Ostryopsis(Mabberley, Crane (1989),On Coryleae (Carpintts

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ISSN OOOI-6799 ActaPhytotax. Geobot. 49 (2): 89-97 (1998)

Phylogenetic Relationships of Betulaceae Based on matKr

Sequences with Particular Reference to the Position of 0str:yopsis

HIDETOSHI KATOi, KAZUO OGINUMA2, ZHIJIAN GU3, BARRY HAMMEL` and HIROSHI TOBE5'

iMakino Uerbarium, 7bkyo Metropolitan Uitiversity, Minami-Osawa, Hbchioji, 7bkyo 192-039Z' 2Flaculty of Human L(fe and Environmentat Sciences, )

Abstract. Relationships among all six genera in Betulaceue, where the position of Osttlyopsts has been uncertain, were investigated on the basis of matK sequence clata. The study includes sequencing of 1260 bases in all six betulaceous genera, Casuarina (Casuarinaceae) and IVbthojbgus (Nothofagaceae), and of 250 bases in ficodendron (Ticodendraceae) lacking in the GenBank data. The maximum parsimony analyses using Nothojirgus as outgroup resulted in a single shortest tree, showing that Betulaceae are

monophyletic with support of 100% bootstrap value and sister to Ticodendraceae.

Betulaceae comprise two well-supported clades as already suggested by earlier cladistic

studies, i,e,, the Alnus-Betula clade and the Carpinus-Ostrya-Corylus-Osttyopsis clade.

Within the latter clacle, Ostryopsis forms a cornmon clade with Coryltts, rather than with the

Carpinus-Ostrya cLade, contrary to results of any of the earlier cladistic analyses,

Molecular evidence from matK sequenee data supports the reeognition of two subfamilies Betuloideae CAInus and Betula) and Coryloideae as in most of the current systems of classification, and furthermore the recpgriition of two tribes Carpnieae (Carpinus and Ostrya) and Coryleae (Corylus and Ostryopsis) in Coryloideae. Morpho]ogical congruency supporting close relatienships between Conylus ancl Ostryopsis is also discussed.

Key words: Betulaceae, Coryloideae, matK, melecular phylogeny, Ostryqpsis, Tlcodendren

Received September 11, l998; accepted December Z 1998

Betulaceae is a well-defined family distributed mainly in the Northern Hemisphere, and comprise about 110 species in six genera Alnus, Betula, Carpinus, Corzylus, Ostrya, and Ostryopsis (Mabberley, 1997). The family has been studied relatively well with respect to generic relationships. Crane (1989), on the basis of a cladistic analysis using 14 morphological and anatomical characters, showed that Betulaceae comprise two monophyletic tribes Betuleae (Alnus and Betuta) and Coryleae (Carpintts, Cocylus, 0strlya, and Ostryopsis), and that within the Coryleae Carpinus and Ostcya are sister taxa, Ostcyopsis sister to the Carpinus-Ostilya clade, and Corylus sister to the Caizpinus-Ostrzya-Ostr:yqpsis clade. Bousquet et

