Cymatopus thaicus Grootaert & Meuffels, 2001 Figs. 6–8 Grootaert & Meuffels, 2001: 351 (figs 31–36). Material examined. THAILAND: Andaman Sea: 4 males, Lidi Island, Langu, Satun Province (Andaman Sea), 6°46′56.4″N, 99°45′58.5″E, 30 July 2015, sweep netting, coll. A. Samoh; 12 males, 4 females, Tarutao Island, Langu, Satun Province, 6°44′19.2″N 99°38′45.4″E, 9 January 2015, sweep netting, coll. A. Samoh; 1 male, 1 female, Nang thong beach, 8°39′06.01″N, 98°14′46.60″E, Phang-Nga Province, 5 November 2017, hand collecting on rocks in the sea, leg. P. Grootaert & I. Van de Velde; 6 males, 4 females, Ko Phra Thong, 9°07′33.9″N 98°14′58.5″E, Phang-nga Province, leg. A. Samoh (PSUNHM). NGS barcodes see annexe 1. Diagnosis. A small species (2–2.2 mm) with yellow legs. Fore tibia with a black foliaceous bristle and without an apical spur, but with a long black apical bristle on a short tubercle. Tarsomere 4 dorsally somewhat excavated with long dorsal bristles and as long as the flattened tarsomere 5. Posterior wing border normal, set with equally long hairs. Veins not deformed. Male terminalia as in Fig. 8. Distribution. Thailand, Malaysia and Singapore. The longipilus -group Only one species in Thailand.

Published as part of Samoh, Abdulloh, Satasook, Chutamas & Grootaert, Patrick, 2018, New data on the marine genera Cymatopus Kertèsz and Thambemyia Oldroyd (Insecta, Diptera, Dolichopodidae) from rocky shores in southern Thailand with the description of a new species, pp. 258-267 in Raffles Bulletin of Zoology 66 on pages 262-263, DOI: 10.5281/zenodo.4503124