The Gyrinidae (Coleoptera) fauna of Thailand: Key to tribes and genera, with new records and keys to species of Dineutini and Gyrinini.

Eighteen species and four genera of the family Gyrinidae are recorded from Thailand. Seven species, belonging to three genera in the tribes Dineutini and Gyrinini, are here treated in detail. Dineutus sitesi Gustafson, Hjek Miller, D. spinosus (Fabricius), D. unidentatus Aub, Porrorhynchus marginatus Laporte and Gyrinus sericeolimbatus Rgimbart were already known, whereas D. australis (Fabricius) and Gyrinus smaragdinus Rgimbart are recorded for the first time. Diagnoses, distribution maps and keys to tribes, genera, and all species of Dineutus and Gyrinus occurring in Thailand are provided. The fourth genus, Patrus (tribe Orectochilini), has been partly revised in a preceding paper.

Review of the Patrus landaisi species group from Thailand with description of three new species (Coleoptera, Gyrinidae).

A survey of the whirligig beetles of the genus Patrus Aubé, 1838 occurring in Thailand belonging to the newly designated Patrus landaisi species group is presented. Three new species are described and illustrated: P. garuda sp. nov., P. nanensis sp. nov. and P. phetchabunensis sp. nov.; with P. apicalis (Régimbart, 1891), P. landaisi (Régimbart, 1892), and P. subapicalis (Ochs, 1930) stat. nov. being recorded for the first time in Thailand. Morphological and molecular analyses, together in an integrative approach, support the elevation of P. subapicalis to species status, instead of being a subspecies of P. apicalis. A diagnosis, illustrations of habitus and diagnostic characters, distribution maps, habitat images and a key to species are provided for all known members of the P. landaisi species group that occur in Thailand. A checklist of species in the group is also given.