Histórico do gênero Omophoita (Chrysomelidae, Galerucinae, Alticini) com redescrição de duas espécies

Abstract

Alticini is the most diverse tribe of Chrysomelidae with a large number of species distributed among its almost 600 genera, mainly in the Neotropical region, and for Brazil there are 1,407 species distributed in 142 genera. Despite their diversity, there are still many taxonomic issues to be addressed. Omophoita octoguttata (Fabricius, 1775) and Omophoita personata (Illiger, 1807) are the most important species of the genus. In Alticini it is known that there are a large number of species with taxonomic problems, such as species described more than once because they present different staining pattern, which is used in the differentiation of these two species, besides being sampled in several studies of inventory. The objective of this study is to construct the taxonomic history of the genus Omophoita and to redescribe the O. octoguttata and O. personata species, comparing their external morphology (body, maculae, grooves, ventrites, etc.) and internal morphology (genitals). species as distinct entities. For the construction of the history the original bibliographies of the description of the taxa were consulted. For the construction of the history the original bibliographies of the description of the taxa were consulted. For the morphological study the standard methodology was used for Coleoptera where the specimens were boiled for the softening of the exoskeleton. After genitalia was removed and heated in 10% solution of potassium hydroxide (KOH) for tissue removal. O. octoguttata and O. personata are morphologically similar, but can be distinguished apart from coloration (black elytra with four white maculae in the first and red with six maculae in the second) by: in O. octoguttata apex of the less elongated metasternal process, first ventral with less acute apex, apex of the wider prosternal process, rounded and slightly elevated anterofrontal carina; in O. personata apex of the process of metasterno slightly more elongated; first ventrite with apex that fits in the most acute metasterno; apex of the less elongated prosternal process; narrow, elevated anterofrontal Carina. Therefore, the present study contributed with historical and taxonomic information, which had not yet been evidenced on the genus Omophoita, which shows us the lack of information about the genus and the need for broader studies that find or complement the first steps begun here.