Ophiorrhiza, Linnaeus, 1753

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 : 260

Key to the species of Ophiorrhiza in Andaman and Nicobar Islands, India

1. Bract present.......................................................................................................................................................................................2

- Bracts absent....................................................................................................................................................................... O. mungos

2. Bracts 1–2 mm long, calyx lobes subulate, corolla campanulate.......................................................................................................3

- Bracts 3–5 mm long, calyx lobes linear-lanceolate, corolla narrowly infundibuliform................................................ O. nicobarica

3. Calyx, corolla and capsule glabrous or puberulous............................................................................................................................4

- Calyx, corolla and capsule hirsute.............................................................................................................................. O. trichocarpon

4. Leaves ovate-lanceolate, pale yellow beneath (in young and mature stages), stipule persistent, peduncle and pedicel densely pubescent, bracts caducous, short-styled flower with scattered hairs at the base of the corolla tube within, capsule glabrous .......... .................................................................................................................................................................................. O. infundibularis

- Leaves ovate-elliptic, young leaves pale yellow beneath and become dark purple at maturity, stipule caducous, peduncle and pedicel densely pubescent, bracts persistent short-styled flower with a villous ring at the base of the corolla tube within, capsule pubescent .................................................................................................................................................................... O. jojui sp. nov.