植物研究雑誌 J. J. Jpn. Bo t. 78:269-294(2003) 78:269-294(2003) A New Circumscription of Tadehagi and a New Genus Akschindlium (Leguminosae) Hiroyoshi Hiroyoshi OHASHI Botanical Botanical Garden ，Graduate School of Science ，Tohoku University ，Sendai ，980-0862 JAPAN (Received (Received on April 26 ， 2003) The genus Tadehagi founded by the author in 1973 is revised. It is divided into two genera: genera: Tadeh α gi with a new circumscription and a new genus Akschindlium H.Ohashi based based on Tadehagi godefroyanum (Kuntze) H.Ohashi. Pollen features of three species representing representing the genera Tadehagi ， Akschindlium and Droogmansia 訂 e provided. The newly newly circumscribed Tadehagi is divided into two subgenera: Tadehagi and Kerria. A key key to these genera and subgenera is provided. Tadehagi comprises six species: T. alatum (DC.) (DC.) H.Ohashi ，T. auriculatum (DC.) H.Ohashi ，T. andamanicum (Balakr. & N.G.Nair) S.P.Mathew ，T. robustum Pedley ，T. rodgeri (Schind l.) H.Ohashi and T. triquetrum (L.) H.Ohashi. H.Ohashi. Tadehagi triquetrum varies in the leaf shape and loment hairiness especially in in the Lesser Sunda Islands ，New Guinea and the Philippines. The species is newly cir- cumscribed cumscribed as including subsp. pseudotriquetrum (DC.) H.Ohashi and a hybrid between subsp. subsp. pseudotriquetrum (DC.) H.Ohashi and subsp. triquetrum ， nothosubsp. philippinensis philippinensis H.Ohashi. The hybrid includes a variety ，var. palawanensis H.Ohashi. Tadehagi Tadehagi triquetrum subsp. triquetrum is newly recorded in Taiwan. A key to these spe- cies ，subspecies and hybrids is also provided. Key words: Akschindlium ，Desmodieae ，Droogmansia ，Leguminosae ， Tadehagi. The genus Tadehagi H.Ohashi was estab- calyx ， seeds and bracteoles ， but some charac- lished lished in 1973 based on Pteroloma Desv. ex ters are close to Tadehagi such as the smaller Benth. ， a later homonym of Pteroloma flowers ， narrowly oblong loments with less Hochs t. & Steud. ，and a species of Droog- constricted sutures ， narrowly winged petiole ， mansia De Wild. (Ohashi 1973). It included and pollen morphology. three three subgenera ，i. e. ，Tadehagi s. s甘.， Kerria Pollen grains of Godefroya ，Tadehagi and H.Ohashi ， and Godefroya (Schind l.) H. Droogmansia are fundamentally similar in Ohashi. Ohashi. Tadeh α gi was ，however ， recognized morphology as well as wall stratification. as as intergrade with Droogmansia (Ohashi This overall similarity indicates their close et et al. 1981). This view has been accepted relationship ， but the tectum differs between due to the problematical taxonomic position Droogm α nsia and the other two (Ohashi of of Tadehagi godefroyanum (Kuntze) H. 1971). Godefroya and Tadehagi have reticu- Ohashi ， the monotypic representative of the late to foveolate sculpturing at the subgenus Godefroya (Fig. 1). mesocolpium with the lumina 0.5-1.5 flIIl in Subgenus Godefroya was founded by diameter ， while Droogmansia has reticulate Schindler Schindler (1924) in the genus Droogmansia. sculpturing with lumina 1-3 戸n in diameter It It is similar to Droogmansia in the stamens ， (Figs. 2-4). -269- 270 270 植物研究雑誌第78 巻第5号 平成15 年10 月 In In addition to the similarities in macro- found entirely inside the East Asian distri- scopic scopic and pollen characters between bution range of Tadehagi. Droogmansia is Godefroya Godefroya and Tadehagi ， Godefroya is confined to tropical Africa. Therefore it was Fig. Fig. 1. Akschindlium god ψ， 'oyanum (Kuntze) H.Ohashi. Thailand. Smitinand 10060 (BKF ，cited in Ohashi 1973). October October 2003 Journal of Japanese Botany Vo l. 78 No. 5 271 natural natural to accommodate Godefroya within in any other part of the world (Ohashi 1973 ， Tadehagi Tadehagi (Ohashi 1973). Reassessment of 1992). The genus Dendrolobium is consid- the the morphological and pollen characters as ered to be most primitive genus among outlined outlined above suggested that Godefroya is Desmodium and its related genera and apparently apparently intermediate between Tadehagi Tadehagi ， in the older sense including and and Droogmansia ， in spite of the shared dis- Godefroya ，was supposed to be derived from tribution tribution of the former two genera. Tadehagi Dendrolobium (Ohashi 1973). Dendrolobium and and Droogmansia are recognized as distinct is most abundant in Indochina with several in in results of an analysis of the chloroplast endemic species. Akschindlium and Tade- gene gene rbcL (Bailey et al. 1997 ， Kajita et al. hagi subgenus Kerria are distributed in simi- unpublished) ， although Godefroya is not yet lar areas; the former is restricted to Thailand analyzed. analyzed. The chromosome numbers are and Indochina (Cambodia ， Laos and known only in Tadeh α gi triquetrum subsp. Vietnam) ， and the latter Myanmar ， Thailand triquetrum triquetrum and subsp. pseudotriquetrum ， and Indochina (Laos). Subgenus Tadehagi is i. i. e. ，n = 11 and 2n = 22 (cf. Ohashi 1973 ， widely distributed in SE. and E. Asia and N. Goldblatt Goldblatt