* Author for correspondence

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al. (1992), on the basis of a cladistic analysis of all six genera using 35 morphological, anatomical, and chemical characters, obtained a phylogenetic tree with the same topology as did Crane (1989). Bousquet et al. (1992) further attempted a molecular phylogenetic analysis using rbcL sequence data (not including data from Ostryopsis), and supported the generic relationships shown by the cladistic analysis based on non- molecular data set. Following results of the cladistic or the molecular phylogenetic studies, recent systems of classification mostly divide the Betulaceae into two subfamilies or tribes: Betuloideae or Betuleae (Alnus and Betula) characterized by having male flowers in groups of three, and Coryloideae or Coryleae (Carpinus, Co71ylus, Ostrlya, and Ostryopsis) characterized by having solitary male flowers (Thorne, 1992; Mabberley, 1997). Recently Takhatajan (1997) separated Coryloideae (or Coryleae) as a distinct family Corylaceae from Betulaceae sens. str. (Alntts and Betula), and he divided CoryIaceae into two subfamilies, Carpinoideae (Carpinus, Ostrlya, and Ostryopsis) and Coryloideae (Coryltas). The classification of Takhtajan greatly contrasts to that of Furlow (1990). Furlow (1990, p. 4), like Thorne (1992) and Mabberley (1997), assigned all the six genera to Betulaceae with two subfamilies, Betuloideae and Coryloideae, and he further divided the four genera of Coryloideae into two tribes Carpineae (Carpinus and Ostrya) and Coryleae (Coilylus and Ostryopsis), In order to supplement the molecular phylogenetic analysis of Betulaceae we analysed chloroplast DNA sequences of Ostryopsis, because its phylogenetic position suggested by non-molecular data has never been tested on the basis of molecular data. We also analysed chloroplast DNA sequences of 7'icodendron (Ticodendraceae). Manos and Steele (1997) demonstrated on the basis of matK sequences that, although its sequence data was incomplete, Ticodendron was sister to two examined genera (Betuta and Corytus) of Betulaceae. This paper provides more sequence data for Ticodendron and further confirms that it is never nested within Betulaceae when all the six genera are analysed together. We first sequenced rbcL gene of Ostryqpsis and 71codendron and, by putting their sequence data (accession number in GeneBank ABO15454 and ABO15455) together with the data of the five remaining genera registered in GenBank, analyzed relationships within the family. However, rbcL trees of Betulaceae including Ostryopsis (using 1290 bases and generated by the maximum parsimony method) did not resolve generic relationships within Coryloideae or Coryleae. In fact, a consensus tree of five shortest trees (with length=128, excluding autapomorphies, and CI=O.643) demonstrated that Coryloideae trifurcates into the Carpinus-Ostrya clade, Corylus, and Ostcyqpsis. In other words, in contrast to the cladistic analyses based on the non-molecular data set (Crane, 1989; Bousquet et al., 1992), rbcL sequence data did not clarify relationships withjn Coryloideae or Coryleae. We subsequently analysed matK sequences of all the six genera of Betulaceae and 71codendron, and found that matK sequence data yieids a robust resolution of relationships of CoTlylus and Ostryopsis as well as of

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the relationships among the six genera of Betulaceae and Ticodendron. Concerning the position of Ostilyopsis, the matK tree was different from the tree based on the non-molecular data. This paper presents results of phylogenetic analysis of all the six genera'bf Betulaceae and 71codendron based on matK sequences and show how those and in Ostryopsis are related. On the basis genera particular'the of the results, we will discuss most appropriate infrafamilial classification of Betulaceae.

Materials and Methods

Plant materials One species each of all the six genera of Betulaceae, as well as of AJbthojlagus (N. solandri) selected as outgroup of the family, was studied with respect to chloroplast DNA sequences. Casuarina (Casuarinaceae) and 71codendron (Ticodendraceae) were included in the analysis to "rosid confirm a monophyly of Betulaceae. In rbcL trees of the I" generated by an extensive phylogenetic study of seed plants (Chase et al., 1993, p. 571), Casuarina is positioned nearest to Betula, and Nbthojizgus "higher" more distantly positioned. In the matK trees of Hamamelididae (Manos and Steele, 1997), 1'icodendron is sister to the Betula-Corylus ciade, and Casuarina sister to the Betula-Corylus-Ticodendron clade. All nucleotide sequence data of matK of the six genera of Betulaceae, Casuarina, and IVbthofagus were analyzed, while 250 bases from 526th to 1535th were analysed with respect to 7-icodendron because its matK data from GenBank (accession number U92855) represents only 1010 bases. The eollection data of the species examined and accession numbers in GenBank are presented in Table 1. In order to obtain nucleotide sequence data from fresh leaves, leaf pieces of Alnus, Betula, Carpunus, Corylus, and Ostto?a were collected from wild-growing or. cultivated plants and stored in a freezer controlled at -80 SC. In the case of 0stzyopsis, fresh leaves were preserved in NaCl- CTAB solution (Rogstad, 1992) at room temperature during a period when they were carried out from Kunming to Kyoto. Preserved leaves of Ostilyopsis were rinsed with distilled water in the laboratory and stored in -80OC. the freezer controlled at In the case of ficodendron, collected leaves were dried by silica gel powder in the field and transported to the laboratory.

