Platythyrea homasawini

Platythyrea homasawini is restricted to highland hill evergreen forests in southern China and Southeast Asia.

Identification
This species is similar to Platythyrea janyai but it can be separated from it by the following characteristics (characters of P. janyai in parentheses unless otherwise stated):
 * 1) head weakly widening anteriorly (head not widening anteriorly)
 * 2) dorsal outline of petiole weakly convex (dorsal outline of petiole almost straight)
 * 3) posterior margin of petiolar node without a concavity in the middle (posterior margin of petiolar node with a concavity in the middle)
 * 4) body surface with thin pubescence (body surface with thick pubescence)
 * 5) head longer (CI = 66 in P. homasawini, CI = 72 in P. janyai)
 * 6) antennal scape relatively long, 1/3 of its length extending beyond posterolateral corner of head (clearly extending beyond posterolateral corner of head)
 * 7) eye smaller and flat (EL = 0.17 mm in P. homasawini; EL = 0.20 mm and slightly convex in P. janyai)
 * 8) seen from back propodeal declivity rounded above (propodeal declivity tapering above)
 * 9) dorsal outline of petiole weakly convex (almost straight)

Platythyrea homasawini can be easily separated from Platythyrea clypeata by the following characteristics (characters of P. clypeata in parentheses unless otherwise stated):
 * 1) head in full-face view, posterior margin weakly concave (posterior margin almost straight)
 * 2) antennal scape relatively long, 1/3 of its length extending beyond posterolateral corner of head (antennal scape short, 1/4 of its length extending beyond posterolateral corner of head)
 * 3) clypeus broad (clypeus narrow)
 * 4) eye larger (EI = 15, with 7 ommatidia in P. homasawini; EI = 11, with 5 ommatidia in P. clypeata)
 * 5) mesosoma relative longer (WL = 2.64 in P. homasawini; WL=1.85–2.05 in P. clypeata)
 * 6) mesopleuron not demarcated from mesonotum (mesopleuron clearly demarcated from mesonotum by shallow furrow)
 * 7) in profile view, propodeal junction roundly convex (propodeal junction obtusely angulate)
 * 8) in dorsal view, posterior margin of petiole clearly con-vex (posterior margin of petiole convex with shallow median concavity)
 * 9) lateral face of head entirely micropunctate (lateral face of head areas behind, above and below eye punctate, with dense foveae)
 * 10) gaster superficially shageened (finely eticulate)

Platythyrea homasawini can be distinguished from Platythyrea gracillima by the following characteristics (characters of P. gracillima in parentheses unless otherwise stated):
 * 1) clypeus roundly convex (rather flat in P. gracillima)
 * 2) petiole laterally convex
 * 3) seen from above longer than high (petiole laterally compressed)
 * 4) seen from above a little more than twice as long as broad
 * 5) mandible finely micropunctate (mandible finely and densely punctate)
 * 6) head entirely finely micopunctate (rather smooth in P. gracillima)

Distribution based on Regional Taxon Lists
Oriental Region: Thailand. Palaearctic Region: China.

Nomenclature

 * . Platythyrea homasawini Jaitrong, Xu & Khachonpisitsak, 2022: 157, figs. 3, 5B1–B3, 7E (w.) THAILAND.

Type Material

 * Holotype worker (THNHM-I-26225), northern Thailand, Chiang ai Prov., Doi Saket Dist., Ban Mae Pong, 24.XI.2021, K. Homasawin leg., Colony No. WJT241121-01.
 * Paratypes: 29 workers (THNHM-I-26226 to THNHM-I-26250, THNHM-I-24977 to THNHM-I-24979, and THNHM-I-26445), same data as holotype.

Taxonomic Notes
This species was reported as Platythyrea clypeata by Xu & Zeng (2000: 214, figs 1–3).