| Abstract: | The first records on the genus Platypalpus Macquart from Thailand are presented including 10 species new to science: P. fai sp. nov., P. gaemluang sp. nov., P. hualuang sp. nov., P. isaanensis sp. nov., P. nuadkhao sp. nov., P. phomyaaw sp. nov., P. seedam sp. nov., P. seeluang sp. nov., P. siamensis sp. nov., and P. thaicus sp. nov.. A key to these species is provided. All species of Platypalpus known from the Oriental Region (totally 54) are arranged into the species groups currently established for the genus. Eight species groups are recognized from the Oriental Realm and the distribution of each group is briefly discussed. The P. albiseta‐group is most diverse in the Orient with 16 species recorded. Two species of this group possess a modified structure and vestiture of certain abdominal segments that is the first record of this phenomenon in Platypalpus. Also, within the P. albiseta‐group a complex of closely related species sharing an apomorphous condition of the hypoproct has been recognized. In these species the structure of the hypoproct is likely to deal with clasping during copulation instead of the cerci and epandrial lamellae. |