DNA extraction, amplijicats'on, and sequencing Total DNAs were extracted from the frozen and dried leaves following the modified method of Doyle and Doyle's (1990) using 2 X CTAB extraction buffer. Segments of double-stranded DNA containing most of sequences coding matK gene were amplified using the polymerase chain reaction (PCR). Table 2 and Fig. 1 show the primer designs used in this study. As PCR primers for matK gene, the combination of trnK- 3914F (Johoson and Soltis, 1994) and matK-8R (Ooi et al., 1995) were

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TABLE 1. Taxa studied of Betulaceae and related genera, and theircoUection andDDBIEMBLf GenBank accession number

GenelTaxen Collection Accession number

rbcL

Ostt:yopsis davidiana Decne, Cultivated, Kunming Institute of Botany, ABO15454 Yunnan, Poeple's Republic of China. Z, Gu s, n, ill 1966 (KYO), Ticodendron incognitum COSTA RICA. Heredia, Canton de Barva, ABO15455 Gomez-Laur, & Gomez lidnunel 19433 (MO). matK

Alnus hirsuta Turcz. var. Cultivated, Kamigamo Expetimental Forest ABO15456 sibirica (Fischer) C. K. Station, Kyoto University, Kyoto, Schn. (=A. Ihcana var. Japan, 7bbe 289 (KYO), sibirica Spach) Betula plamphylla Sukaczew Cultivated, Kamigamo Experimental Forest ABO15457 var. faponica (Miq.) Statien, Kyeto University, Kyoto, Hara Japan. Tbbe 310 (KYO). CarpinLcs texijlora (Siebold et Cultivated, Kamigamo Experimental Forest ABe15458 Zucc,) Bl, Station, Kyoto University, Kyoto, Japan. Tbbe 286 (KYO). Corylus americana Walt. Cultivated, Kamigamo Experimental Forest ABO15459 Station, Kyoto University, Kyoto, Japan. 7bbe288 (KYO). Ostrya virginica Willd. Cultivated, Kamigamo Experimental Forest ABO15460 Station, Kyoto University, Kyoto, Japan, Tbbe 290 (KYO), Ostr)Jopsis davidiana Decne. Cultivated, Kunrning Institute of Botany, ABO15461 Yunnan, People's Republic of China. Z. Gu s. n. in 1966 (KYO). Casbcarina eq"isetijblia J. R. Cultivated, Botanic Garden, Osaka City ABO15462 Forst. et G. Forst, University, Kisaichi, Osaka, No voucher, ncodendron incognitum COSTA RICA. Heredia, Canton de Barva. ABO15463 Gomez-Laur, & Gomez Hammel I9433 (MO), IVbthojkegus solandri (Hook.Cultivated, Kamigamo Experimental Forest ABO15464 f.) Oerst. Station, Kyoto University, Kyoto, Japan. 7bbe 311 (KYO).

used. The volume of the amplification reaction mixture was 100pt1, containing 50 ng-100 ng of genomic DNA, 40 pmol of the primer, O.2 mM each of dNTP, 50 mM KCI, 10 mM Tris-HCI pH 8.3, 2 mM MgC12, O.1 % Triton X-100, and 2.0 units of 71iq DNA polymerase (TOYOBO). Amplification was conducted 35 cycles in a DNA thermal cycler. Each eC, cycle consisted of a denaturing step for 1 min at 94 an annealing step for1 min at 50OC, and an extension step for2 min at 72eC. The last OC. extension step was extended up to for 15 min at 72 The amplified DNA fragments were isolated from the remaining primers and dNTPs by using the MicroSpin S-400 HR Columns (Pharmacia). The yield of purified DNA was usually about 5yg, which is enough in amount for five sequencmg reactlons.

