Bauhinia bassacensis var. nicobarica Tiwari U.L., K. Ravikumar & N. Balachandran, 2013

Tiwari, Umeshkumar, Ravikumar, Kaliamoorthy & Balachandran, Natesan, 2013, A new variety of Bauhinia bassacensis (Leguminosae: Caesalpinioideae) from Great Nicobar Island, India, Phytotaxa 149 (1), pp. 12-18 : 13-16

Bauhinia bassacensis var. nicobarica Tiwari U.L., K. Ravikumar & N. Balachandran , var. nov. ( Figs. 1 & 2 )

Differs from the typical variety in having exstipulate leaves, lobes of leaves obtuse at apex, bract rusty tomentose and ovate, bracteoles 2, lanceolate, rusty tomentose; fertile stamens always 2; filaments hairy, anther lobes brown.

Type :— INDIA. Great Nicobar Island : Near Army land, Campbell Bay, 20 February 2013, N- 71 o 2’ 2.9’’, E 93 o 55’ 2.9’’, 16 m ASL, K . Ravikumar , N . Balachandran and Umeshkumar Tiwari 115533 (holotype FRLH!; isotypes FRLH!, PBL!) .

Large, woody, climbers; tendrils coiled stout, glabrous; young branches rusty tomentose, mature grooved and lenticellate. Leaves exstipulate; petioles glabrescent, 2 7 cm long; lamina ovate-cordate, ca. 19 × 13 cm, 9 13-nerved, bifid, down to 3.5 4.8 cm length with narrow sinus, apex of lobes obtuse, base cordate, upper surface glabrous, lower brownish tomentose to glabrescent, base of the lamina with two distinct glands expanding up to pulvinous base. Inflorescences lateral or terminal, many-flowered, racemes or panicles; peduncles rusty tomentose; pedicels ca. 3.5 cm long in flower and ca. 7 cm long in fruit; bracts ovate, rusty tomentose, ca. 0.5 mm long; bracteoles 2, lanceolate, inserted near the middle of the pedicels, rusty tomentose, 1–1.5 mm long. Buds ovoid, rusty tomentose, 4–6 mm long. Hypanthium c. 1 mm long. Calyx during anthesis splitting into 2 segments forming right angles with the pedicels, 5–7 mm long, sometime persistent with fruit. Petals 2 above and three below, pubescent, creamish with purplish-red veins prominent on both sides, blade deltoid, crumpled, subequal, narrowly ovate to suborbicular with undulate margin, ca. 6 × 5 mm; claw 1.5–2 cm long, soft hairy. Stamens 9 (2 + 7); fertile stamens 2, staminodes absent sometime 1; filaments 1.2–1.6cm long, hairy; anthers 1–2 mm long, lobes brown; reduced stamens 7 in number, unequal, 3–9 mm long, filiform, white. Carpels densely brownish pilose, distinctly stalked, styles 6-8 mm, hairy with a small capitate stigma. Pods rusty tomentose, 8–13 × 3–4 cm with persistent style, stalks c. 3 mm long; styles persistent in fruit. Seeds, 2–5, dark brown, flattened, oblong-orbicular, c. 1.5 × 2 cm, smooth, glabrous.

Flowering & Fruiting:— From February to March.

Distribution:— India: Campbell Bay, Great Nicobar Island, Andaman and Nicobar Islands.

Habitat:— Liana in mixed semi-evergreen forests.

Ecological status:— About three individuals confined to an area of 1 km 2 were observed during field survey. Though it qualifies to be kept under Critically Endangered (CR) category, further studies and explorations in adjacent areas are required to ascertain its actual status.

Etymology:— The varietal epithet refers to the place of its collection.

This new variety is allied to typical var. bassacensis and var. backeri , but differs from both markedly in having exstipulate leaves, lobes of leaves obtuse at apex, bract rusty tomentose and ovate, bracteoles 2, lanceolate, rusty tomentose; fertile stamens always 2; filaments hairy, anther lobes brown (see table 1).

Figures

FIGURE 1. Bauhinia bassacensis var. nicobarica: A. Twig with fruits; B. Inflorescence; C. Petals; D. Bract; E. Bracteoles and F. L. S. of Fruit with Seeds (Drawn after K. Ravikumar et al. 115533 by Umeshkumar Tiwari).

FIGURE 2. Bauhinia bassacensis var. nicobarica: A. Twig with inflorescence; B. Type Specimen 115533 (FRLH); C. Close up of Flower; D. Anthers and filaments and E. Fruits.(Photo plate is prepared by Umeshkumar Tiwari after K. Ravikumar et al. 115533).