Lepidagathis clavata Dalzell (1850: 340)

Kolte, Rutuja Rajendra, Kambale, Sharad Suresh, Gnanasekaran, Gunadayalan & Janarthanam, Malapati Kuppuswamy, 2016, Rediscovery and lectotypification of Lepidagathis clavata (Acanthaceae), a steno-endemic species from the northern Western Ghats, India, Phytotaxa 265 (3), pp. 297-300 : 297-299

Lepidagathis clavata Dalzell (1850: 340) . Fig. 1 .

Lectotype (designated here):― INDIA. Karnataka: Chorla Ghat [as ‘Ghaut’], s.dat., Dalzell s.n. (K000950054, image!). Image is available from http://specimens.kew.org/herbarium/K000950054.

Perennial herb, decumbent, with woody rootstock. Stems 4-angled, with prominent leaf scars at the basal nodes, internodal distances 1–1.3 cm long, glabrous. Leaves sessile, opposite, decussate, rigid, plicate, oblong-lanceolate, 1.7–2 × 0.6–1 cm, truncate at base, entire at margins, spinescent at apex, glabrous; lateral veins 4 or 5 pairs. Inflorescences a spike, solitary, terminal, very rarely branched, 7.5–8 cm long, very compact, oblong or sub-clavate, silky pubescent. Bracts ovate, 1–1.2 × ca. 0.4 cm, attenuate at base, spinescent at apex, 3-veined, silky pubescent. Bracteoles linear-lanceolate, 3-veined. Calyx 5-partite, spinescent at apex, pubescent; outer three ovate-lanceolate, slightly longer than inner; inner two linear-lanceolate. Corolla 1.4–1.8 cm long, rose-pink; tube 0.4–0.5 cm long; upper lip shallowly 2-lobed; lobes broadly ovate, with horizontal pink striations throughout; lower lip distinctly 3-lobed; lobes oblong, glabrous within, hairy without; throat blotched with pale brown to yellowish in the middle with horizontal pink striations along either sides within, blotched with pink spots at gibbous part of the lower lip. Stamens 4, all fertile, didynamous; filaments 3–5 mm long, glabrous, filiform; anthers dehiscing through longitudinal slit. Ovary superior, bi-carpellary, supported on the bowl shaped disc; style 1.2–1.4 cm long, hairy intermixed with stalked glands at the lower half, glabrous otherwise. Capsules ovate, ca. 8 × 3 mm, pointed, glabrous, 2-seeded. Seeds ovoid, ca. 5 × 3 mm, oblique at base, 5-veined, acute at apex, greyish black, covered with golden yellowish hygroscopic hairs.

Phenology:—Flowering and fruiting from January to April.

Habitat:—Open lateritic plateaus at elevations of 810– 850 m.

Distribution:—Endemic to northern Western Ghats, India.

Conservation status: — Lepidagathis clavata is provisionally categorised here as ‘Critically Endangered (CR B1ab (iii) + B2ab (iii))’ according to IUCN Red List Categories and Criteria Version 3.1 ( IUCN, 2012). This species is found in few patches at Chaukul plateau (Amboli) in Maharashtra and Chorla Ghat (Sada) in Karnataka. In addition, it is also observed during the present field exploration that the frequent forest fire and infestation of fresh flowers by an insect lead to low fruit set.

Affinities:— Lepidagathis clavata is closely allied to L. prostrata Dalzell (1850: 138) by having similar corolla and capsule but it greatly differs in it’s habit from the latter.

Local name:—Koch (Marathi).

Additional specimens examined:— INDIA. Maharashtra: Sindhudurg District, Amboli, Chaukul plateau, 850 m, 24 January 2016, Kolte & Kambale 262 ( BSI) ; the same locality, 13 February 2016, Kolte & Kambale 306 ( BSI, MH, SUK) ; Concan, s.dat., Stocks s.n. (CAL0000020087). Karnataka: Belgaum District , Sada , Chorla Ghat , 14 April 2016, Kambale, Kolte & Janarthanam 171 ( Herbarium of Department of Botany in Goa University) .

Figures

FIGURE 1. Lepidagathis clavata Dalzell. A. Habitat (inset: close up). B. Habit. C. & D. Inflorescence. E. & F. Sepals. G. Style: hairy with stalked glands. H. SEM image of pollen grains. I. Seed. J. Seed with golden yellowish hygroscopic hairs. K. Fire burnt plants.