Platythyrea janyai, Phengsi, Natthaporn, Jaitrong, Weeyawat, Ruangsittichai, Jiraporn & Salinee Khachonpisitsak,, 2018

Phengsi, Natthaporn, Jaitrong, Weeyawat, Ruangsittichai, Jiraporn & Salinee Khachonpisitsak,, 2018, A sibling species of Platythyreaclypeata Forel, 1911 in southeast Asia (Hymenoptera, Formicidae, Ponerinae), ZooKeys 729, pp. 87-102 : 87-89

Platythyrea janyai sp. n. Figs 1, 5B1-B3

Holotype.

Worker from Southern Thailand, Phatthalung Province, Si Banphot District, Riang Thong Waterfall, Khao Pu Khao Ya National Park, 28.IX.2007, W. Jaitrong leg., Colony no. WJT07-TH-2060 (THNHM-I-02392) deposited in THNHM.

Paratypes.

Three workers, same data as the holotype (THNHM-I-02393 to THNHM-I-02395).

Non-type material examined.

Two workers from Southern Thailand, Trang Province, Na Yong District, Khao Chong Botanical Garden, 7.XI.2014, W. Jaitrong leg., Colony No. WJT071114-2 (THNHM-I-02421 to THNHM-I-02422); one worker from western Malaysia, Selangor, Ulu Gombak, 22.III.2013, F. Ito leg. (THNHM-I-02465).

Measurements and indices.

Holotype.TL 6.63 mm; HL 1.42 mm; HW 1.06 mm; SL 1.39 mm; EL 0.20 mm; WL 2.21 mm; PL 0.73 mm; PH 0.53 mm; PW 0.40 mm; CI 74, EI 18, SI 131. Paratypes (n = 3). TL 6.67-6.96 mm; HL 1.45 mm; HW 1.06 mm; SL 1.42 mm; EL 0.20 mm; WL 2.31 mm; PL 0.79 mm; PH 0.53 mm; PW 0.40 mm; CI 72, EI 18, SI 134.

Worker description.

Head. Head in full-face view subrectangular, clearly longer than broad, with sides weakly convex, occipital corner round, and posterior margin almost straight; antenna relatively long; scape slender, clearly extending beyond posterolateral corner of head; antennal segment II narrow, 1.6 times as long as segment III; III longer than each of segments IV–XII; clypeus broad, in profile with median portion distinctly convex, in full-face view lateral portion narrow and anterior margin clearly convex; mandible triangular, masticatory margin with a large apical tooth, followed by 9-10 smaller teeth, larger and smaller teeth alternating, but the series as a whole decreasing in size toward basal tooth; basal margin of mandible without denticle; eye slightly convex, located laterally anterior to mid-length of head, relatively large, 0.20 mm in maximum diameter, with eleven ommatidia on longest axis, distance between mandibular base and anterior margin of eye 1.5 times as long as maximum eye length; with head in profile, distance between posterior margin of eye and occipital corner of head 3.4 times as long as distance between mandibular base and anterior margin of eye; frontal lobes relatively close to each other, with roundly convex lateral margins; antennal socket horizontal, in plane of transverse axis of head, and in dorsal view, half concealed by frontal lobe.

Mesosoma elongate, in profile with weakly convex dorsal outline; promesonotal suture distinct; metanotal groove absent; mesopleuron not clearly demarcated from mesonotum, but can be separated from metapleuron by a shallow furrow; metapleuron not demarcated from lateral face of propodeum; propodeum with almost straight dorsal outline; propodeal junction rounded; declivity of propodeum shallowly concave; seen from back propodeal declivity tapering above; propodeal spiracle opening elliptical; legs very long.

Petiole cylindrical and sessile, clearly longer than high and broad, its dorsal outline almost straight; with petiole in profile posterodorsal corner with acute angles overhanging declivity of petiole; declivity of petiole shallowly concave; in dorsal view petiole rectangular, its posterior margin concave medially; subpetiolar process weakly developed, subtriangular, located anteroventrally; ventral outline of petiole weakly convex.

Sculpture. Head (including antennal scape), mesosoma, petiole and gaster finely and densely micropunctate; coxae and femora superficially reticulate but shiny.

Pubescence white, very short and fine, distributed over whole body and appendages, longer and more oblique on anterior clypeal margin, tip of mandible and hypopygium; setae absent.

Colouration. Dorsum of head dark brown, while lateral face of head reddish brown; mesosoma, petiole and gaster dark brown to reddish brown (tip of gaster yellowish); antenna and legs yellowish brown (funicular segments paler than scape).

Ecology.

The type series and all material examined of P. janyai were collected from small dead wood on the forest floor in lowland rainforests.

Etymology.

The specific name is dedicated to Mr Janya Jareanrattawong of the Royal Forest Department, Thailand who kindly helped W. Jaitrong in ant collecting in southern Thailand.

Distribution.

Southern Thailand (Phatthalung and Trang Provinces) and western Malaysia.