Tupistra cardinalis Aver., N. Tanaka & Son, 2018

Averyanov, Leonid V., Tanaka, Noriyuki, Son, Hoang Thanh, Nguyen, Khang Sinh, Maisak, Tatiana V., Nguyen, Tien Hiep & Peng, Ching-I, 2018, Tupistra cardinalis (Asparagaceae), a new species from limestone areas in northern Vietnam, Phytotaxa 334 (1), pp. 60-64 : 60-63

Tupistra cardinalis Aver., N. Tanaka & Son sp. nov. ( Figs. 1 , 2 ).

Diagnosis:— Tupistra cardinalis differs from closest T. longispica by the shorter peduncle, thicker spike, longer perigone tube, filaments not particularly dilated below, anthers attached to the base of perigone segments and larger, hemispheric, dentate stigma.

Type:— VIETNAM, Cao Bang province, Nguyen Binh district, Yen Lac municipality, Chi Doi village, around point 22°45’34”N, 105°51’48.7”E, primary fractionally logged coniferous forest with Pseudotsuga sinensis along highly eroded rocky limestone ridge at elevation about 1400 m a.s.l., ascending terrestrial and lithophytic herb with leaves to 1 m (and more) long on rocky mountain slope, not common, 5 November 2017 (ex hort at the Komarov Botanical Institute, Russia), L. Averyanov & T. Maisak CPC 5429a/ TM 1077/13397 (holotype, LE!, isotypes, LE!). Plants in cultivation were originally collected in the wild at the type locality on 5 October 2013, L. Averyanov, N. T. Hiep, L. M. Tuan, N. S. Khang, T. Maisak, L. Osinovets CPC 5429a.).

Paratype:— VIETNAM, Cao Bang province, Trung Khanh district, Ngoc Con municipality, Trung Khanh nature reserve, around point 22°55’34.3’’N, 106°31’59.3’’E, at elevation about 600 m a.s.l., 19 December 2016, H. T. Son, C. I. Peng, H. C. Lun, K. W. His, CB 3567 (Herbarium of Silviculture Research Institute of Vietnamese Academy of Forest Sciences).

taken by H. T. Son from CB 3567, correction and design by L. Averyanov.

Terrestrial or occasionally lithophytic, evergreen, perennial herb. Roots many, stout, fleshy, white to light grey, hairy. Stems erect, suberect or sometimes ascending, simple or few branched, terete, (3–)4–6(–10) cm long, (2–)2.5–3(–3.5) cm in diameter, covered with sheath leaves and leaf bases, proximally rhizome-like, semi-woody, with many close annular nodes with brownish, partially disintegrated papyraceous bracteal remains. Sheath leaves (cataphylls) equitant, sub-distichous, narrowly triangular or linear lanceolate, base amplexicaule, apex acuminate or acute, (4–)6–25(–30) cm long, (0.5–)1–2(–2.5) cm wide, conduplicate, coriaceous, yellowish-green or light green, glaucous, becoming dark dirty-brown and partially disintegrated with age. Leaves suberect or obliquely expanded, often recurved distally, equitant, (0.8–)1–1.3(–1.5) m long, entire; blade narrowly oblanceolate to oblanceolate, (45–)50–60(–70) cm long, (3–)5–10(–11) cm wide, wavy, leathery, uniformly dark green, glossy, midvein prominently raised abaxially, gradually tapering to thick, rigid, canaliculate, long petiole-like base (35–)45–55(–60) cm long, apex acute to shortly acuminate. Peduncle axillary in apical part of stem, erect, straight or slightly flexuose, fleshy, rigid, subterete, irregularly angled longitudinally, glabrous, (12–)16–18(–20) cm long, as long as or slightly longer than the inflorescence rachis, (5–)6– 8(–10) mm in diameter, whitish, light green, or purplish. Inflorescence a terminal, spadix-like spike, dense or subdense with many flowers, cylindrical, (12–)15–24(–28) cm long, (2.4–)2.8–3.2(–3.5) cm in diameter. Bracts 2 per flower, the outer one larger than the inner one, persistent; the larger one (bract) subtending flower from below, bail-shaped, rectangular to ovate, rigid, fleshy at base, subacute to truncate at apex, slightly irregularly incised and scarious along margins, light green to greenish purple, (7–)8–10(–11) mm long, (4–)4.5–5(–6) mm wide at base, shorter than flowers; the smaller one (bracteole) lateral to flower, oblong ovate, subacute or obtuse, (3–)4–6(–6.5) mm long, ca. 1.5–2 mm wide, purplish, midvein obscurely carinate abaxially. Flower buds obliquely ovoid or (sub)globular, externally dull whitish green tinged with purple. Flowers acropetally open, sessile, patent to slightly ascending, bisexual. Perigone broadly campanulate, distally 6-cleft, (2–)2.2–2.4(–2.6) cm in diameter (perigone with fully recurved segments (1.6–)1.8–2.2(–2.4) cm in diameter), fleshy; proximal tubular part (perigone tube) crateriform, (4.5–)5–6(–6.5) mm long, dull whitish or pale colored on both sides, sometimes tinged purple externally; segments narrowly ovate, irregularly revolute laterally, strongly recurved distally in mid to late anthesis, (8–)9–10(–11) mm long, (4.5–)5–6(–6.5) mm wide at base, pale dull greenish yellow, dull orange yellow tinged green distally, or brownish purple. Stamens 6; filaments inserted at base of perigone segments, shortly subterete, fleshy, 1.4–1.6 mm long, 2–2.2 mm in diameter; anthers ovoid, (1.4–)1.6–1.8(–2) mm long, biloculate, dorsifixed, introrse; pollen whitish. Pistil umbraculate, (10–)11–12(–13) mm long, exceeding perigone; ovary superior, inconspicuous, slightly inflated laterally, (2.8–)3–3.2(–3.4) mm long and wide, glabrous, glossy, white, 3-locular, each locule containing 2 narrowly ovoid ovules; style columnar, straight or slightly curving upward, broadened toward apex, (7–)8–9(–10) mm long, (1.3–)1.4–1.6(–1.8) mm in diameter at base and (2.6–)2.8–3.4(–3.6) mm in diameter in distal part, longitudinally few-ribbed distally, glabrous, white; stigma hemispheric, largely covering anthers, (9–)10–12(–12.5) mm in diameter, frontal surface finely tuberculate, (dark) dull pink purple or dark dull brownish purple, more or less radially striate with darker purple, often irregularly cracked centrally in late stage of flowering, dorsal side whitish, margins revolute, dentate. Fruits and seeds not seen.