and Johnson 1991 ， 1998). Al- Australia ， while Droogmansia is endemic to though though knowledge of these taxa 訂 e insuffi- tropical Africa. It may be supposed that cient cient at the moment ， I would favour Akschindlium and Tadehagi subgenus Kerria recognition recognition of the subgenus Godefroya as an originated in Indochina from a species of independent independent genus distinct from Tadehagi Dendrolobium and that Akschindlium might and and Droogmansi αfor stability of the system be phylogenetically distinct from Droog- of of tribe Desmodieae. To combine these three m αnsza. taxa taxa into one genus would be a revival of the This work had been prepared mainly by wider wider concept of Desmodium proposed by studying herbarium specimens of Tadehagi Bentham (1 865) that is inconsistent in its and its related genera kept in A & GH ，BKF ， boundary boundary with Uraria ，Christia ， or Alysi 国 BO ，CAL ，K ，KYO ，L ，LAE ，NY ，PNH ，TI ， cα rpus. I will discuss the problems in generic TUS ， and US. Studies on the species from circumscription circumscription in the tribe Desmodieae in a Thailand (Ohashi 1982) ， Indo-China (Dy precursory precursory treatment for Desmodium and its Phon et al. 1994) and Malesia (Ohashi in allied allied genera in Malesia (Ohashi in prepara- prep.) were especially helpful for this revi- tion). tion). sion. Field observations were made in The new generic name for Godefroya ， Australia ， China ， the Philippines and Akschindlium Akschindlium H.Ohashi ，is proposed here in Taiwan. Results of pollen mo 叩hology de- honor honor of Dr. Anton Karl Schindler (1 879- scribed in this paper were provided by Ye. 1964) 1964) who founded subgenus Godefroya in Pollen materials were obtained from herbar- Droogmansia and ，also ，made great contribu- ium specimens. Methods used for pollen ex- tions tions to the taxonomy of the tribe amination and terminology for pollen Desmodieae in Leguminosae (see Schubert descriptions in this study 紅 e the same as 1964 ， Pedley 1999). those used in Ye and Ohashi (2002). The tribe Desmodieae is most diverse in the the Sino-Indian region (Ohashi et al. 1981). Pollen morphology Desmodium and its related genera 紅 e con- Pollen grains of Akschindlium ，Droog- sidered sidered to have undergone their prim 紅 y ra- mansia ， and Tadehagi were first described diation diation in SE. Asia because more high level by Ohashi (1 971 ， 1973) using light micros- taxa taxa (genera ， subgenera and sections) of copy. Descriptions and figures 紅 e provided Desmodium and allies occur in this 紅 ea than here from results obtained by scanning elec- 272 植物研究雑誌第78 巻第5号 平成15 年10 月 tron tron microscopy (SEM) and transmission General features of pollen grains of electron electron microscopy (TEM). SEM and TEM Akschindlium ，Droogmansia ， and Tadehagi pollen pollen features in these genera were first (Figs. 2 -4): The pollen grains are tricol 回 shown in Droogmansia scaettaiana by porate; colpi 0.8-0.9 times and endoaperture Ferguson Ferguson and Skvarla (1 981). 0.2-0 .3 times the length of polar axis; exine Fig. Fig. 2. Pollen morphology of Akschindlium god そ斤 oyanum (Schind l.) H.Ohashi. A: Equatorial view. B: Tectum at mesocolpium. C: Equatorial view. D: view. Polar E: Cross section at mesocolpium. F: Cross section. section. G ， H: Cross sections at aperture. Scale bars: A ，C ，D ，F = 5 Il m ，B ，E ，G ，H = 1μm. Voucher specimen: specimen: G. Murata & al. T-37621 (TUS). October October 2003 Journal of Japanese Botany Vo l. 78 No. 5 273 0.8- 1. 5 阿n thick at mesocolpium; tectum ， H.Ohashi (Fig. 2): Pollen grains tricolporate ， infratectum infratectum with foot layer and endexine al- (20.8 一)22.5(-25.6)μm in polar axis ，(2 1. 3一) most most equal in thickness ， each about 1/ 3 of 22.9(-25.0) 伊n in equatorial diameter; P厄= the the exine; columellae regul 訂; foot-layer con- (0.91-) 0.98 (-1. 05) ， oblate spheroidal to tI nuous. prolate spheroidal; colpi broad ， ca. 4 阿n wide wide at equator ，tapering to pointed ends ， Akschindlium Akschindlium god ψoyanum (Kuntze) colpus colpus membrane almost smooth ，occasion- Fig. Fig. 3. Pollen mo 中hology of Droogmansia pteropus (Baker) De Wild. A: Equatorial view. B: Tectum at mesocolpium. mesocolpium. C: Equatorial view. D: Polar view. E: Cross section at mesocolpium. F: Cross section. G: Cross Cross section at aperture. Scale bars: A ，C ，D ，F = 5 ドm ，B ，E ，G ，H = 111m. Voucher specimen: Stolz 2384 (A). 274 274 植物研究雑誌第78 巻第5号 平成15 年 10 月 ally ally with fine granules ， margins almost un- Droogm αnsi α pteropus (Baker) De Wild. differentiated differentiated from mesocolpium; sexine (Fig. 3): Pollen grains tricolporate ，(2 1. 6-) tectate; tectate; sculpture at mesocolpium reticulate 25.3(-27. 1)阿 n in polar axis ，(1 9.5-)2 1. 7 to to foveolate ，occasionally with perforate ， (-23.2) 阿n in equatorial diameter; P厄= lumina lumina 0.5-1.2 阿n in diameter. Exine ca. 1.5 (1. 08-) 1. 17(- 1. 27) ， prolate spheroidal to 阿n thick in mesocolpium ， sexine about as subprolate; colpi broad ， ca.