Taxonomic review of the Oriental genus Polyplocia Lestage, 1921 (Ephemeroptera, Euthyplociidae), with two new records for Thailand Author Kwanboon, Sedtawut https://orcid.org/0000-0002-3858-9522 Animal Systematics and Ecology Speciality Research Unit (ASESRU), Department of Zoology, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand Author Boonsoong, Boonsatien https://orcid.org/0000-0002-8166-0021 Animal Systematics and Ecology Speciality Research Unit (ASESRU), Department of Zoology, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand & Biodiversity Center Kasetsart University (BDCKU), Bangkok 10900, Thailand Author Suttinun, Chanaporn https://orcid.org/0000-0002-0380-1554 Department of Veterinary Bioscience and Veterinary Public Health, Faculty of Veterinary Medicine Chiang Mai University, Chiang Mai 50100, Thailand chanaporn.s@cmu.ac.th text ZooKeys 2023 2023-09-11 1179 197 217 http://dx.doi.org/10.3897/zookeys.1179.107312 journal article http://dx.doi.org/10.3897/zookeys.1179.107312 1313-2970-1179-197 9CCA5878F22D4BE9B78BA267F4B3542C 193241E7DFD45606B643A3FABEFE34E7 Polyplocia vitalisi Lestage, 1921 Polyplocia vitalisi Lestage, 1921: 212, original description (male imago). Polyplocia vitalisi ( Ulmer 1939 : 467, figs 7-9, male imago). Polyplocia vitalisi ( Demoulin 1952 : 16, fig. 3, male imago). Polyplocia vitalisi ( Goncalves and Peters 2016 : 558, male imago). Material examined. None. Diagnosis. Imago : i) transparent wing, ii) membrane of forewing with purplish colour on C and Sc fields, iii) abdominal sterna without marking, and vi) penis lobe with a smooth apical border ( Lestage 1921 ). Description. Male imago. See Lestage (1921) . Female imago. Unknown. Nymph. Unknown. Distribution. Tonkin (Vietnam). Remark. This species was described based on one male imago from Tonkin, Vietnam.