Etymology:— The specific epithet refers to the color of the stigmas.

Distribution: —Northern Vietnam: Cao Bang province (Nguyen Binh and Trung Khanh districts). Endemic.

Taxonomic relationships:— Tupistra cardinalis appears closely allied to T. densiflora Aver., N. Tanaka &

Nghiem in Averyanov et al. (2016: 32) described from northern Vietnam in having an umbraculate pistil with a large hemispheric dentate stigma largely covering the anthers, but differs chiefly by the slightly larger (9–12.5 in diameter vs. 6–10 mm in diameter), purplish (vs. white to slightly yellowish) stigma, and significantly longer style (7–10 vs. 3–5 mm).

Tupistra cardinalis may somewhat resemble T. longispica Y. Wan & X.H. Lu in Wan (1984: 168) from Guangxi, China, but is clearly distinguishable mainly by the shorter peduncle (up to 20 cm vs. 20–33 cm), thicker spike (2.4–3.5 cm in diameter vs. 1.5–2 cm in diameter), whitish or pale colored perigone usually with orange yellow or brownish purple segments (vs. white perianth, later turning yellow), longer perigone tube (4.5–6.5 mm vs. 3–4 mm), filaments not particularly dilated below (vs. dilated below), anthers attached to the base (vs. to 1/3 to 1/4 portion above the base) of perigone segments, larger (9–12.5 mm in diameter vs. 5–7 mm in diameter), hemispheric, dentate (vs. peltate, trisected) stigma. It is interesting that Hu et al. (2013; S6-5, Fig. 2G, H ) reported a plant closely resembling T. cardinalis from Guangxi under the name of T. longispica . Further studies on the identity of this Chinese plant are required.

Figures

FIGURE 1. Tupistra cardinalis Aver., N. Tanaka & Son.A. Plant in habitat. B. Flowering plant in habitat. C. Basal part of plant. D. Spike of fully open flowers. E. Portion of spike at late stage of flowering. F. Close up of flowers showing partially cracked stigmas. All photos

FIGURE 2. Tupistra cardinalis Aver., N. Tanaka & Son. (d-EXSICCATES OF VIETNAMESE FLORA 0293/CPC5429a). A. Flowering plants. B. Flattened leaf and inflorescence prior to holotype preparation. C–E. Inflorescences at different stage of anthesis. F. Apical parts of inflorescence with flower buds. G. Flowers in central part of inflorescence. H–J. Flowers, frontal and lateral views. K. Flower bud and floral bracts, lateral view. L. Floral bract and bracteole. M. Removed flowers, frontal views. N. Flowers with removed pistil, frontal and dorsal views. O. Intact individual flower, and flower with removed tepals, lateral views. P. Longitudinal section of apical part of inflorescence showing two flowers. Q. Longitudinal section of flower. R. Stamens and ovary, apical view. S. Stamens, apical and lateral views. T. Pistil, lateral view. U. Pistil, dorsal view. V. Longitudinal section of pistil. W. Stigma, apical view. Holotype and isotypes were prepared from the plants photographed here.All photos taken by L. Averyanov, correction and design by L. Averyanov and T. Maisak.