the second species of verdesmum leguminosae: tribe

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The Second Species of Verdesmum (Leguminosae: Tribe Desmodieae) Found in China

Hiroyoshi ohashia,* and Kazuaki ohashib

a Herbarium, Botanical Garden, Tohoku University, Sendai, 980-0862 JAPAN;b School of Pharmacy, Iwate Medical University, Yahaba, Iwate, 028-3694 JAPAN

*Corresponding author: [email protected]

(Accepted on January 11, 2013)

Hylodesmum menglaense (C. Chen & X. J. Cui) H. Ohashi & R. R. Mill is newly accommodated in Verdesmum as V. menglaense (C. Chen & X. J. Cui) H. Ohashi & K. Ohashi in this paper. This is the second species of Verdesmum belonging to the tribe Desmodieae. The genus is new to the flora of China and the species is endemic to Yunnan.

Key words: Desmodium, Fabaceae, Flora of China, Hanslia, Hylodesmum, Leguminosae, Verdesmum, Verdesmum menglaense, Yunnan.

J. Jpn. Bot. 88: 156–162 (2013)

Hylodesmum menglaense (C. Chen & X. J. Cui) H. Ohashi & R. R. Mill was described by Chen and Cui as Podocarpium menglaense based on specimens collected at Mengla (101°15′E, 21°58′N) in southernmost Yunnan (Cui et al. 1987). The species is distinct from all the other species of Hylodesmum in having linear loments composed of narrowly obovate-elliptic articles of 32–55 mm long with central isthmi between articles (Figs. 1, 2, 3.). Hylodesmum menglaense, on the other hand, similar to Verdesmum hentyi (Verdc.) H. Ohashi & K. Ohashi or Hanslia ormocarpoides (DC.) H. Ohashi in the loments and articles.

Verdesmum hentyi a rare species from Borneo and New Guinea is characteristic in having a funnel-shaped terminal stigma. The genus Verdesmum was established based on characteristics of the stigma unique among the tribe Desmodieae together with such characters as monadelphous stamens, stipitate loments of which the stipe is longer than the pedicel, narrowly obovate-elliptic articles with central

isthmi between articles, broadly triangular lateral calyx-lobes, bracteoles at the base of calyx, and long pedunculate, lax-flowered inflorescences arising from leafless old leaf-axils at base of the stem (Ohashi and Ohashi 2012). The genus relates to Hylodesmum in having monadelphous stamens and in lacking a floral disk around the ovary. However, Verdesmum and Hylodesmum differ in the stigma, loments, articles, bracteoles, inflorescences and shrubby habit. Hylodesmum has a terminal minute capitate stigma, loments with adaxial isthmi between the articles, obliquely semi-circular or broadly semi-obovate articles less than 20 mm long, depressed ovate or elliptic-oblong seeds less than 10 mm long, ebracteolate calyx and herbaceous habit.

Verdesmum hentyi was recognized in Hanslia (Ohashi 2004), because both share stipitate loments of which the articles are narrowly obovate-elliptic with central isthmi. The genus comprises only H. ormocarpoides (DC.) H. Ohashi at present and is distributed in Australia (N. Queensland), Malesia (Lesser Sunda Islands,

June 2013 TheJournal of Japanese Botany Vol. 88 No. 3 157

Fig. 1. Verdesmum menglaense (C. Chen & X. J. Cui) H. Ohashi & K. Ohashi (X. J. Cui & G. D. Tao 84111501, KUN 0419360).

158 植物研究雑誌　第 88巻　第 3号 2013年 6月

Maluku, New Guinea, Philippines and Sulawesi) and Pacific (New Hebrides, Solomon: West Guadalcanal). The species is characteristic in having a lateral stigma, diadelphous stamens, a floral disk and densely flowered, pendulous, terminal inflorescences from the upper stem. Verdesmum is different from Hanslia in having a terminal stigma, monadelphous stamens, lax-flowered, ascending, axillary inflorescences from old leafless axils of leaves on the lower stem and in lacking a floral disk (Ohashi and Ohashi 2012).

The basic characters distinguishing between Hylodesmum, Verdesmum and Hanslia are the shape of the stigma in combination with the monadelphous or diadelphous stamens and the presence or absence of floral disks. Hylodesmum menglaense differs clearly from other species of Hylodesmum in fruits, but flowers of the species have not been described so far. The species is known only from four sheets of herbarium specimens: two type (G. D. Tao 009050, HITBC) (Figs. 4, 5, 6) and two sheets of paratype: (X. J. Cui & G. D. Tao 84111501, KUN). We could not find flowers of the species among these specimens. The images of the types were kindly sent to us by Dr. H. Zhu (HITBC) through Professor H. Sun (KUN) and the paratypes were examined by ourselves in KUN in 2012.

