Morfologia comparada de espécies do gênero Omophoita Chevrolat, 1837 e Alagoasa Bechyné, 1955 (Coleoptera: Chrysomelidae: Galerucinae: Alticini) da região Sul do Brasil

Abstract

Alagoasa Bechyné, 1955 and Omophoita Chevrolat, 1837 are genera of Coleoptera that are part of the South of Brazil biodiversity. Many species in these genera have been described more than 100 years ago, based primarily on characters that are insufficient for their delimitation, such as color and pattern of maculae in the elytra. These genera frequently are mentioned in biodiversity survey research only identified to the generic level, due to the difficulty in their identification, stemming from the homogeneity of external morphological characters between species. The goal of the present work was to delimit and redescribe, when possible, eleven species of Omophoita and Alagoasa that are similar in their morphology (mainly color and pattern of maculae) and are subject to erroneous identification. Previously identified specimens were studied, loaned from nacional and internacional collections. The morphological analyses were carried out by dissection and observation of the external

structures in a stereomicroscope, as well as microphotographies obtained with photo- stacking equipment. The structures that varied the most, and are considered important

for the specific delimitation, were the reproductive traits, mainly the female genitalia, that are rarely used like distinctive character between species in Alticini. The mouthparts were also informative, especially the characters of the mandible, which allow for separation of the genera. The species in Omophoita formed a more homogeneous group of easier delimitation. Alagoasa species (genus that includes many polymorphic groups), could not be differentiated by the analysis of the reproductive traits alone.