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TABLE 2, Location and base composition of amplification and sequencing primers used in this study. Location indicates the start and end nucleotide positions from the start codon relative to the matK ")SeeJohnson (2)See sequence ofAlnus. and Soltis (1994). Ooi etal. (1995).

Primer Sequence Locaiton Strand

trnK-3914F 5'-TGGGTTGCTAACTCAATGG.37 (1) sense matKLAF 5T.CTATATCCACI['IiATCT'ITCAGGAGT-3' (2)428-447674-695963-982 sense matKL03matK-05matK-07matK-8RmatK-04matK-06matK-e8matK-105'-ATTATGTGGCAGATGTAcrAJ37 sense 57-TCCGTAACCAATCTTCIrCATTT-37 sense

5,-ATTATCCAAGCATTCCCTCG-3, senseantlsense 5T.AAAGrCTAGCACAAGAAAGTCGA-3' (2)982-963695-674447428207-188tl 5'-CGAGGGAATGCT'TGGATAAT-3] antlsense 5i-AAATGAGAAGATTGG[ITACGGA-3' antlsense 5'-TAGTACATCTGCCACATAAT-3' annsense 57-ATGAI[TerGTTGATACATTC-3' antasense

trnl > > > > E < < < < < matKLIO matKL08 matKL06 matt

FIG. 1. Diagram showing locatiens of amplification by sequencing primers oi matK used in this $tudy. Arrowheads indicate the direction of strand synthesis. Boxes represent coding regions, .

Nucleotides on purified double-strand DNA were directly sequenced using Thermo Sequenase fluorescent-labelled primer cycle, sequencing kit with 7-deaza-dGTP (Amersham), and an ALF auto-sequencer (Pharmacia) following the manufacturer's instructions. To design a series of primers of matK, we first sequenced nucleotides using matK-AF (sense strand) and matK-8R (antisense strand) (Ooi et aL, 1995) as primers. We were able to read 300 to 400 bases with each of these two primers. The sequences were aligned about several species, and new sense and antiSence primers were designed in conserved areas near the 3' end of the sequence. These new primers were then used to sequence nucleotides subsequent to the 300 to 400 bases; new primers again were designed near the 3' ends of each of these segments. This stepwise process was repeated several times until both strands of nucleotide completely overlap. We sequenced the fragments of both sence and antisence strand to confirm nucleotide sequence. The matK sequences were easily aligned by hand and were found to be varied in length due to the presence of several insertions and deletions. The nucleotide sequence data reported in this paper wi11 appear in the DDBJ!EMBL!GenBank nucleotide sequence databases.

Phylogenetic analysis We employed the maximum parsimony method for phylogeny reconstruction (Fitch, 1977). Nbthojizgus (Nothofagaceae) was used as outgroup to root the trees.

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For the maximum parsimony method, a computer program PAUP" 4,O (Swofford, 1998) was used, and the branch-and-bound search option was applied. AII characters were specified as unweighted. PAUP was also used to perform bootstrap analysis (Felsenstein, 1985) with 1000 replications using the branch-and-bound search option.

Results and Discussion 'IIhe matK gene yielded a matrix of 1260 bases of all the six genera of Betulaceae, Casuarina, and Ticodendron. Insertion of three nucleotides and deletion of six nucleotides were observed in Nbthofizgus solandri, but they were not phylogenetically informative. Sequence variation was observed at 250 (19.8 %) out of the 1260 bases, and 53 (4.2 %) of the 250 bases were phylogenetically informative. Phylogenetic analysis using the maximum parsimony method resulted in a single shortest tree (length==286, excluding autapomorphies; CI==O.818) (Fig. 2). The frequency of homoplasies in the matK tree is much lower than that in the rbcL trees (not shown; the analysis resulted in five shortest trees with a Iength=128, excluding autapomorphies and CI=O.643). The matK tree showed that Betulaceae comprising all six genera Alnus, Betula, Carpinus, Corylus, Ostrya, and Ostr:yqpsis are monophyletic, forming a single common clade supported by 100% bootstrap value. Although our cladogram supports the same separation of these genera into two major clades (Alnus and Betula vs. the others) suggested by Takhtajan (1997), nothing is gained by breaking the traditional Betulaceae into two families. In any case, Takhtajan's distribution of genera into his two subfamilies of Corylaceae is not here supported.

