. Arboles tropicales de ifornia. Ann. Missouri Bot. Gurd. Tl: lj2l-1O27. M6xico. Instituto Nacional dc InvcstigacionesForestales. M6xico (Ett INc;nlr,t, J. 1964. Argtthtunniu guatemalensi.\ and A. tincktriu D.8.113p. phorbiaceae). Brittonia 16 27 I 215. R.u)cLIFFESMtrH. A. 1973.Allonrorphic f'crnaleflowers in thc genus 191O.Ar,qvtlumniu. pp. 939 942. /n D. S. Correll and M. Acult'pfut (Er.rphorbiaceac).Kev Bull. 2ll: 51.5 529. C. Johnston.Manual of thc Vascular Plants of Tcxas. Texas Re- 1976. A new combinatitln in Acultplta (Euphorbiaccac). scarch Foundation,Renncr. ltl[3] p. Kev Bull.3l: 226. 198O.The gcncric liniits of Ar,qvthamnizr(Euphorbiaceae) l9ll7. Euphorbiaceae,pan I. pp. | -107./rr R. M. Polhill dcfined. (ientes Herh. ll:121 1f6. led.l, Flora of Tropical East Af'rica. A. A. Balken.ra,R()ttcrdanr. JoHNSTON.I. M. 1924. Expcdition of thc Calitbrnia Acadenry of RoAr-soN.E. H.. ANDK. W. At.l.ReD.1995. A working index of New Scienccsto the Ciulf of Califirrnia in l92l: thc botany (vascular Mexico vuscullr plant namcs. lst ed. New Mcxico Agricultural plants). Prrr'. Culif. Acud. Sci. scr. IV. l2: 9-51 l2lx. -7O2. Expcrimcnt Station RcscarchReport Las Cruccs. 19.10.New phancrogantsfionr Mcxico. lll. J. Arnold Arbor. Rcrc;uns.D. J. 195l. A rcr,isionot Stillingiu in thc Ncw World. Ann. 2l:253 265. 'l'eras Mi.r.xturi Bor. Gord. -ltl: 207 l5c). JottNsroN, M. Cl. 1959. Thc' spccics of (irrtar (lruphorhi- ,rxn (Euphor, aceae). .loarhlV. Nuturuli.st -l: 175 20.1. S. Ci. App,rN. 1973. Munilutt, Manihotoidcs 197.5.Studics of Il'tcEuphttrbra spccicsof thc Chihuahuan biaceac). l"l. Ncotrutp. Morut.q. 13:. | 2-72. Desert region and adj:rccnt areas. ltrrrl,q/rlid5: 120 l-1-1. Rzeoowsrt. J. l97lt. Vegetacitindc Mdxico. Etlitorial Lirrrusa.\Icir .132 198O. Ilcrnurdiu nnrici.loIiu vlt'. irtttutttila.i (Euphorbi- ico. D. Il p. luccac),ncw varicty tiorrr thc Chihuahuan Dcscrt rcgion. /'/nlo- and Ci. Clrldcrtintlc Rzctlouski. 19t37.Nota sobrc I'-u1tlutr, Itt.qiu46:2lJl 2U2. ltia .stttnniae(Euphorbiaccac). (illl. .!rr'. Mtr. 32. 75 71. Ksanxsy. T. H.. rNo R. H. Pr-.ler.r-s.l9(rO. Arizona Fkrra.2nd cdi Scnc;nt.r.t.C. J. P lgUl. Oil plantsin lithiopia.tlrcir laxononty ancl tion with suppler)lentby J. T. Howcll and Ir. Mc('lintock. LIni, agricultural significancc.Agricultural rcscarchrcport 92 l. Centre vcrsity of California Prcss.Berkclcv. l0tt5 p. lbr Agricultural Publishing ancl L)ocunrcntati()n.Wa!eningen. Kpurrr, R. Cl. 1996.A tlxonorrricnrono-9raph ot SultiuntJucq..,4n Ncthcrlands. ()rnoslocltts(Baill.) Hurus., I)LtvigneuudiaJ. Lcionarduncl Sr'h,r- Ssnr.vg. tr 195l. Ve-getatronof the Sonoran l)eserl. Cornrgie lnst. o(t'()l()r1Hcrchst. (Errphorbiaceaetribc Hippontil:ncrcl. Ilibli()th. Wu.slt.Pultl. -59l. /r F. Shreve and I. L. Wiggins. Vcgetationand Btt. 146: I lO9. Flora of thc Sonoran Dcscrt, vol. l. Wasliington,D.C. 192 p. Lavant'x. J. B. A. Il M. lTttlJ.l:uphorbcs. pp. -1ll .1.11).1lr lincy- SraNot-gr'.P C. 1923. E,uphorhiaceae,pp. -595-653. In Trccs ancl clop6die M6thodiquc Botaniquc Vol. f. Chez Panckouck. Paris. Shrubsof Mcxico. Contr. U.S. Nurl.Harb.23 I l1)1 . 