The JapaneseSocietyJapanese Society for Plant Systematics
ISSN 1346-7565 Acta Phytotax. Geobot. 61 (1): 49-54 (2010)
First Chromosome Countsfor Four Familiesof Malpighiales
KAZUO OGINUMAi AND HiRosHi ToBE2*
iDetpaf'tment of'Environmental Sciences, Iiaculty ofthtman L･lfe andEnvironmental Science, 2Deparment 1 The erdcr Malpighia]es, which cornprises 39-40 families of fiowering plants, are poorly understeod in terms of their morphological characters and the relationships ameng the families. Here, we present the first chremosome counts ofIrvingiaceae, Ixonanthaceae, Lacistemataceae, and Peraceac, based on Qne or two species each, using somatic cells from young Leaves. The chromesome numbers were 2n = 3e for Jrvingia maJcu?ana (lrvingiaceae), 2n == 28 for ixonanthes i(rosandra and l. reticutata CIxonanthaceaej, 2n = =:- 44 fot Lacis'tenza aggregatum (Lacistcmataceae), and 2n 36 for enaetocar:pus castanocaqJus (Pera- ceae), The Telationships ofindividual famiHesbased on chromosome numbers are discussed brlefiy, Keywords: chromesome numbcr, Irvingiaeeae, ixonanthaceae, Lacistemataceae, Ma]pighia]es, Peraceae The order Malpighiales comprises 39 to 40 Materials and Methods families (Stevens 2001 enwards, APGllt 2009, Haston et aL 2009), among which the phyloge- The species studied are listed in [lable l, along netic relationships remain unclear (Soltis et al. with collection data and chromosome numbers, 2007, Wurdack & Davis 2009). Morphological Somatic chromosomes were examified using and molecular analyses are needed to better un- young leaves collected from trees growing in the derstand the relationships of individual families. wild or in botanical gardens. The methods ofpre- In terms of chrQrnosome numbers, which often treatment, fixation, and staining for chromosome reflect the evolutionary relationships among fam- observations fbllowed Oginuma et al. (1992). At ilies (e,g., Oginuma & [Ibbe 2006: Laurales) or least three to five cells were examined tQ deter- within families (e.g., Oginuma & Tobe 1997: Rhi- mine the chromosome numbers. zophoraceae), the Malpighiales are poorly stud- The terminology of chromosome morphology ied. Of the 39 to 40 malpighialean families, the based on the centromere position fbllows Levan chromosome numbers of 12 remain unknown: et al. (1964). We examined all published data on Centroplacaceae, Ctenolophonaceae, Euphronia- the Malpighiales using Chromosome Numbers of ceae, Goupiaceae, Irvingiaceae, Ixonanthaceae, Flowering Plants by FedQrov (1974), and serial Lacistemataceae, Lophopyxidaceae, Malesherbi- publicat{ons titled Index to Plant Chromosome aceae, Medusagynaceae, Peraceae, and Quiina- Numbers (Ornduff 1967-1968, Moore 1973- ceae (Stevens 2001 onwards). Here, we report the 197Z Go]dblatt 1981-1988, Goldblatt & Johnson first chromosome counts of fbur families: Irvin- 1990-2003). Infbrmation on chromosome num- giaceae, Ixonanthaceae, Lacistemataceae, and bers of individual families in the fbllowing dis- Peraceae, eussion was obtained from those publications un- ]ess otherwise stated. NII-Electronic Library Service The JapaneseSocietyJapanese Society for PlantPlantSystematics Systematics 50 ActaPhytotax.Geebot. Vol, 61 T4BLE1.Taxaoflrvingiaceae,Jxenanthaeeae,LucistemataceaeandPeraceae(Malpighiales)studied,voucherintbrmationand chrDmosorm.c numbers Taxon Collection Chromosomenumber Irvingiaceae lrvingia matayana Oliv. SINGAPORE. Bukit Timah, Ciginuma &Lum s.n, in 2n-30 2008 (KYO). Ixonanthaceae ixonanthes icosandffa Jack SINGAPORE. Bukit Timah, 7bbe & al. 1277 (KYO). 