Sistemática de Ephydrolithus Girón & Short, 2019 (Coleoptera: Hydrophilidae: Acidocerinae)

Abstract

Hydrophilidae Latreille, 1802 is the largest family of beetles with aquatic representatives, encompassing 2,950 species distributed across 172 genera and six subfamilies. Ephydrolithus Girón & Short, 2019, commonly found in hygropetric habitats, belongs to one of these subfamilies, Acidocerinae, which is made up of 23 genera. The objective of this study is to present the first phylogenetic hypothesis for Ephydrolithus, based on morphological characters. In addition to loans of the type material, additional collections were made for other areas and states of Brazil. As a results, two species have been described, including a detailed description of the females' genitalia, and the expansion of the genus's geographical distribution to areas beyond the Serra do Espinhaço, in the Northeast of Brazil, has been documented. The systematic analysis confirmed the monophyly of the genus, and the morphological characters used in constructing the phylogenetic matrix provided crucial details to support the identified clades. This information will contribute significantly to future systematic research on Hydrophilidae, enriching the taxonomic knowledge about the diversity of aquatic insects in the Neotropical Region.