124 & S U C C U L E N T J O U R N A L (U.S.). V o l 58 CHISOSENSIS (Anthony) Comb. Nov. DAVID J. F E R G U S O N 6401 B Coors SW. Albuquerque, NM 87105

Opuntia chisosensis ( A n t h o n y ) Fergu- son, comb. nov. Opuntia lindheimeri var. chisosensis A n t h o n y , 1956. A m . M i d i . Nat., V o l . 55:1, 252 ( f i g . 26).

HOLOTYPE : A n t h o n y 223, A p r i l 8 & July 17, 1948, deposited at the U n i v . of M i c h i g a n , A n n A r b o r , M L

TYPE LOCALITY : Basin of Chisos M o u n - tains, Big Bend N a t i o n a l Park, Brew- ster Co., Texas.

This is an attractive species of Op- untia w h i c h has thus far been f o u n d i n the Chisos mountains in Brewster County, Texas and in the Sierra del Fig. 1. Opuntia chisosensis i n f r u i t i n Carmen i n northern Coahuila, Mexico. cultivation. August 1985. I t is characterized by an upright, bushy g r o w t h (to l m tall), and has mostly circular, bluish joints (about W i t h its contrasting bluish pads 15-20cm long). There are 1-5 spreading and yellow spines, this is the most to deflexed, b r i g h t yellow (rarely to s t r i k i n g Opuntia in its natural habitat. orange-red) spines (up to 6,5cm long) I t grows mostly above 1,650m (5,500ft) on the upper 2/3 or more of the pad. i n open woodland made up of mostly I n nature the spines t u r n black after j u n i p e r (Juniperus sp.), pinon (Pinus several years. The flowers are about cembroides Z u c c ) , oak (Quercus sp.) 6.5mm across and of an unusual, pale and Texas madrone (Arbutus texana yellowish-buff color. The f r u i t s are Buckl.). It is occasionally also f o u n d i n about 3-4cm long and obovate to more open grassland. Other prominent spherical w i t h few areoles. They ripen cactus and succulents associates are glaucous reddish purple and usually Cylindropuntia imbricata (Ha w o r t h ) have several t h i n , s t i f f , yellow spines K n u t h , Opuntia engelmannii Salm-Dyck near the top. The seeds are tan i n (sensu Engelm. and B r i t . & Rose, non color and average 4-5mm in diameter. Benson) , O. phaeacantha var. brunnea

I t is the author's opinion that Benson's interpretation of the name Opuntia engelmannii Salm-Dyck is i n error. I t seems u n l i k e l y that the type specimen is an Opuntia ficus-indica (Linnaeus) M i l l e r as Benson believes. The author prefers to f o l l o w B r i t t o n and Rose's interpretation. This subject w i l l be discussed i n more detail i n a future paper. I t is also the author's opinion that O. engelmannii is not a variety of O. phaeacantha as Benson believes (thus his combination: O. phaeacantha var. discata). I n many thousands of sympatric specimens of both species observed i n the f i e l d , the author has seen only four possible hybrids. CACTUS & S U C C U L E N T J O U R N A L (U.SX Vol 58 125

Engelm. (sensu Engelm., non engelmannii). Benson's theory is not Weniger) , Echinocereus coccineus supported by the populations f o u n d i n Engelm. var. gurneyi (Benson) , E. the f i e l d . Weniger's interpretation is russanthus Weniger, Escobaria varicolor somewhat unclear, but he appears to (Tiegel) H u n t , Mammillaria meiacantha have equated O. chisosensis w i t h both Engelm., Agave havardiana T r e l . and O. engelmannii var. cyclodes Engelm. & Nolina erumpens (Torr.) Wats. Bigelow and "O. engelmannii var. I n the past Opuntia chisosensis has cacanapa (Griffiths & Hare)" (nom. been quite misunderstood. When first nud.) w h i c h come f r o m eastern New described it was placed as a variety of Mexico and f r o m near Encinal and Opuntia lindheimeri Engelm. Benson Laredo, Texas, respectively. considered it as part of a h y b r i d Both O. engelmannii and O. lind- swarm between O. phaeacantha Engelm. heimeri are f a i r l y easily distinguished and "0. phaeacantha var. discata f r o m O. chisosensis. They are both (Griffiths) Benson & Walk." (=0. much larger i n stem (pads usually at

2 var. brunnea Engelm. was described f r o m E l Paso, Texas, and was clearly applied to the common southern variety of O. phaea- cantha w h i c h is f o u n d growing in mostly mountainous areas. Benson uses varieties major and phaeacantha somewhat at random for these (based on useless spine traits). Varieties major Engelm., phaeacantha (=var. nigricans Engelm.), as w e l l as var. camanchica (Engelm. & Big.) Benson should all be considered synonyms, and are all based on the common (somewhat less robust) northern variety of mountainous habitats. Weniger's interpretation of var. brunnea is somewhat unclear, but his photo is of O. macrocentra. The varieties and synonyms of O. phaeacantha w i l l also be the subject of a future paper.

Echinocereus coccineus var. gurneyi is a currently illegitimate combination w h i c h w i l l soon be properly published in a revision of the red-flowered Echinocereus of the U n i t e d States.

^ Weniger considered O. chisosensis to be the same as O. engelmannii var. cy- clodes. He seems to have also mixed the Chisos Mountains population of O. engelmannii var. engelmannii into this interpretation, but this is uncertain. The Chisos Mountains plants do have yellowish spines but have nothing to do w i t h var. cyclodes. The variety cyclodes grows only i n eastern New Mex- ico in the drainages of the upper Pecos and upper Canadian Rivers. I t is a weak variety characterized by large seeds (for the species), smaller than average f r u i t , less woody, thinner joints of a bluish color, and more slender (often fewer) yellow spines than i n the typical variety.

