Species: Patrus apicalis (Régimbart, 1891) Classification Phylum: Arthropoda Class: Insecta Order: Coleoptera Family: Gyrinidae Genus:Patrus Collection specimen Holotype: - Female: Museo Civico di Storia Naturale “Giacomo Doria”, Genova, Italy.
Morphology: Adult: - Patrus apicalis is most similar to P. subapicalis but can be distinguished by P. apicalis male has the mesoventrite with medial pit and the median lobe of the aedeagus with a more needle-like point apex. Females of both species are similar, but the lateral margin of the elytral glabrous region in P. apicalis appears more rounded for 3/4 of its length. The posterior margin of the elytral glabrous region further differs between the two species, having a greater concavity in P. apicalis relative to P. subapicalis. The female of P. apicalis is also similar to that of P. nanensis but can be distinguished by the posterior margin of the elytral glabrous region being more rounded in appearance than that of P. nanensis.
Figure
Habitat: - P. apicalis was found in slow recesses of high elevation streams across the northwestern mountains in Thailand.
Distribution: - Chiang Mai Province: Mae Kam Pong Stream, Mae On District. - Chiang Rai Province: Nam Kuen Stream, Wiang Pa Pao District. - Nan Province: Khun Sathan National Park. - Nan Province: Mae Charim National Park.
Work cited: - Suksai, B., Gustafson, G.T., Sites, R.W. and Sangpradub, N. 2021. Review of the Patrus landaisi species group from Thailand with description of three new species (Coleoptera, Gyrinidae). Zootaxa 4991(3): 561–591.