2n =.' 282n=28 L reticulata Jack SINGAPORE. MacRitchie, 7bbe & aL 1279 (KYO). Lacistemataceae Lacistema aggregatum Rusby MEXICO, Cha:lul, Chiapas, Tbbe & Qginuma 349 2nt44 (KYO). Peraceae C?laetocarpuscastanoearpevs THAILAND, Khao Yhj Nationai Park, ( igtnumas,n. 2n=36 Thwaites in 2oos (Kyo) relationships among the families to which those Resultsand Discussion genera are assigned. It appears worthwhile to pay more attention to this possibility in future chro- frvingiaceae mosome studies. The lrvingiaceae comprise eight species in the three genera Desbordesia Pierre ex Tiegh., ixonanthaceae frvingia Hook,£ and Klainedoxa Pierre cx Engl,, The Ixonanthaceae comprise 35 species in the which are distributed from Africa to Southeast five genera Allanthospermum Forman, Clyrillop- Asia in the Old World tropics (Takhtajan 2009), sis Kuhlm., ixonanthes Jack, Ochthocosmus We studied1 mala.yana Oliv., one of fbur species Benth., and Plt];llocosmus Klotzsch, all ofwhich in its genus, which had 2n == 30, The chromo- have pantropicai distributions (Takhtajan 2009). somes at metaphase gradually varied in length We studied two species ofixonanthes: l. ieosan- firom about 0.7 to 1.4 ptm (Fig, 1A, B), 0fthe 30 dra Jack and L reticulata Jack, both ofwhich had chromosomes, most had a median or submedian 2n = 28, The chromosomes at metaphase gradu- centromerc, although the centromere position in a]]y varied in length fi"om about O,6 to 1,1 pam in L several small ch romosomes was unclear. icosandra (Fig, IC, D) and fi:om about 0.4 to O.8 The base number of frvingia is likely x == 15, ptm inL reticztlata (Fig. IE, F). Ofthe 28 chromo- Previous molecular analyses have suggested that somes, many had a centromere at a median or Irvingiaceae are related to Linaceae (Davis et aL submedian position, although the centromere po- 2005, Tokuoka & Tobe 2006, Soltis et at. 2007, sition in several chromosomes in both species ' Korotkova et al. 2009), and to Caryocaraceae, was uncertam. Erythroxy]aceae, and Rhizophoraceae (Soltis et The base number of L:onanthes is likely x =: aL 2007). While the base number reported here 14. The inter-family relationships Qf the Ixonan- for frvingia is substantially different from those thaceae are uncertai.n, but molecular analyses of Caryocaraceae (n = 23), and Erythroxylaceae have suggested a weak relationship with Ochna- (n = 12), and for Rhizophoraceae (x = 14 or 16), a ceae (Tokuoka & Tobe 2006). Ochnaceae, how- base number ofx =: 15 has been reported for a few ever, likely have a base number ofx = 10 (Oginu- = 14 israre species of Linum (Linaceae) and swcrodesmis ma unpublished). A base number of.x (Pandaceae). The base number (x ::= 15) common in other Malpighiales, but occurs jn some Rhi- to ltvingia, Linum and Mierodesmis may suggest zophoraceae (Oginuma & Tobe 1997). NII-Electronic Library Service The Japanese Society for PlantPlantSystematics Systematics Junc 2010 OaNuMA & ToBE-Chromosome Counts ofMalpighalcs 51 -wr t pt A ･s B ,x" g " g "g""･A tki , g$/k: ; tt " .p "C ee . .. ". C D z' ' "S n" :S. . , v./ wa･ee-ee$: tik. eeNe t//'/' '"'' {1" / E F 1. st .f "sc. R"$llts esk e;; s'.C k , e F[a. t. Sematic