Taxonomy of Central American water beetles in the genus Hydrochus Leach, 1817 (Coleoptera: Hydrochidae) Author Perkins, Philip D. text Zootaxa 2021 2021-05-21 4974 3 459 503 journal article 6214 10.11646/zootaxa.4974.3.2 5b4eaeb3-5722-4021-84ad-125ccd80855f 1175-5326 4777839 1BD6220B-7540-4A12-B3D2-5EDC1A3B7DD8 Hydrochus steineri Perkins Figs. 1 , 30 Hydrochus steineri Perkins 2020a: 300 . Originally described from Guatemala . Following are new locality data records for Belize, Guatemala and Mexico . Images of the habitus and male genitalia of the holotype , and detailed description of the male genitalia are given in Perkins (2020a) . Material examined (5) : Belize : Stann Creek , Kendal ; ex side pool of Sittee River at bridge, 1.v.1987 , leg. Spangler & Faitoute (1 NMNH ) . Guatemala : Peten , Parque National El Rosario , E of Sayaxche , elev. 145 m ( 16°31’26.9’’N , 90°9’36.32’’W ), 30.vi.2014 , leg. R. S. Zack (3 WSU ) . Mexico : Tabasco , Teapa , 25.v.1974 , leg. M. E. & P. D. Perkins (1 MCZ ) . Differential diagnosis. Among Central American species, recognized by the combination of moderate size (ca. 3.29 mm ), the densely punctate pronotum with deep foveae, the elytra with strial punctures smaller than interstriae, and the male genitalia. This species has a generalized Hydrochus habitus; reliable determinations will require dissection of males. Among the diagnostic features of the male genitalia are the shape of the adbl, the markedly arcuate dorsal surface of the aedeagus where the adbl and shaft meet, the sinuate aedeagus in lateral view, and especially the markedly sinuate ventral margin of the parameres, in lateral view.