6401o {16) AJnus (1) Betula 1OOe!e Carpinus (10) 1OOe/.(12){4) Betulaceae (6) 1ooef. (4) Ostll}ta 980fo (13) (13) 990!e (2) Cotylus (5) (5> Ostryopsis <25){60>(110) rvcodendron Ticodendraceae Casuarina Casuarinaceae Notholagus Nothofagaceae

RG. 2, A single most parsimonious phylogenetic tree of Betulaceae generated by analyses of matK sequences (1260 bases) using Nothoj1igus as outgroup. Tree length =286; CI==O.818; RI=O.844, Bootstrap values are given above each cLade when they are over 50%, aiid the substitution number of nucleotides below the clade.

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Betulaceae are sister to Ticodendron, A common clade of Betulaceae and 7icodendron was supported by 98 % bootstrap value. The sister-group relationship between Betulaceae and Ticodendron is congruent with results of morphological studies (see articles in the Annats of the MissouTi Botanical Garden 78: 96-151 [1991]). For instance, a very similar type of sieve-element plastids is found in Betulaceae and Ticodendron (Behnke, 1991). Betulaceae are composed of two major clades, one comprising Alnus and Betula, and the other comprising Carpinus, Ostrya, (;brylus, and Ostryopsis. A bootstrap value of the former clade is 64 %, while that of the latter clade is 100 %. The latter clade is further divided into two subclades: the Cacpinus-Ostilya clade and the Corylus-Ostryqpsis clade. Both subclades are supported by high bootstrap values, i.e., 100 % and 99 %. Molecular evidence from matK sequence data thus supports the recognition of Betuloideae (or Betuleae) (Alnus, Beluta) and Coryloideae (or Coryleae) (Carpinus, Corylus, Ostrya, Ostr:yopsis) as in nearly all the earlier infrafamilial taxonomic treatments (e.g., Thorne, 1992; Mabberley, 1997). However, the pattern of generic relationships within Coryloideae does not agree with re'Sults of any of the earlier phylogenetic analyses, where Ostryopsis is considered a sister taxon to the Catzpinus and Ostn}Ja et al. group (seeCrane, 1989;Bousquet , 1992), Ostryqpsis Decne. is a ditypic genus endemic to People's Republic of China, and, because of the lack of the perianth in staminate flowers, has always been placed together with Corytus, Carpinus, and Ostrya in Coryloideae (or Coryleae) (Thorne, 1992; Mabberley, 1997) (or "Corylaceae" Carpinoideae in [Takhtajan, 1997]). In the cladistic analyses by Crane (1989) and Bousquet et al. (1992), Ostryqpsis, like Carpinus and Ostrya, lack the endoaperture in pollen (a synapomorphy). However, as molecular evidence indicates, the lack of the endoaperture in pollen is unlikely to be a synapomorphy indicative of close relationships among Ostryqpsis, Carpinus, and Ostrya. It is rather a homoplasy which had occurred independently in the two groups of genera: once each in Ostryqpsis and a group of Carpinus and Ostrya. Otherwise, the endoaperture might have reappeared in Corylus as reversal after it was Qnce lost in an ancestral clade leading to Carpinus, Corylus, Ostrya and Ostnyqpsis. Looking at a data matrix of morphological characters in "in Bousquet et al. (1992, p. 1078, Table 1), the presence of vessels dentifric pattern," instead of the lack of endoaperture in pollen, is likely to be a synapomorphy linking Ostryqpsis with Corylus, On the other hand, Carpinus and Ostilya share quite a few synapomorphies such as the presence of vessels with at least partially simple perforation (vs exclusively t scalariform perforation), pollen more or less spheroidal with apertures frequently not arranged on the equator (vs various in shape with apertuares equatorial), and ovary composed of two ca.rpels positioned transeverse (vs positioned diagonal) (Bousquet et al.,1992, p. 1078, Table 1). On the basis of results of phylogenetic analyses of matK sequences as well as of reevaluation of morphological characters, we support Furlow

