Osbeckia saddlepeakensis Prashob, Manudev, Sibichen & Nampy, Phytotaxa

P., Prashob & Thomas, Sibichen M., 2019, The genus Osbeckia (Melastomataceae) in India, Rheedea 29 (4), pp. 236-305 : 246

Osbeckia saddlepeakensis Prashob, Manudev, Sibichen & Nampy, Phytotaxa 344 (2): 185–190. Type: INDIA, North Andaman Islands , Saddle Peak, 690 m, 29.09.2010, Santhosh Nampy & K.M. Manudev 3526 (holo CAL; iso CALI, DEV, MH).

Fig. 4

Erect, branched, annual herbs, 1.5–8 cm tall. Stems quadrangular, sparsely covered with patent thin hairs, laxly villous. Petioles 1–3 mm long; lamina ovate, 0.5–1.5 × 0.3–1 cm, apex acute, base obtuse, margins ciliate, both sides sparsely clothed with ascending to patent thin hairs, 3-nerved. Inflorescence a terminal short panicle, 3–5- flowered, subtended by 1 or 2 pairs of leaves. Flowers tetramerous, 1–2 mm; pedicels 0.3–1.0 mm long, covered with thin hairs; bracts triangular, 0.3– 0.8 mm long, ciliate. Hypanthium obconic, 1.8–2.5 × 1.5–2.3 mm, sparsely covered with emergences on lower portion, upper portion glabrous. Intersepalar emergences 0.5–1.0 mm long; head stellate with a few long persistent hairs; stalk terete, 0.2–0.5 mm long, glabrous. Other emergences sessile, smaller in size, restricted to lowermost part of hypanthium. Sepals 4, lanceolate, 1.5–2.5 mm long, ciliate, caducous. Petals 4, obovate, 1.5–3.0 × 1–2mm, with few hairs at apex, pink. Stamens 8; filaments 2–2.5 mm long, pink; anthers ovate, 1–2 mm long, glabrous, acute at apex, not twisted; pore single, oblique on dorsal side, connective with conspicuous collar having two small dorsal lobes or tubercles and two ventral lobes. Ovary 4-locular, 1.8– 1.5 mm long, united with hypanthium for about half its length; anther pockets present; crown absent; style 2–4 mm long, glabrous; stigma capitate. Capsules obconic, 4-ribbed, 1.8–2.5 × 1.5–2.3 mm, many seeded; seeds 0.2–0.5 mm long, minute, curved.

Flowering & fruiting: August–November. Habitat: Grows as a forest under growth at elevation between 650–700 m.

Distribution: Endemic to India.

Notes: The species is named after the type locality ‘Saddle Peak’, the highest peak in Andaman and Nicobar Islands. Osbeckia saddlepeakensis is similar to O. muralis and O. brachystemon , but differs by its small flowers (2–4.5 mm across), triangular bracts, obconic hypanthium with emergences on basal portion only, short stalked intersepalar emergences, lanceolate and ciliate sepals and oblong to narrowly ovoid anthers with a single apical pore.

Figures

Fig. 4. OSbeCkia SaddlepeakeNSiS PRaShOb, MaNUdeV, SibiCheN & NaMpy: aa.. Habit; bb.. Petal; CC.. BRaCt; dd.. HypaNthiUM; ee.. CalyX lObe; F. INteRSepalaR eMeRgeNCe; gg.. StaMeN;hh.. Style; ii.. SeedS.