771 p. ANr)J. A. Sluysnvanr. 19,19.Euphorhiitccuc. pp. l5 170. Levrn. G. 199,1.Systcrnatics ol the Aculvltlut tulilrtntittt complex In Flora ()l Cuiltcmala, pztrt 6 (F it,ldiutut. IJttr. 21). (Iitrphorbiaccac). Mudnrltt 4l: )51 265. TIIF.T-r.trN(;.A. 1917. Iiuplutrbiu scct.;1rrl.ro7;/rr/lutrt, p1t. 1)) 1'/L).lrt MARIIN, B. D. f 995. ('nttrtt Monoecious morphs in culifontitLts P. Aschcrsonand P GracbncrIcds.]. Srn. Nlittclcur.I:1.. lol.7. ( liuplrorbiaceac). Mudnfto 42: 323 33 I . TLTRNA<;IT.W. V.. exn A. [-. HI\( Kr.r,r.l9-]E. Frcczing weather in MAR'r'iNItzGoHott.t.o. M. 1996. Contribucirin al conocinticnto dcl rclation to plant distrbulronin thc Sononrn l)cscrt. Erzrl.Mtnogr. g3nero Cruton (E,uphorbiaccac), cn eI cstado dc Cucrrcnr. Mixico. tl: 529'.550. (lontribucionesdcl Hcrbario tie la Facultatldc Ciencias. LJNAM. TLtt

'. ,.\ro \ S. AR\{tsRLrsrER.1991. A synopsis of the neotropical Kearney and R. H. Peebles, Arizona flora with supplement. Uni- specics of Dulccfutntpitt (Euphorbiaceae). Bor. J. Linn. Sot.. lO5 versity of Calilbrmia Press, Berkeley and Los Angeles. lO85 p. 137 177. I 98 l. Euphorbiaceae.pp. l\l-117 . /n L. Benson and R. A. AND B. D. Weesrsn. 1972. The morphology and relation- Darrow. Trees and shrubs of the southwestern deserts. 3rd ed. ships of Dalechontpitt st'anden.s(Euphorbiaceael. Amer. J. Bot. University of Arizona Press.Tucson. 416 p. 59: 573-586. Wsrre. S. S. 1948. The vegetation and flora of the region of the Rio WsnRI-En, L. C. 1935. Euphorbia cepitelldrd. its synonymy and de Bavispe in northeastern Sonora, Mexico. Llottlia ll 229 302. range. Ilull. Torr. Bot. Club 62: -537-538. WIc;t;tNs.l. L. l9-5-5.Notes on certain Euphorbiaceaein the Sonoran 1936. Revision of the Euphorhiu ytlt'utrpa group of the Deseft. Canlr. [)utlley Herb. 4: 3.13-353. 19621.Euphorbiaceae, pp. 773-838. southwesternUnited States and ad.jacentMexico: a preliminary In Flora of thc Sonoran Descn, pp. lU9 1740. /n E Shreve and I. L. Wiggins, Flora treatment. Rull. T0rr. Rot. Club 63: 397--116. '129 45O. and Vegetation ol'the Sonoran Desen, 2 vols. Stanford University 1939. A miscellany of Ncu, World Euphorbiaceae:-ll. Press.Stanfbrd. 17.10p. Crntr. Gruy Herb. 127: 18--78. l9tl0. Euphorbiaccac,pp. I l2- 135. In Flora ol'Baja Cali- 1911. I')uphorbirrsubgcnus (-luttnuc.stt.t'in Canad:r and the lbrnia. Stanfirrd Llniversity Press,Stanfbrd. 1025 p. United Statcscxclusirc ol'sorrthernlrlorida. Rlttnlrtra43:97 151, Wolr, S. J. 1988. Gcorgc Engclmann typc spccintensin thc Her- 168 205. 221 lli6: platcs 6-5-1.(r(rll. bariurn of the Missouri Botanical Carden. Ann. Missouri Bot. 19.15.Euphorbiaccac. p1.r. lO-5 l(D. ln C. Y. Monon. Mex- ()urd.75'. l6O8 1616. iczrnphancroglrrr: dcscribcclby M. E. Jones. C'onlr'.tl.S. Natl. Yr-rrraN. D.. L R. VAN DEVIINDBn.P Jr-.NxrNs.AND M. FrstJBEtN Htrb.29: lt7 ll6. f 995. The Rio Mayo: a history of studies.J. SouthW.37 294 1960. Iruphorbiaceac.pp. 50I 520t 1058 l0-59. ln T. H. 1.1s.