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(1990) who accepted Carpineae comprising Carpinus and Ostrlya and Coryleae comprising Corylus and Ostryqpsis in Coryloideae.

We are grateful to Hiroyuki Tanaka and Hiroshi Okada for their assistance in collecting materials used in this study. '

References

Behnke, H.-D, 1991, Sieve-element characters of 71codendron, Ann. Missouri Bot. Gard, 78: 131-134,

Bousquet, J., S. H. Strauss and P, Li. 1992. Complete congruence between morphological and rbcL-based molecu]ar phylogenies in Birches and related species (Betulaceae). Mol. Biol, Evol, 9: 1076-1088,

Chase, M. W,, D. E. Soltis, R. G, Olmstead, D. Morgan, D. H, Les, B. D. Mishler, M. R. Duvall, R. A. Price, H. G, Hills, Y.-L, Qiu, K, A, Kron, J. H. Rettig, E, Conti, J. D. Palmer, J, R. Manhart, K. J. Sytsma, H. J. Michaels, W. J. Kress, K. G. Karol, W, D, Clark, M, Herdren, B. S. Gaut, R. K. Jansen, K,-J. Kim, C. F. Wimpee, J, F. Smith, G, R. Furnier, S, H, Strauss, Q,-Y, Xiang, G, M, Plunkett, P. S. Soltis, S. M. Swensen, S. E. Williams, P. A, Gadek, C, J, Quinn, L. E. Eguiarte, E. Golenberg, G, H. Learn Jr, S. W, Graham, S. C. H. Barrett, S. Dayanandan and V. A, Albert. 1993. Phylogenetics of seed plants: an analysis of nucleotide sequences from the plastid gene rbcL. Ann. Missouri Bot. Gard. 80: 528-580.

Crane, P. R. 1989. Early fossil history and evolution of the Betulaceae. in P. R, Crane and S. Blackmere (eds.), Evolution, Systematics, and Fossil History of the "Higher Hamamelidae,Volume 2, Hamarnelidae," Systematic Associatien Special Volurne No, 40B: 87-116. Claredon Press, Oxford. Doyle, J. J, and J, L, Deyle. 1990. Isolation of plant DNA from fresh tissue, Focus 12: 13rm15r Felsenstein, J, 1985, Confidence limits on phylogenies: An approach using the bootstrap. Evolution 39: 783-791, Fitch, W, M, 1977. 0n the problem of discovering the most parsimonious tree. Amer. Natur. 111: 223-2S7. Furlow, J, J. 1990. The genera of Betulaceae in the southeastern United States. J, Arnold Arb. 71: 1-67. Johnson, L. A, and D, E, Soltis. 1994, matK DNA sequences and phylogenetic recenstruction in Saxifragaceae sens. str, Syst. Bot, 19: 143-156. Kimura, M. 1981. Estimation ef evolutionary distances b¢ tween homologous nucleotide sequences. Proc. Natl. Acad. Sci. USA 78: 4S4-458. Mabberley, D, J. 1,997. The Plant-Book, 2nd ed, Cambridge University Press, Cambridge. "higher Manos, P, S, and K, P, Steele, 1997, Phylogenetic analyses of Hamamelididae ' based on plastid sequence data, Amer, J, Bot. 84: 14e7-1419, Ooi, K,, Y, Endo, J. Yokoyama and N, Murakarni. 1995, Useful primer designs to amplify DNA fragments of the plastid gene matK from angiesperm plants. J. Jap. Bot. 70: 328-331. Rogstad, S, H. 1992, Satulated NaCl-CTAB solution as a means of field preservation of leaves for DNA analyses. Taxon 41: 701-708. Swofford, D, 1998, PAUP': Phylogenetic analysis using parsimony ("and other methods), version 4.0. Sinauer, Sunderland, MA, Takhtajan, A. 1997. Diversity and Classification of Flowering Plants, Columbia UniveTsity Press, New York, Thorne, R, F. 1992. CIassification and geography of the flowering plants. Bot. Rev, 58: 225-348,

