Sonerila sulpheyi P.M.Salim & J.Mathew, 2020

Salim, Pichan M., Mathew, Jose & Hrideek, Thoduvayil K., 2020, Sonerila sulpheyi (Melastomataceae, Sonerileae): A new species from the Southern Western Ghats, India, Phytotaxa 435 (1), pp. 76-80 : 77

Sonerila sulpheyi P.M.Salim & J.Mathew , sp. nov. ( Fig. 1 )

Type:— INDIA. Kerala, Wayanad District, South Wayanad Forest Division, way to Thollayiram Hill region , altitude 1350 m, 13 July 2015, P. M. Salim 2114 (holotype: MH!; isotype: MH!, dried specimen) .

Diagnosis:— Sonerila sulpheyi is similar to S. gadgiliana Ratheesh & Sivadasan (in Ratheesh Narayanan et al. 2015: 10), in morphology and sharing same ecological preferences. It differs mainly in having: glabrescent leaves, petioles, and hypanthia (vs. trichomes on adaxial surface of leaves and sparsely glandular petiole and hypanthia in S. gadgiliana ); ovate leaves with long acuminate apex and unequal leaf bases (vs. cordate leaves with short acuminate apex and symmetric leaf bases); glabrous, compound scorpioid cyme with a terete peduncle (vs. hairy, unbranched scorpiod cyme with quadrangular, caniculated peduncle); glabrous and elliptic petals with short acuminate, green at the apex on the abaxial side (vs. ovate petals with trichomes on the abaxial side and pinkish at the apex on the adaxial side).

Annual succulent herbs 10–20 cm tall. Roots hairy, 1–3 cm long. Tubers small, up to 0.75 cm diameter, creamy in colour. Leaves fleshy, 3–5, glabrous; petiole 1–8.5 cm long, adaxially grooved, glabrous; blade ovate, 2.1–4 × 1.5–2.7 cm, base cordate, with unequal margins, green with pink tinge below, margins finely serrate, long acuminate at apex, prominently 7-nerved, with a pair of obscure nerves near the margin, all nerves are emerging from base. Inflorescence a branched scorpioid cyme, 3–4-branched, 6–14 flowers in each branch. Peduncle cylindrical,, 8–17.5 cm long, glabrous, light green; leafy bracts 0.1–0.3 × ca. 0.1 cm, bracteoles narrow linear, 0.1–0.2 cm long in size. Flowers 3-merous, pedicel 0.4–0.7 cm, light green. Hypanthium campanulate, 0.3–0.6 cm long, light-pink. Calyx lobes 3, triangular, 0.2–0.25 cm long, caducous, glabrous, greenish, and light-pink notched at the base of the calyx. Petals 3, elliptic, mucronate, 0.5–0.7 × 0.3–0.5 cm. Stamens 3; filaments 0.2–0.3 cm long, glabrous, light pink; anthers 0.15– 0.19 cm, glabrous, base cordate, apex acuminate, yellow. Style 0.3–0.4 cm long, straight, dark-pink towards apex. Stigma crowned, glabrous. Fruits a loculicide capsule, campanulate, 0.4–0.8 × ca. 0.3 cm, pinkish-green, polyspermic. Seeds, ca. 0.8 × 0.5 mm, brown, testa tuberculate. Flowering and fruiting in July - September.

Distribution and Habitat:—Found in moist rocks of shola margins at elevations of 1350 m, in Wayanad forests of Western Ghats, India. This species grows in the crevices of rocks and leaf litter in association with Coelogyne breviscapa Lindley (1854: 4) , Plectranthus saxorum J.Mathew, Yohannan & B.J.Conn (2017: 187) , and Medinilla beddomei C.B. Clarke (1879: 548) .

Etymology:—The specific epithet ‘ sulpheyi’ honors Dr. Sulphey M.M. (Prince Sattam bin Abdulaziz University, Saudi Arabia) a renowned educator and environmentalist, in recognition of his valuable contributions to research on pedagogy and ecology.

Conservation status:—The distribution is limited to a few plants at three known locations (each with ca. 25–65 plants). Its area of occupancy is <2 km 2. The threat status of this species has been assigned as Critically Endangered’ (CR 1ab and 2ab) as per the guidelines of IUCN (2012). Moreover, further surveys for this species are suggested.

Notes:—The branched inflorescence of Sonerila sulpheyi is an unusual character in the acaulescent group of Sonerila . This new species is morphologically similar to S. gadgiliana and S. vythiriensis , but it can be readily distinguished from each other (see diagnosis and Table 1.). Sonerila sulpheyi also shares some vegetative morphological similarities with S. coimbatorensis Murugesan, V.Ravichandran & Murugan (2019: 59) , such as the glabrescent plants and pink flowers. Sonerila sulpheyi is readily separated for having 7-nerved leaves (versus 3–5-nerved in S. coimbatorensis ) and 6–14-flowered compound inflorescence (vs. 1–4-flowered simple inflorescence).

Figures

FIGURE 1. Sonerila sulpheyi P.M.Salim & J.Mathew.A. Flowering plant in habitat. B. Uprooted plant. C. Details of root and tubers. D. Detail of tuber. E–H. Details of inflorescence at different angles. I. Abaxial surface of leaf. J. Adaxial surface of leaf. K–L. Detail of petal. M–N. Detail of immature capsules.