Ophiorrhiza trichocarpon Blume (1825: 977)

Hareesh, Vadakkoot Sankaran & Sabu, Mamiyil, 2018, The genus Ophiorrhiza (Rubiaceae) in Andaman and Nicobar Islands, India with a new species, Phytotaxa 383 (3), pp. 259-272 : 269-271

5. Ophiorrhiza trichocarpon Blume (1825: 977) ( Figure 6 )

TYPE:— Indonesis, Java, Linga Jattie and Kambanga Island in shady places, 1823, Blume s.n., (L-0397698!).

Ophiorrhiza hispidula Wall. ex G. Don (1834: 523) .

Type: — Myanmar, Tavoy, 12 May 1827, W. Gomez 1962 ( K 000872538!).

Erect herbs, 5–25 cm tall; stem branched, woody at base, terete, dark purple, densely pubescent; internodes 0.5–4.5 cm long. Stipules linear with a broadened base, margin, acuminate at apex, 2.5–4.5 mm long, acute at apex, pubescent, persistent. Petioles 0.5–4.5 cm long, pale green, pubescent; leaf blades ovate to ovate-lanceolate, 2–10 × 1–4.5 cm, obtuse, acute or acuminate at apex, cuneate at base, adaxially green, glabrous, abaxially pale green, glabrous except the pubescent secondary veins; secondary veins 7–12 pairs. Inflorescence axillary or terminal, corymbose cyme, 2–5 cm in diameter; peduncle up to 1–4 cm long, slender, densely pubescent; bract and bracteoles similar, linear, 0.75–1 mm long, hirsute, persistent. Pedicels c. 1 mm long, hirsute. Flowers 4–5.5 mm long, white. Hypanthium obovoid, 1.75–2 × 1.25– 1.25 mm; disc c. 0.2 mm tall, glabrous. Calyx lobes triangular, 0.5–0.75 × c. 0. 5 mm, pale green, acute at apex, adaxially hirsute, abaxially glabrous. Corolla infundibuliform, 4–6.25 mm long, white, hirsute outside, densely papillose inside with a ring of villous hairs in the middle; lobes ovate-lanceolate, 1.5–2 × 1 mm, slightly curved inwards, acute at apex, shortly keeled on back, spreading. Stamens 3.5–3.75 mm long, inserted just above the base of corolla tube; filaments 2.5–2.75 mm long, white, glabrous; anthers oblong-linear, 0.75–1 mm long, pale yellow; style filiform, 1.75–2 mm long, glabrous; style branches 2, ovate-lanceolate or spathulate,1.5–1.75 × 0.6–0.8 mm, pale green, papillose. Ovary 2-celled, ovules numerous. Capsule obcordate, 1.5–2 × 0.5–0.75 mm long, pale green, hirsute; seeds many, angular.

Distribution, habitat and ecology:— Ophiorrhiza trichocarpon is distributed in Bangladesh, India, Indonesia, Myanmar, Thailand, Malaysia and Java ( Deb & Mondal 1997). In India, it occurs mainly distributed in Andaman and Nicobar Islands, Kerala, Orissa and West Bengal ( Sibi et al. 2012). Similarly to other species of Ophiorrhiza , it also grows in the moist shady places. The intensity of the colour on the dorsal surface of the leaf blade varies from pale green to dark green. The plants growing in less moist shaded areas are less than 5 cm long, where as those growing in more shaded areas or along the sides of water bodies grow up to 25 cm tall.

Specimens examined:— India. Andaman Islands ; North Andaman , Keralapuram, sea level, 21 November 1976, G. N. Nair 4858 ( PBL!) ; Middle Andaman , Camp no. 15, 24 km from Rangat S-W, ± 25 m a.s.l., 03 November 1977, N. Bhargava 6319 ( PBL!) ; Middle Andaman , Billyground, ± 15 m a.s.l., 27 July 1974, N. Bhargava 1974 ( PBL!) ; Middle Andaman , Betapur, ± 15 m a.s.l., 23 July 1974, N. Bhargava 1851/1 ( PBL!) ; Middle Andaman , Ferranrgunj, Bheeheara R. F., ± 150 ft a.s.l., 16 May 2006, R. P. Pandey 26086 ( PBL!) ; South Andaman , near Nilambur, 22 July 1975, N. Bhargava 2479 ( PBL!) ; South Andaman , Rutland Island, near road to camp, 07 April 1978, N. G. Nair 6908 ( PBL!) ; South Andaman , Nayashahr, ± 80 m a.s.l., 12 July 1973, N. P. Balakrishnan 344 ( PBL!) ; South Andaman , Rangachang, sea level, 10 July 1973, N. P. Balakrishnan 277 ( PBL!) ; Little Andaman , Waterfall, ± 80 m a.s.l., 14 August 2004, L. Rasingam 17577 ( PBL!) ; South Andaman , Havelock Island, Peeple Dehra, sea level, 05 September 1977, R. K. Premanath 6145 ( PBL!) ; Little Andaman , Way towards Hut Bay, Digong Creek, 01 September 1976, N. Bhargava 4352 ( PBL!) ; Little Andaman , Near forest Nursery , Hut Bay, Sea level, 08 May 1975, N. Bhargava 2417 ( PBL!) ; Middle Andaman , Betapur, CFO Nallah, near school, 03 August 2017, M. Sabu & V. S. Hareesh 152723 ( CALI!) ; North Andaman , Saddle peak foothill, 06 August 2017, M. Sabu & V. S. Hareesh 152760 ( CALI!) .

Uses:— Ophiorrhiza trichocarpon exhibits camptothecin, an anticancerous drug used for the tratment of cancer ( Sibi et al. 2012).

Relationship of Andaman and Nicobar Islands with the neighbouring areas:— Though part of India, these islands are around 1300 km away from the mainland. The floristic similarity of Andaman group of islands is with that of Indian subcontinent and that of Nicobar islands with Malaysia in the east and Indonesia in the south ( Hajra et al. 1999). Fourteen percent of the angiosperms in the island are endemic, whereas 54% shows similarity with that of mainland India and the remaining 32% extended to the South-East Asian countries and Malaysia. The flora of Andaman differs distinctly with that of Nicobar islands mainly because both these islands are widely separated for about 150 km and ten degree channel. As far as the five species of the genus Ophiorrhiza concerned, O. jojui and O. trichocarpon are restricted to Andaman islands, whereas O. infundibularis , O. nicobarica and O. mungos are restricted to Nicobar islands. Of these, O. jojui , O. infundibularis and O. nicobarica are endemic to the islands.

Figures

FIGURE 6. Ophiorrhiza trichocarpon. A,B. habit. C. a twig with infructescence.D. Split opened corolla showing stamens. E. stigma with style. Photos by M. Sabu & V.S. Hareesh.