Saturday, July 16, 2016

[Botany • 2016] Podochilus warnagalensis • A New Species of Podochilus Blume (Orchidaceae: Epidendroideae) from Adam's Peak, Sri Lanka

Podochilus warnagalensis 
Wijewardana, Priyadarshana, Arangala, Atthanagoda, Samarakoon & Kumar

A new species, Podochilus warnagalensis is described from Adam's Peak Nature Reserve, Sri Lanka. A key to all species of the genus Podochilus found in Sri Lanka is provided.

Keywords: Adam’s peak, biodiversity hotspot, conservation, endemic species, taxonomy, Monocots

FIGURE 1. Podochilus warnagalensis Wijewardana, Priyadarshana, Arangala, Atthanagoda, Samarakoon & Kumar.
A. Plant. B. Front view of inflorescence (purple-white form). C. Lateral view of inflorescence (purple-white form). D. Front view of inflorescence (pink-white form). E. Lateral view of inflorescence (pink-white form). F. Fruit. G. Type-locality (Kuru Ganga/Stream).

Diagnosis:— Podochilus warnagalensis is morphologically close to P. malabaricus; however the new species can be differentiated from the latter on the basis of shorter leaves (0.9–1.0 cm), larger (6–7 mm × 1.2–1.5 mm) completely opened flower, smaller leaves (0.9–1.1 × 0.4 cm), purple coloured peduncle, longer pedicel with ovary (4–4.5 mm ), longer floral bracts (2–2.5 × c. 1 mm), labellum with blunt apex, spur longer and narrower (2.5–3 × 0.8–1 mm) with longer fruit (8–10 mm) in the former in comparison with larger leaves (1.4–1.7 cm), smaller (3.2 x 1.2 mm) incompletely opened flower, longer leaves (1.4–1.7 × 0.5 cm), pale green coloured peduncle, shorter pedicel with ovary (2.2 mm), shorter floral bracts (1.8–2.2 × 1.3–1.4 mm), labellum with pointed apex, short and broad spur (1.5 × 1.2 mm) with shorter fruit (5–6 mm) in latter (see TABLE 1). 

Habitat and Ecology:— Plants grow on lichen and moss covered granite rocks and boulders in streams.  Plants are loosely attached on substrate, expose to almost 100% sunlight.  We observed the species only between Warnagala (6.8269°N, 80.4424°E, 765 m) and Seethagagula (6.8217°N, 80.4575°E, 1061 m) on Adam’s peak, Kuruwita-Erathna foot path, Ratnapura district, Sabaragamuwa province, Sri Lanka (FIGURE 1. G). 

Conservation status:— At present, the new species is known only from the Adam’s peak, Kuruwita-Erathna foot path.  We believe further observation is needed to find out other locality of the species and therefore, yet we suggest the species to be assessed as Data Deficient (DD; IUCN 2012) and endemic to Sri Lanka. 

Etymology:— The specific epithet is based on name of the type locality, Warnagala in Sri Lanka. 

 Ishara H Wijewardana, Tharaka Sudesh Priyadarshana, Nandun S Arangala and Pankaj Kumar. 2016. Podochilus warnagalensis (Orchidaceae), A New Species from Sri Lanka.
Phytotaxa. 266(2);  151 – 156. DOI: 10.11646/phytotaxa.266.2.10