Tupistra ashihoi D.K.Roy, N.Odyuo & Aver., 2017

Roy, Dilip Kr., Odyuo, N. & Averyanov, Leonid V., 2017, Tupistra ashihoi (Asparagaceae), a new species from north-eastern India, Phytotaxa 305 (1), pp. 52-56 : 52-55

Tupistra ashihoi D.K.Roy, N.Odyuo & Aver. , sp. nov. ( Figs. 1 , 2 )

Differs from T. grandis , T. grandistigma and T. sumatrensis by distinctly petiolate leaves, with wingless petioles, 15–25 cm long, comparatively shorter, elliptic-oblanceolate leaf-blade, to 50 cm long, shorter pistil, 8–9 mm long and in hemispheric, distinctly 6-lobed stigma, to 2 mm thick.

Type:— INDIA. 20 December 2016, D.K. Roy 128909 (holotype, ASSAM!) prepared from a plant cultivated in Garden of Botanical Survey of India, Eastern Regional Centre , Shillong, Meghalaya .

Terrestrial clustering perennial herb, with leaves up to 60 cm high. Rhizomatous stem erect, stout, 1.5–2.0 cm in diameter, nodes dense, covered with remnant bases of sheath-leaves. Roots many, cord-like, thick, fleshy, 4–5 mm in diameter, velutinous. Sheath leaves straight, ensiform, 5–15 cm long, light green. Leaves 2–3, basal, erect, distinctly petiolate; petioles adaxially channelled, 15–25 cm long; leaf blade oblanceolate elliptic, 35–50 × 11–12 cm, shortly acuminate at apex, tapering to the base, lathery, uniform glossy green, with prominent midvein abaxially, secondary lateral veins many, parallel, hardly visible. Peduncle erect, terete, to 14 cm long, arising from apical part of stem, axillary, with no sterile bracts. Spike straight, cylindric, to 22 cm long and to 4 cm in diam., with many flowers; rachis slightly angled longitudinally, fleshy. Bracts 2 per flower, concave, fleshy, light green, slightly tinged with purple; outer bract borne below flower, oblong-ovate, bailshaped, 3–4 × 4.5–5 mm, apex strongly incurved, rounded; inner bract (bracteole) smaller, borne lateral to flower, obovate, 2–2.3 × 2.5–3 mm long, apex slightly upright curved and slightly cucullate. Flowers many, sessile, widely open. Perigone campanulate, 6-cleft, fleshy, dark purple-violet; tube 5–6 mm long; lobes narrowly ovate, 8–9 × 4–6 mm, spreading, straight to slightly incurved, obtuse to acute. Stamens 6; anthers sessile, dorsifixed, narrowly ovoid, introrse, 3 × 1 mm, dull yellowish, attached to the base of perigone lobes below stigma. Pistil 1; style white, columnar, slightly broadening upward, 4.5–5 × 2–2.5 mm, shallowly ridged longitudinally, glabrous; stigma convex to almost hemispheric, 7–8 mm in diameter, to 2 mm thick, white speckled with purple, becoming dark purple after anthesis, shallowly 5–6-lobed at margin, distal lobes broadly triangular, 1–1.5 × 1.5–2 mm; ovary superior, situated at extreme base of columnar pistil, 1.5–2 mm high, 3-locular. Fruit berry-like, subglobose, dark brown, irregularly tuberculate, 0.5–1 cm across, with persistent remnant of the style at apex. Flowering in September–October, fruiting in November–December.

Etymology:—The new species is named in honour of Ashiho A. Mao, Senior Scientist, Botanical Survey of India, Eastern Regional Centre, Shillong, Meghalaya, for his excellent contributions to the Plant taxonomy of north-eastern India.

Distribution:—The new species is currently known only from cultivated specimens in the Garden of Botanical Survey of India, Eastern Regional Centre, Shillong, Meghalaya, India.

Taxonomic relationships:—The comparison of morphology between the known species of Tupistra indicates that T. ashihoi shows similarity to T. grandis , T. grandistigma and T. sumatrensis . The new species differs from T. grandis by distinctly petiolate leaves with wingless petioles, up to 25 cm long (vs. poorly defined petioles up to 40 cm long, with wings), elliptic-oblanceolate leaf blade up to 50 cm long (vs. sublinear, oblanceolate or elliptic, up to 150 cm long), perigone lobes longer than tube (vs. perigone lobes shorter than the tube), anthers located at the base of the perigone lobes (vs. anthers located in the middle of the perigone tube), pistil, 8–9 mm long (vs. 14 mm long), thick, hemispheric, stigma to 2 mm wide, distinctly 6-lobed at margin, purplish white, becoming dark purple after anthesis (vs. thin, peltate, orbicular, obscurely crenulated at margins, white). From T. grandistigma the new species differs by longer spike, to 22 cm long (vs. 16 cm long), 2 bracts per flower (vs. 1), shorter perigone lobes, to 16 mm long (vs. 22 mm long). From T. sumatrensis the described plant differs by shorter spike, to 22 cm long (vs. 35 cm long), shorter perigone, to 16 mm long, with lobes longer than tube (vs. to 30 mm long, with lobes equal the tube), anthers located at the base of the perigone lobes (vs. located in the subbasal portion of perigone tube).

Figures

FIGURE 1. Tupistra ashihoi. A. Habit. B. Inflorescence. C. Basal part of the plant. D. Bract. E. Bracteole. F. Flower. G. Sagittal section of flower. H. Flattened perigone, adaxial surface. I. Perigone lobes. J. Ovary. K. Transversal section of ovary. L. Pistil.

FIGURE 2. Tupistra ashihoi. A. Habit. B. Inflorescence. C. Fruit.