chremesornes at metaphase in Irvingiaceae and Ixonanthaceae. A,C, E: microgTaphs. B, D, F: drawiiigs ofmi- = cregraphs in A, C, and E, respectively. A, B: lrvingia malayana (2n = 30). C, D: Jxonanthes icosandra (2n 2g). E, F/ =: ixonanthes retieuiata (2n 28). Scale bar, 2 um. NII-Electronic LibraryMbrary Service The JapaneseSocietyJapanese Society for Plant Systematics 52 Acta Phytotax. Gcobot. Vol, 61 Lacistemataceae and that the Peraceae are sister to the clade of The Lacistemataceae comprise 14 species in Rafflesiaceae and Euphorbiaceae s.stn (Wurdack two genera, Lacistema Sw, and Lozania Mutjs, & Davis 2009). Anatomically, the Peraceae are which are distributed firom central to southern clearly distinguished from Euphorbiaceae s.stn South America (Takhtajan 2009). Lacistema ag- (palisadal exotegmeni in having a tracheoidal ex- gregatum Rusby, which was studied here fbr the otegmen (Tbkuoka & [[bbe 2006). Given that == first time, had 2n 44. The chromosomes at Chaetocarpus has a base number ofx = 18 (9), the = metaphase graduatly varied from about O.9 to 2,3 Raffiesiaceae have x 11 or 12, and Euphorbia- pm (Fig. 2A, B) in length. Ofthe 44 chromo- ceae s.snt have diverse chromosome numbers somes, most had a median or submedian centro- such as n= 8, 9, 10, 11, 12, 13, the chromosome mere, although the centromere position in several number of Chaetocarpus is untikely to represent small chromosomes was uncertain. relationships with other families. To evaluate the The base number ofLacistema is likely x :=T 22 evolutionary implications of these chromosome (or 11), Thc Lacistemataceae are a sister group of numbers, more in±brmation on the chromosomes Salicaceae (Davis et al. 2005, Tokuoka & [[bbe of other genera and species ofPeraceae is needed 2006, So!tis et aL 2007, Wurdack & Davis 2009). in addition to an analysis ofthe phylogenetic rela- The occurrence ofx = 11 appears to be rare in tionships within the family. other Malpighiales, but has been reported for some Salicaceae (e,g,, Flacourtia, Hbmalium, References and Oncoba) and some Euphorbiaceae s,str. (e,g,, Aleurites, CopeTonia, Chrozophora,Ditta, .latro- APGM (The Angiosperm Phyiogcny Group). 2009. An pha, ildltcaranga, iUinllotus, and Suregadti). The update ef the Angiosperm Phylogeny Group classifi- = cation the base number ofx 11 may indicate affinities be- for orders and families offlowering plants: APGIil. Bot. J. Linn. Soc. 161: 10S-121. tween Lacistemataceae and Salicaceae, although Davis, C. C., C. O. Webb, K. J. Wurdaek, C. A. Jaramillo it occurs as a homoplasy in the Eupherbiaceae & M. J. Donoghuc. 2005. ExpTosive radiation ofMal- s.stn as well. This has to be confirmed with yet pighiales supports a mid-Cretaceous origin of mod- chromosome data from a basal-divergent clade in ern tropical rain forests. Amer. Naturalist 165: E36- the family phylogeny. E65. Fedorov, A. A. 1974. Ch ro tnosome Numbers ofFlowering Plants. Otto Koeltz, Koenigstein, Germany, Peraceae Goldblatt, P, 1981-1988, Index to Piant Chromesome The Peraceae comprise 135 spec{es in the five Numbers. Volumes fbr 1975-1978, 1979-!98], 1982- genera Chaetocampus Thwaites, Clutia L., Pera 1983, and 1984-･1985 published in l981, 1984, 1985. Mutis, Pogonophora Miers ex Benth., and 7]'igo- and 1988, respectively. Monogr, Syst. Bot. Missouri Bot. Gard,5: 1-553, 8: 1-427, 13: 1-224, 