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摘 要

1 2 5 ・ 一 ・ ・ ・ 加 藤 英寿 荻 沼 男 Zhijian Gu3 Barry Hammd4 戸 部 博 ：matK E 伝 子 に よ る カ バ ノ キ科 の 系統解析 ， 特に Ostryopsisの 位置 に つ い て カ バ ノ キ 科 の 全 6 属 の 系 統 関係 を，特 に ま だ 類縁 が 明 らか に さ れ て い な い Ostryopsisを に matK 1260 の よ バ 中心 葉緑 体遺伝 子 （ 塩 基 ） 解析 に り研 究 した 。 解 析 に は カ ノ キ科 6 属 の 他 に ，近 縁 と考 え られ て い る Ticodendron （テ ィ コ デ ン ド ロ ン 科）と モ ク マ オ ウ属 （モ ク マ オ

ウ 科）も加 え，ナ ン キ ョ ク ブ ナ 属 （ナ ン キ ョ ク ブ ナ科 ）を外 群 と し て 最 節 約法 に よ り系統樹 を の バ ー 作 成 した 。 そ 結 果 ， 1 系統 樹 だ けが 得 られ ， 6 属 か ら な る カ ノ キ 科 が 100 ％ ブ トス ト

ラ ッ プ確 率で 支 持 さ れ る 単系 統群 で あ る こ と， カ バ ノ キ 科 は Ticodendron と姉 妹 群 で あ る

こ バ ノ 一 ハ ン とが明 らか に さ れ た 。 また ， カ キ 科 は従 来 般 に考 えれ て きた よ うに ノ キ属 と カ バ ノ キ 属 か ら な る群 （カ バ ノ キ亜 科 ）と シ デ 属， ハ シ バ ミ属 ， ア サ ダ属 ，Ostryopsisの 4 属

か ら な る 群 ハ シ バ ミ 亜 に ら れ こ と も ら か に た か ハ シ バ ミ 亜 の （ 科） 分 け 明 な っ 。 し し ， 科 属 は シ デ 属 と ア サ ダ属 か ら な る シ デ 連 とハ シ バ ミ属 と Ostryopsisか ら な る ハ シ バ ミ連 に分 け

こ で られ ， れ ま 発表 さ れ て きた 分 岐分 類 に よ る 解析結 果 と は 異 な る 結果 が 得 ら れ た 。 こ の 結

果 に基 づ い て ， ハ シ バ ミ 亜 科 を シ デ 属 と ア サ ダ 属 か ら なる シ デ連 とハ シ バ ミ 属 と Ostr）iopsis

か らなる ハ シ バ ミ 連 に 分類 す る Furlow の 見解 を支 持 した 。ま た ，二 つ の 連 そ れ ぞ れ の 共有

つ い 派生 形 質 に て も検討 した 。 1 − − 2 − （〒192 0397 八 王子 市 南 大沢 1 1 東 京都 立 大 学 理 学部 牧野 標本 館 ； 〒 780 8515 高知 女 3 ・ 4 ・ ー 子 大 学 生 活 科 学 部 ： 中 国 中 国 科 学 院 昆 明 植 物 研 究 所 ； 米 国 ミ ズ リ 植 物 園 ； 5 − 〒 606 8501 京都 市左京 区吉 田 二 本松 町 京都 大学 総合 人 間 学 部）

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