Hylodesmum menglaense is, however, distinguishable from the remaining species of Hylodesmum, Verdesmum hentyi and Hanslia ormocarpoides based mainly on characters of fruits and inflorescences. The following key

indicates distinctions between them:

1. Loments with adaxial isthmi between the articles; articles obliquely semi-circular or broadly semi-obovate less than 20 mm long; herbaceous plants . ............................................ ................. Hylodesmum excl. H. menglaense

1. Loments with central isthmi between the articles; articles narrowly obovate-elliptic, more than 17 mm long; shrubby or subshrubby plants ........................................ 2

2. Inflorescences pendulous, terminal of upper stem with long peduncles, densely many flowered; pedicels 2–4 mm long in fruit, stipe of loments 5–7 mm long, articles 17–20 mm long; terminal leaflet narrowly ovate with rounded base ..... Hanslia ormocarpoides

2. Inflorescences ascending, axillary of basal and medial stem with long peduncles, lax several flowered; pedicels more than 5 mm long in fruit, stipe of loments more than 9 mm long, articles more than ca. 30 mm long ........................................................................ 3

3. Terminal leaflet elliptic with somewhat long cuneate base, pedicels 5–7 mm long in fruit, stipe of loments 9–15 mm long, articles 32–54 mm long ... Hylodesmum menglaense

3. Terminal leaflet broadly ovate with rounded base, pedicels 12–15 mm long in fruit, stipe of loments 15–20 mm long, articles 28–30 mm long .......................... Verdesmum hentyi

Although the correct generic position of Hylodesmum menglaense is insufficiently decided without its flowers, the species is more

Fig. 3. Article (above) and seed (below) of Verdesmum menglaense (KUN 0419360).

Fig. 2. Articles of Verdesmum menglaense (KUN 0419360).


Fig. 4. Holotype of Podocarpium menglaense C. Chen & X. J. Cui (G. D. Tao 009050, HITBC [20113]).Courtesy of Dr. H. Zhu (HITBC) and Prof. H. Sun (KUN).


Fig. 5. Isotype of Podocarpium menglaense C. Chen & X. J. Cui ( G. D. Tao 009050, HITBC [20112]). Courtesy of Dr. H. Zhu (HITBC) and Prof. H. Sun (KUN).


similar to Verdesmum hentyi than other species of Hylodesmum as shown in the key above. Especially H. menglaense and V. hentyi share the same type of inflorescences arising from an old leafless axil of leaf on the old stem, a long loment-stipe and shrubby habit.

Moreover, we noted that Hylodesmum menglaense and Verdesmum hentyi show the same pattern of growth habit. The stems of these species are simple and terminate in a single leafy bud at the axil of the terminal leaf, whereas in Hanslia and the other species of Hylodesmum the stems end in an inflorescence. The same growth habit may support that H. menglaense and Verdesmum hentyi belong to the same genus.

We consider, therefore, that H. menglaense belongs to Verdesmum; hence propose a new combination for the species as follows:

Verdesmum menglaense (C. Chen & X. J. Cui) H. Ohashi & K. Ohashi, comb. nov.

Podocarpium menglaense C. Chen & X. J.

Cui in Acta Bot. Yunnan. 9: 305 (1987). Type: CHINA. Yunnan, Mengla, Menglun, alt. 620 m. 1974 August 6. G. D. Tao 009050 (holo. [20113] & iso. [20112] HITBC).

Desmodium menglaense (C. Chen & X. J. Cui) H. Ohashi in J. Jap. Bot. 70: 142 (1995).

Hylodesmum menglaense (C. Chen & X. J. Cui) H. Ohashi & R. R. Mill in Edinb. J. Bot. 57: 180 (2000); P. H. Huang & H. Ohashi in Z. G. Wu & al., Fl. China 10: 280 (2010).

The type of Podocarpium menglaense is ‘G. D. Tao 009050 (HITBC)’. There are two type specimens, each with a small tag numbered ‘009050’ on the stem. The types are numberd 20112 and 20113, respectively, on the label entitled ‘Flora of China’ (Figs. 4, 5). One of the types numbered 20113 bears an annotation label by Xianju Chui, one of the original authors of the species: ‘Podocarpium menglaense C. Chen et X. J. Chui’, ‘Chui Xianju’ in Chinese characters, and ‘[19]84 November 14’ (Fig. 4). Another type numbered 20112 bears no notes by the original authors of Podocarpium menglaense, but is annotated by X. F. Gao as ‘Typus! Podocarpium menglaense C. Chen et X. J. Chui, 1999 November 8’ (Fig. 5). We regard the former specimen 20113 as holotype, because only this specimen was designated by one of the original authors as Podocarpium menglaense C. Chen & X. J. Chui (Fig. 4). The other type is isotype (Fig. 5).

