História natural de Cassidinae Gyllenhal, 1813 sensu stricto (Coleoptera: Chrysomelidae) na Floresta Nacional de Passa Quatro - MG

Abstract

Cassidinaes. str. is the second largest subfamily in Chrysomelidae (about 3,000 species), with wide diversity in the tropical region, mainly in South America. In Brazil, 1,477 species are described, distributed in 140 genera, 193 of which are recorded in the state of Minas Gerais. Among the characteristics presented by the group, the maternal care, described for 24 species of the subfamily, stands out. Despite the wide diversity recorded for the subfamily, information on the natural history and population dynamics of species of the group is still scarce. Host plants of many species are still unknown. Thus, this study aimed to: (1) survey the fauna of Cassidinaes. str.and (2) describe the natural history and population dynamics of the subsocial species Omaspidesbrunneosignata in its host plant Ipomoea syringifolia (Convolvulaceae). In all, 46 species were recorded, distributed in 23 genera, with 13 new records for the state of Minas Gerais, raising the number of species in the state to 206. Sixty-seven percent of the 46 species occur in other areas of the Atlantic Forest; and 36.9%, 34.8%, 15.2% and 4.3% are recorded for other areas of the Amazon Forest, Cerrado, Pampa and Caatinga, respectively. The identification of the host plant was possible, at least at the family level, for 40 species of cassidines, for nine species the first record was made and for nine species there are 14 new records of host plants. Ecological characteristics such as biology, behavior and natural enemies of some species have been described, including the development time ofimmatures of four species of the genus Stolas. Among the five subsocial species recorded in the reserve, were described the natural history and population dynamics of one of them, Omaspidesbrunneosignata, a bivoltine species, found in the reserve only on the Convolvulaceae Ipomoea syringifolia. Maternal care in the species consists of the physical protection provided by the female and is crucial for the egg stage. The behavior and the natural enemies of the species were recorded. The climatic variables (temperature and precipitation) and leaf density of the host plant did not correlate with the density of adults and immatures of the species. Possible factors influencing population dynamics were discussed.