Corresponding author: Soumya Murugan (
Academic editor: P. de Lange
The new species
Murugan S, Nair MC (2016)
The genus
In Hooker’s Flora of British India,
During the field exploration in the Kollengode range of Nemmara forest division, an interesting
The new species is distinguished from
INDIA. Kerala: Palakkad district, Pothumala, Nelliampathy hills,
Decumbent, unbranched, delicate, succulent herbs attaining 6–10 cm height; the lower portion more or less trailing and bear perennating buds, while the upper portion curves upward and grows erectly. Stem translucent, fleshy, subterete with scattered multicellular and glandular trichomes which form a dense hairy nodal ring. Leaves opposite, fleshy, petiole 0.5–1.5 cm, adaxially grooved, with glandular trichomes; lamina ovate, 1.3–2.5 × 1–1.5 cm, base obtuse, green with pink tinge below, upper surface densely hirsute (0.08–0.09 × 0.03–0.06 cm), lower surface with scattered glandular trichomes (0.02–0.03 cm × 0.03–0.04 cm), margins finely serrate, acute at apex, prominently 3-nerved a pair of nerve obscurely seen near the margin. Inflorescence terminal, unbranched, condensed, a 1–2- flowered cyme. Peduncle more or less absent. Flowers 3-merous, pedicel 0.5–0.7 cm with few glandular trichomes, shorter than hypanthium, light green. Hypanthium 0.8–0.9 cm long, campanulate with scattered glandular trichomes, light green. Calyx lobes 3, 0.15–0.2 cm long, triangular, non-caducous, with sporadic glandular trichomes and pink tinge. Petals 3, 0.8–0.7 × 0.5 cm–0.45 cm orbicular-obovate, acuminate at apex with 3–4 glandular trichomes on the midrib of the abaxial side. Stamens 3; filaments 0.4–0.42 cm long, glabrous, white; anthers yellow, 0.2–0.22 cm, cordate at base, glabrous. Style 0.8–0.9 cm long, curved, deep pink towards the tip, stigma capitate, glabrous. Capsule campanulate, 0.8–0.9 cm long and 0.45 cm wide with occasional glandular trichomes, green. Seeds many, 0.07× 0.02 cm, minutely tuberculed, brown.
October–December.
The specific epithet honours Dr. P.K.K. Nair (1930-), eminent scientist, renowned as father of Indian palynology and founder director of the Environmental Resources Research Centre
Map showing the distribution of
Two populations comprising only a few individuals (5–10) of the species were recorded growing within a distance (50 meters) of each other. Apart from the type locality, the species has yet to be found anywhere else. Because the number of mature individuals is less than 50 and the species has a very restricted area of occupancy, we assign the species, the status of Critically endangered using IUCN Strategies and criteria (
Taxonomic delineation of
Taxonomic traits |
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Habitat | Shady rocks within evergreen forest | Evergreen forests | Riparian forests in high altitudes |
Stem | Decumbent, sub-terete succulent, unbranched with sparse glandular trichomes | Erect, 4-angled, slender, branched with sparse glandular trichomes | Creeping, sub-succulent, branched, glabrous |
Nodal region | Glandular trichomes arranged in a nodal ring | Not prominent | Absent |
Leaf | Petiole 0.5–1.5 cm long, angular, sparsely with glandular hairs; lamina slightly coriaceous, ovate, 1.3–2.5 × 1 –1.5 cm, prominently 3-nerved, an additional pair of nerve obscurely seen near the margin | Petiole 0.4–1.5 cm long; lamina membraneous, narrowly elliptical to ovate, 1–2.5 × 0.4–1.6 cm, Secondary veins 2–3 pairs | Petiole 0.5–1.5 cm; lamina coriaceous, ovate 1- nerved, 2–5 × 1–3 cm |
Nature of hairs on leaf lamina | Dimorphic hairs present, |
Dimorphic hairs present, densely hirsute above and with sparse glandular trichomes below | Absent |
Leaf margin | Narrowly serrate with pink tinge | Serrate without pink tinge | Broadly serrate with pink tinge |
Postion of Inflorescence | Terminal | Terminal | Axillary or terminal |
Inflorescence | Usually 1-2 flowered compressed terminal cyme | Inflorescences occurs at the end of branches, in 1-5 (up to 11-flowered) terminal scorpioid cymes. | Axillary or terminal 5- flowered umbellate cyme |
Peduncle | More or less absent | Up to 2cm, with sparse glandular hairs | 3–4cm long, glabrous |
Pedicel | Pedicel 0.5–0.7cm with sparse glandular trichomes shorter than hypanthium | Pedicel 0.2–0.7cm with sparse glandular trichomes, shorter than hypanthium | Pedicel 1cm long, glabrous, length equalling hypanthium |
Hypanthium | Light green with sparse glandular trichomes | Green with sparse glandular trichomes | Pink, glabrous |
Petals | Petals pink to purple, broadly ovate, slightly clawed on either side,4–5 glandular trichomes on the mid rib below, tip acuminate | Petals pink to purple oblong-elliptic sparse glandular trichomes on the mid rib below, tip acute to acuminate | Petals rose, elliptic, glabrous,tip apiculate. |
Stamen | Anthers half the length of filaments | Anthers as long as filaments | Anthers as long as filaments |
Stigma | Capitate | Three lobed | Capitate |
Capsule | Tubular, 3-sided with sparse glandular trichomes | Tubular, 3-sided with sparse glandular trichomes | Campanulate, glabrous |
The senior author wishes to acknowledge the Kerala State Council for Science Technology and Environment (KSCSTE), Government of Kerala for their financial support by way of its Fellowship in Taxonomy. The authors are thankful to Dr Sasidharan N. (KFRI) and Dr Shaju T (JNTBGRI) for their input into confirming the novelty of