The holotype shows an inflorescence arising from a leafless old node near the base of the stem and an apex of a branch at the axil of the terminal leaf (Fig. 4). The isotype has many inflorescences one of which bears one young loment (Fig. 5) and separated four articles are included in the packet pasted on the upper left corner of the herbarium sheet (Fig. 6). These inflorescences all seem to arise from the axils of leaves borne near apices of older pieces of stem. No terminal inflorescences are produced in this species, though inflorescences were described as ‘racemes terminal and axillary’ by

Fig. 6. Four articles included in the packet of the isotype of Podocarpium menglaense. Courtesy of Dr. H. Zhu (HITBC) and Prof. H. Sun (KUN).


Huang and Ohashi (2010) in Flora of China. The seeds were described as white in the original description, but one of the collector, G. D. Tao, noted the color as reddish [brown] on one of the paratypes.

We thank Professor H. Sun at Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, for facilitating our studies in KUN and for providing images of the type of Podocarpium menglaense, to Dr. H. Zhu, Curator of the Herbarium, Xishuangbanna Tropical Botanical Garden, for making the images of the type and to Professor S. G. Wu at Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, for helping our herbarium works in KUN and Professor X. Y. Zhu at Botanical Institute, Chinese Academy

of Sciences, Beijing, for assisting us during our studies in PE in August 2012.

ReferencesCui X. J., Chen C. and Wu C. G. 1987. New taxa of the

genus Podocarpium and a new name of Desmodium. Acta Bot. Yunnan. 9(3): 306–308.

Huang P. H. and Ohashi H. 2010. Hylodesmum. In: Wu Z. Y., Raven P. H. and Hong D. Y. (eds.): Flora of China 10: 279–283. Science Press, Beijing and Missouri Botanical Garden Press, St. Louis.

Ohashi H. 2004. Taxonomy and distribution of Desmodium and related genera (Leguminosae) in Malesia (II). J. Jpn. Bot. 79: 155–185.

Ohashi H. and Mill R. R. 2000. Hylodesmum, a new name for Podocarpium (Leguminosae). Edinb. J. Bot. 57: 171–188．

Ohashi H. and Ohashi K. 2012. Verdesmum, a new genus of Leguminosae: tribe Desmodieae. J. Jpn. Bot. 87(5): 299–306.

大橋広好 a，大橋一晶 b：中国雲南産の Verdesmum（マメ科ヌスビトハギ連）第 2 の種　Podocarpium menglaense C. Chen & X. J. Cui は 1987 年に中国雲南省最南部のMengla (101°15′E, 21°58′N)から記載され (Cui et al. 1987)，2000年にヌスビトハギ属として学名を Hylodesmum menglaense (C. Chen & X. J. Cui) H. Ohashi & R. R. Millに組み替えられた (Ohashi and Mill 2000)．この種の標本は現在のところ原記載に引用された 2点（4枚）だけがあり，花は知られていない．Hylodesmum menglaenseは果実と種子の特徴からヌスビトハギ属 Hylodesmumよりも Hansliaに近縁ではないかと考えていたが，花を欠くことで正確に所属を決めることができなかった．一方，2012年にニューギニアとボルネオから記録されていた Hanslia hentyiの花を発見し精査した結果，柱頭がロート状に広がる特徴によってHansliaとは異なることが判明したので，この種に基づいて Verdesmumを記載した (Ohashi and Ohashi 2012)．Verdesmum hentyi (Verdc.) H. Ohashi & K. Ohashiは花部

器官の特異性の他に，茎の基部にある古い節から長い花序を出して，上部にまばらに花をつける特徴をもつことも分かった．この花序特徴は Hylodesmum menglaenseにもみられる．ヌスビトハギ属の中ではオオバヌスビトハギなどにみられる花茎が栄養茎の基部から 1本だけでる様子に似ているが，H. menglaenseでは植物体の下部で木質化した茎の古い節から 1本あるいは複数の花序がでるので，オオバヌスビトハギなどとは異なっている．この点でも Hylodesmum menglaenseとVerdesmumとは共通することから，Hylodesmum menglaenseをVerdesmumに移すこととした．Verdesmum menglaense (C. Chen & X. J. Cui) H. Ohashi & K. Ohashi（新組み合わせ）はこの属の 2番目の種であり，また中国フロラの新しい属である．

（a東北大学植物園津田記念館，b岩手医科大学薬学部）

the second species of verdesmum leguminosae: tribe

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