Indigofera tirunelvelica Sanjappa (1983d: 647)

Chauhan, Vibha & Pandey, Arun K., 2015, A revision of trifoliolate Indigofera (Tribe Indigofereae: Fabaceae) in India, Phytotaxa 220 (1), pp. 1-29 : 21

9. Indigofera tirunelvelica Sanjappa (1983d: 647) .

Type:— INDIA. Tamil Nadu: Tirunelveli Dist., along the road side between Kalkad and Sengalteri, 300 m, M. Sanjappa 717 A, December 18, 1980, (holotype CAL!, Isotype 717 B-C, CAL!).

Annual herb, 30–60 cm high; branches erect, biramous hairs adpressed wirh equal arms. Leaves pinnately trifoliolate 3.5–4 cm long; stipules 0.8–1.2 x 0.5 mm, narrowly triangular, adpressed hairy; petioles 1–1.3 cm long, slender, canaliculate above, pubescent; stipellae absent; petiolules c. 1 mm long, pubescent; leaflets (10–) 15–20 (–25) x (5–) 10–15 mm, obovate to narrowly elliptic, cuneate to obtuse at base, rounded and mucronate at apex, biramous hairs adpressed with equal arms on both surfaces, brown punctate gland-dotted beneath. Racemes 5–10 mm long, axillary, sessile; rachis hairy and brown gland-dotted, up to 20-flowered. Flowers pinkish, c. 5 ram long; bracts 1–1.5 x 0.5 mm, ovate, acute, hairy outside, caducous; pedicels c. 1 mm long, hairy, gland-dotted. Calyx adpressed hairy and densely brown gland-dotted outside, cup c. 0.5 mm long, teeth 1–1.5 x 0.5 mm, narrowly triangular. Standard 4–5 x 1.5–2.5 mm, narrowly elliptic, sometimes obovate, mucronate, adpressed strigose and gland-dotted on the back; wing petals 3–4.5 x 1–1.5 mm, glabrous; keel petals 3.5–4.5 x 1.5–2 mm, adpressed strigose and gland-dotted outside, lateral spur 1–1.5 mm long. Staminal sheath 3.5–4 mm long, anthers c. 0.5 mm long. Ovary 1–1.5 mm long, glabrous, 1–2-ovuled; style c. 1.5 mm long, glabrous, glandular towards base. Pods 3–6 x 2–2.5 mm, oblong, flattened, sharply beaked, faintly torulose, 1–2-seeded; upper suture broad; valves prominently veined, adpressed hairy, glandular. Seeds c. 1 x 1 mm, ellipsoid, rounded at on or both ends, reddish-brown, smooth.

Phenology:— Fls. October–December; Frts. November–March.

Distribution:— INDIA: Tamil Nadu (Tirunelveli and Ramanathapuram Dists.); endemic.

Habitat:— Road sides, disturbed and exposed areas in deciduous forests between 300 and 450 m.

Specimen examined:— Tamil Nadu: Tirunelveli Dist., Kalkad to Sengalteri , 1000 ft., February 1913, Hooper & Ramaswami 39230 ; near Tiger Falls, on way to Mancholai , 333 m, 4 March 1959, K. M. Sebastine 5520 ( CAL, MH) ; locality? R. Wight s.n. (Kew Distrib. no. 651) ; Ramanathapuram Dist., Pattanamkathan , 50m, 24 February 1988, V. Balasubramaniam 1673 ( MH) .

Chr. No.:— n = 8 ( Sanjappa 1983).