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PTEROCERAS MONSOONIAE (ORCHID ACEAE), NEW FROM A INDIA SPECIES and N.Sasidharan P.Sujanapal Kerala Forest Research Institute INTRODUCTION warm Pteroceras Hassk. reported to have 19 species, mostly inhabited in the is humid regions of Southeast Asia, and best represented in Borneo with 10 spe- is From cies (Pedersen 1993). Peninsular India, only one species, Pteroceras & & leopardinum (Parish Reichb. Seidenf. Smitin., reported. During our f.) is Parambikulam recent explorations in the Wildlife Sanctuary of Kerala inter- specimens were The specimens were found esting of Pteroceras collected. to dif- monograph fer from the South Indian species. Following the of the genus known show (Pedersen 1993) the specimens similarities with the Pteroceras little johorense (Holttum) Holttum that seems to be endemic to Johor in Peninsular Malesia. However, they differ in the leaf form and size; texture, form and size of and and the peduncle, size of the bracts floral parts; structure of labellum pol- main linia (Table Pedersen (1993) recognized four types of inflorescences in 1). Our with asperatum PR Hunt, P the genus. species agrees Pteroceras (Schltr) hirsutum (Hook, Holttum, P johorense (Holttum) Holttum, R muriculatum f.) (Reichb. PF Hunt, P philippinense (Ames) Garay and P spathihrachiatum f.) Smith) Garay by having a muricate or prickly (sub)terete rachis without (J.J. who any keel or wings. Drawings of our material were sent to Pedersen sup- new ported our view that should be described and illustrated as a species. it & monsooniae nov Pteroceras Sasidharan Sujanapal, sp. (Fig. l). Type: INDIA. KERALA. PALAKKAD Parambikulam 76-86'552" DISTRICT: Wildlife Sanctuary, I0-32'226" N, E, 1180m, 28 May 2000, P Sujanapal KFRl 30407 (holotype: KFRI; ISOTYPES: BRIT CALI, MH, Pteroceratijohorensi similis in rhachide aculeata tereti et perianthio oblong-ovato acuto vel rotundato, P«roce,=s™„».„i« Character Pterocerasjohorense^ [eaves ca. 5 on a flowering shoot ca.4 on a flowering shoot linear or cm, apex broad, unequally bilobed, ally z^:z:c::r''" mm 4-6 diameter Inflorescence to 3 per plant cm cm Erect, 3.7-4.1 long at right angles to the stem, 1-3 long 2-8,arranged towards the apex 2-4,equidistantly arranged the raceme in cm Epiphytic herb, stem to 2 tall, erect, unbranched. Leaves 4, distichously al- 4-8 ternate, X 1-2 cm, sessile, articulate, linear to elliptic-lanceolate, slightly wider towards the apex, unequally bilobed, lobes rounded; sheaths imbri- leaf cate, glabrous, covering the internodes. Inflorescences racemous, from the ax- cm ils of older leaf sheaths, 2-7, unbranched, at right angles to the stem, 1-3 mm long; peduncle terete, ca. 4 diameter, gray, densely covered with soft brown mm prickles; bracts ca. 6 long, persistent, broadly ovate, spinulose at apex, mm on more prickly abaxial side; base 6 wide, or less sheathing the peduncle; flowers 2-4, sessile, spirally alternating (one open at a time). Sepals and petals on median free, spreading, sparsely prickly abaxial side, grayish-white; sepal column ca. 1.8 X cm, laterals adnate to the foot, elliptic-obovate, apex acute; 1 petals ca. 1.4 x 0.8 cm, oblong-obovate, base rounded, glabrous or slightly mm 4x3 mm, muricate on abaxial side. Labellum to 6 long, side lobes embrac- column and ing the before anthesis spreading (open) after anthesis, apical part widened, apex obliquely rounded, midlobe small, with a porrect spur Spur sac- mm cate, ca. 3 across and 2-toothed at mouth, apex rounded with 2 dorsal ridges. mm mm clinandrium 3 diameter, apiculum 2 long. Anther terminal, triangu- mcumbent, lar with a caudate apex, strongly dehiscing ventrally, to form 2 flaps; mm mm, poUinia obovoid, 1.5-1.8 x deeply stipe 2 long, narrowed cleft, ca. 2, 1 mm towards the base, bilobed at apex, lobes rounded, viscidium obovate, to 1 long, broader than the stipe. Ovary ca. 1 cm, terete, twisted to the left, slightly 6-ribbed, sparsely echinate. Capsule ellipsoid, to 2.8 x cm, 6-ribbed depressed 1.6 apex at (Fig. 1). Note.— The flower has a two-ridged spur with an yellowish neck (like the head of a honey bee) which attracts insects during anthesis. The flowers are ephemeral and withering after 8-10 hours. However, the floral parts continue be attached the ovary during the development. to to fruit Floweringand Fruiting.^May-June, usually flowering with the onset of monsoon. southwest the new Et3'mo logy— Specific epithet of the taxon based on the flowering is Known from Distribution.— only the type locality m Habitat.— This small monopodial epiphyte growing ± 1100 above sea is L on hke Phyllanthus emhlica and Syzygium cumini Skeels along level trees (L.) common the ecotone area of grassland. Other trees in the locality are Cinnamomum sulphuratum Nees, Ficus tinctoria Forst. ssp. parasitica (Koen. f . ex Willd.) Corner, Xantolis tomentosa (Roxb.) Rafin. var ekngioides (DC.) Vajra., The locality constitutes a continuation of the Coimbatore plateau of Deccan etc. which subjected to high velocity of wind and humidity. Therefore the trees is are mostly stunted and clothed with dense moss growth. PARATYPi:: INDIA. Kerala. Palakkad district: Parambikulam Wildlife Sanctuary, 10-32'226" N, 76*86'552" May KFRI 1180 m, 19 2001 Sujanapal 30596 (KFRl). E, ACKNOWLEDGMENTS Our sincere thanks to the Kerala Forest Department (Wildlife) for financial as- sistance. Wildlife Warden and Staff of Parambikulam Wildhfe Sanctuary for We the help rendered during the study. are also thankful to C. Sathish Kumar, TBGRI, Thiruvananthapuram providing and comments, for literature critical Denmark comment- Henrik /Erenlund Pedersen, University of Copenhagen, lor ing on our material, Veldkamp, Rijksherbarium the Latin diagnosis, and J.F for V.B. Sajeev for the illustration. REFERENCE