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 directus Perkins Fig. 2 , 32 Hydrochus directus Perkins 2020a: 295 . Originally described from Guatemala . Following are new locality records for 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 (3) : Mexico : Cotaxtla , Cotaxtla Exp. Sta., 28.vi.1962 , leg. D. H. Janzen (1 CNC ) ; Oaxaca , Tuxtepec ( 31km S), Bethania , Ao. Chopan , 24.v.1981 , leg. Paul J. Spangler (1 NMNH ) ; Veracruz , 9 mi. W. Poza Rica , 27.viii.1965 , leg. Paul J. Spangler (1 NMNH ) . Differential diagnosis. Among Central American species, recognized by the combination of moderate size (ca. 3.00 mm), the densely punctate pronotum with the reliefs slightly less punctate than the depressions, and the male genitalia. This species has a generalized Hydrochus habitus; reliable determinations will require dissection of males. The male genitalia of H. directus is very slender, therefore superficially somewhat similar to that of H. aeruginosus n. sp. ; however, details of the two distinctly differ, including shape and size of the parameres, size and shape of the basal piece, and form of the adbl. The habitus of the two species also distinctively differ.