^ Weniger also apparently confused some chisosensis plants w i t h Griffith's O. cacanapa. This was described f r o m Encinal, Texas, and seems to be the same as Griffith's O. tricolor f r o m near Laredo, Texas. Weniger improp- erly placed O. cacanapa as a variety of O. engelmannii, leaving it as a nomen nudum. Benson placed O. tricolor as a variety of O. lindheimeri. Based on the author's experience, it w o u l d seem that neither name has any connection w i t h O. chisosensis, and that both are probably synonyms of O. lindheimeri. I t is u n l i k e l y that either name deserves f u l l varietal rank, but more study of these plants is needed. 126 CACTUS & S U C C U L E N T J O U R N A L (V.SX V o l 58 Plants have been f o u n d by the au- thor near Saltillo in southern Coahuila and northern Zacatecas, Mexico, w h i c h may represent a f o r m or variety of O. chisosensis. These occur i n similar habitats w i t h similar associated flora. They d i f f e r f r o m the Big Bend plants m a i n l y i n having slightly heavier, cream to white colored spines. They have the same g r o w t h f o r m and fruits, but the flowers have not yet been seen.

8U Fig. 2. O. chisosensis, a small plant g r o w i n g i n the Chisos Mts., March 1981. least 25cm long), flowers (usually at least 7cm i n diameter) and f r u i t (usually at least 4.5cm long, typically much larger). The seeds of both species are smaller, usually 3mm or less i n d i - ameter (occasionally to 4mm i n O. en- gelmannii var. cyclodes). The seedlings of both O. engelmannii and O. lind- heimeri have the spines m o d i f i e d into Fig. 3. O. chisosensis, Chapultepec, hairs w h i l e those of O. chisosensis do Coahuila, Mexico, August 1985. not. The true kinship of O. chisosensis w o u l d seem to lie closest to the species of the O. phaeacantha group. This group includes O. phaeacantha, O. spinosibacca A n t h o n y , O. azurea Rose, O. macrocentra Engelm. (=0. violacea Engelm.), O. aureispina (in press), and Opuntia sp. (l=horstii, a horticultural name of w h i c h the types were lost in World War II). These species all have the same basic vegetative and repro- ductive morphology as O. chisosensis (though they tend to have proportion- ately narrower f r u i t and i n O. au- reispina the f r u i t becomes dry). These species d i f f e r m a i n l y i n coloration, number and size of spines, and i n g r o w t h height (the later is usually Fig. 4. O. chisosensis i n flower i n c u l t i - more a f u n c t i o n of environment). vation, May 1985. CACTUS & S U C C U L E N T J O U R N A L (U.S.). Vol 58 127

ACKNOWLEDGEMENTS: B r i t t o n , N . L . & J.N.Rose, 1937. The Thanks are extended to Steven Cactaceae, Abbey Garden Press Brack o f Belen, New Mexico, who re- reprint. viewed this article. Photographs are by Engelmann, G., 1849. PL Fendl., Mem. the author. A m . Acad. 4. , 1850. PL L i n d . I I , Boston Journ. Nat. Hist. 6. , 1857 (preprint 1856). Proc. A m . Acad. 3. LITERATURE : , 1857. U.S. Senate Rept. A n t h o n y , M . , 1956. The Opuntiae of E x p l . & Surv. Rt. Pac. Ocean. Bot. the Big Bend Region of Texas, A m . 4. M i d i . Nat., 55:1, 225-256. , 1859. Emory Rept. U.S. & Benson, L . , 1982. The cacti of the Mex. Bound. Surv. 2. U n i t e d States and Canada, Stan- Weniger, D., 1970. Cacti of the South- f o r d U n i v . Press. west, U n i v . of Texas Press.

The F I F T H E A S T E R N C A C T U S A N D S U C C U L E N T CONFERENCE WHEN ? September 26th, 27th and 28th, 1986 W H E R E ? Ramada Hotel (Downtown), 111 Carlton St., Toronto, Canada WHO ? Steven Brack: "Mesembs in Habitat" "Conservation in Practice" M y r o n Kimnach: "Treasures of N a m i b i a and South A f r i c a " " L i t t l e K n o w n Succulents" Susan Lawrence: " A n O f f i c i a l V i e w p o i n t on Conservation" C. Wm. Nixon: "Sempervivums and Related Genera" John Pierce: "The Home Solar Greenhouse" John Pilbeam: "Mammillarias" "Gymnocalyciums"

ERRATA Several errors were introduced by the publisher in the paper, "Annual G r o w t h Bands in a Tropical Dry Forest Cactus, Lemaireocereus aragonii" by G. W. Otis and R. E. Buskirk in the January-February issue of the Journal ( V o l . 58:1, pp. 25-29. 1986). The publisher and editor accept responsibility for these omissions and ask that you correct your personal copies of that issue. The corrected text should read: Page 25, 3rd paragraph: "This species is endemic to the seasonally dry region of northwestern Costa Rica..." Page 28, table 1: Lemaireocereus aragonii should be L . eichlamii. The missing text reads: "Lemaireocereus aragonii = Marshallocereus aragonii, Costa Rica, Distinct, B r i t t o n and Rose, 1920: p. 92, Fig. 135; Backeberg, 1977: p. 301". Page 29, ACKNOWLEDGEMENTS : "Carlos Salas, manager of the refuge, Juan Rodriguez, w i l d l i f e biologist, and Roxana Diaz of Costa Rica Expeditions provided logistical support.