Taxonomy of Guatemalan water beetles in the genus Hydrochus (Coleoptera: Hydrochidae)

The taxonomy of Guatemalan water beetles in the genus Hydrochus Leach, 1817 (Coleoptera: Hydrophiloidea: Hydrochidae) is presented. The known fauna now consists of six species, four of which are described as new species. The new species are diagnosed, and high-resolution images of the habitus and male genitalia of each species are given. The following new species are described: H. directus sp. nov., H. pertuberculatus sp. nov., H. sinuatus sp. nov., and H. steineri sp. nov. The historical types of H. debilis Sharp, 1882 and H. obscurus Sharp, 1882 are redescribed, their lectotypes are designated, and high-resolution images of the habitus, male genitalia and labels of the lectotypes are given.