23: 1-264. nopleura Hook.t, which have pantropical distri- Geldblatt, P. & D. E. Johnson, 1990-2003. Index to Plant butions 2001 onwards), Chaetocarptts (Stevens Chromosorne Numberg, Voiurnes for l986-1987, castanocarpus which was studied Thwaites, here 1988-1989, 1990-199!, 1992-1993, 1994-1996, and =' for the first time, had 2n 36. Chromosomes at 1998-2000 published in 1990, 1991, 1994, 1996, 1998, and 2003, respectively. Monegr, Syst. Bot. Mis- metaphase gradually yaried from about O,5 to 1,1 souri Bot. Gard. 30: 1-243, 40: 1-238, 51: 1-267. 58: "rn (Fig. 2C, D), Of the 36 chromosomes, most 1-276, 69: 1-208, 94: 1-297. had a centromere at a median although position, Haston, E., J. E. Riehardson, P. PL Stcvens, M. W. Chase their in several small chromosomes positions &D. J, Harris, 2009. The linear angiospcrmphylog- were uncertaln, eny group (LAPG) III: a linear sequence ofthe fami- lies in APG III. Bet. J. Linn. Soc. 161: I28-131. The genera ofthe Peraceae are usually placed Korotkeva, N., J. V. Schneider, D. Quandt, A. Worberg, in the Euphorbiaceae s,lat, (e.g., Radcliffe-Smith G. Zizka & T. Borsch , 2009, Phylogeny ofthe eudicot 2001), Howevcr, recent molecular analyses haye order Malpighiales: analysis of a recaLcitrant clade revealed that Rafflesiaceae are sister to Euphor- with sequences ofthepetD group li intron. Pl. Syst, biaceae s.stn, excluding the genera of Peraceae, Evol. 282: 201-228. NII-Electronic Library Service The Japanese SocietySoolety for Plant SystematicsSystematlos − June 2010 OGINuMA ＆ ToBE Chromosome Counts of Malpighales A B 礁 軌 轟 騨 も 譲 罅 氏 磊 ．「 ．、 〆 4 、 麟 懸 臨 1 ＝ ・ 膨 衡 “ 蟹 、 ” 譜 薪 f 鱒 瀞 D 靉 8 ・ らゐ − ω 陀 1幽 な 籬． も ゜望 Q コ ら 瀞 答 ・ ゆ 轟 FIG．2． Somatic cbromosomcs at mctaphusc in Lacistemataceae and Peraceae． A ， C ： micrographs ． B ， D ： drawings of mi じ ro − ＝ ＝ graphs in A and C， respcctively ． A ， B ： L α cistema α ggregatum （2n 44）． C， D ： Chaetocarpus castan θ carpus （2n 36）． ScaLe bar 2 m ， μ ． 一 NII-ElectronicN 工 工 Eleotronlo LibraryLlbrary Service TheTheJapaneseSociety Japanese Society for Plant Systematics 54 ActaPhytotax.Gcobot. Vol. 61 Levan, A., K, Fredga & A. A. San dberg. 1964, Nomencla- reau for Plant Taxonomy and Nomenclature, Utrecht, ture for centromeric position of chromosomes. Here- TheNetherlands. ditas 52: 201-220. Radcliffe-Smith, A, 2001, Genera Euphorbiacearum. Moore, R. J. 1973-l977. Index to Plant Chromosome Royal Botanic Gardens, Kew. Numbers. Volumes for 1967-1971 and 1972 pub- Soltis, D. E., M, A, Gitzendanner & P. S. Soltis. 2007. A lished in 1973 and 1974, respectively. Oosthoek's Uit- 567-taxon data set for angiosperms: the cha]lenges geversmaatsschapplj B. V. Utrecht; velume for 1973- posed by Bayesian analyses of Large data sets. Int. J. 1974 published in i977, Bohn, Scheltemu and Helke- Pl. Sci, 16g: 137-IS7. ma, Utrecht, The Netherlands, Stevens, P. F. 2001 onwards, Angiosperm Phylogeny Oginuma, K., G. Ibara-Manriques & H. Tobe. 1992. Website, ver. 8. http:llxvww.mobot.orglMOBOT,'re- Chromosomes of 7iixtta pittiepi (Astcraceae; Heli- search!A Pweb/' [aceessed Janu ary 26, 2010]. antheae). Acta Phytotax. Geebot, 43: 135-] 37, Takhtajan, A. 2009. Flowering Plants. 2nd edition. Oginuma, K. &H. Tbbe, 1997. Chromosomes ofCaratlia, Springet (]binotroches, and Pellacalyx Received1i'ebruaJv Z 2010,' accqptedApril 8, 20IO NII-Electronic Library Service