Tupistra Ker Gawler (1814: 1655) is a genus of the subfamily Nolinoideae (Chase et al. 2009) belonging to the family Asparagaceae (e.g. APG 2009). More than fifty species have hitherto been classified under Tupistra (IPNI 2014), but many of them were recently transferred to Rohdea Roth (1821: 196) by Tanaka (2003a, 2010a). Tupistra, as recircumscribed by Tanaka (2003b, 2010b), is distinguishable from Rohde are defined by Tanaka (2003a, 2010a) by the leaves with more slender petiolar base, relatively larger stigma broader than the style, stouter columnar style almost as thick as the ovary, and usually tuberculate, non-scarlet, spherical berry-like fruit. The species of Tupistra are herbaceous perennials, occurring in the tropical forests of SE Asia including Indochina, where they occasionally form dense local populations. Several studies on karyology (e.g. Yang 1995, Huang & Liu 1996, Hu et al. 2013), breeding system (Qiao et al. 2010), and suitability for food (Nuntayana 2013) have been carried out, but there still are many aspects not satisfactorily investigated, including their taxonomy and phytogeography. Two of us have already described a new species, Tupistra theana Averyanov & Tanaka (2012: 164), from central Vietnam. In the present paper we describe a further new species from northern Vietnam.
FIGURE 1. Tupistra khangii
A. Flowering and fruiting plant. B. Inflorescence. C. Fruits. D. Young portion of inflorescence with flower buds and floral bracts. E. Flower bud and floral bract, side and frontal views. F. Flower, upper and frontal views. G. adaxial aspect of perigone, cut and flattened. H. Flower, sagittal section. Pistil, side view and sagittal section, and frontal and rear views ofstigma at early anthesis (I), at mid anthesis (J), and at late anthesis with transversal section of style (K). L. Transversal section of ovary.
[All drawn by L. Averyanov and T. Maisak from the type – L. Averyanov et al., CPC 7158]
Tupistra khangii Aver., N.Tanaka & N.Vislobokov, sp. nov. (Fig. 1, 2)
Differs from a related species T. longispicaby the white stigma (vs. pale purple stigma), yellow pollen, and the shorter peduncle (vs. peduncle 20–33 cm long).
Type:—NORTHERN VIETNAM. Son La prov., Van Ho distr., Tan Xuan municipality, Cot Moc village, Xuan Nha natural reserve, eastern slopes of Pha Luong Mountain. Broad-leaved evergreen humid forest on very steep mountain slopes as well as on large mossy boulders along narrow shady rocky stream, elev. about 1000 m a.s.l., around point 20°40’33.3’’N, 104°39’00.3’’E. Occasional. 15 November 2013, L. Averyanov, N.T. Hiep, N.S. Khang, N.D. Thang, L.D. Qui CPC 7158(holotype, LE!; isotypes, CPC!).
FIGURE 2. Tupistra khangii
A. Flowering plant in locus classicus (type specimen CPC 7158). B. Flowering plant in natural habitat (CPC 857). C. Portion of inflorescence at early anthesis (CPC 857). D. Portion of inflorescence at late anthesis (CPC 6344). E. Portion of infructescence with ripening fruits (CPC 6344). F. Flowers at early anthesis (CPC 857). G. Flowers at mid anthesis (CPC 7158). H. Flowers at late anthesis (CPC 6344). I. Style and stigma at mid anthesis (CPC 6344). J. Style and splitting stigma toward the end of anthesis (CPC 6344). K. Portion of flower visited by ant (K CPC 857).
[All photos of L. Averyanov and N.S. Khang, image correction and design by L. Averyanov]
Nikolay A. Vislobokov, Maxim S. Nuraliev
Faculty of Biology, M.V. Lomonosov Moscow State University, 1-12, Leninskie Gory, 119234, Moscow, Russia; e-mail: firstname.lastname@example.org
& Joint Russian-Vietnamese Tropical Scientific and Technological Center, Cau Giay District, Ha Noi, Vietnam
98-11, Otsuka, Hachioji, Tokyo 192-0352, Japan
Leonid V. Averyanov
Komarov Botanical Institute, Russian Academy of Science, 2, Prof. Popov Str., 197376, St. Petersburg, Russia
Hiep Tien Nguyen
Center for Plant Conservation, 25/32, lane 191, Lac Long Quan, Nghia Do, Cau Giay District, Ha Noi, Vietnam
Andrey N. Kuznetsov
A.N. Severtsov Institute of Ecology and Evolution of Russian Academy of Sciences, 33, Leninsky Pr., Moscow, Russia