Changing interactions among persistent species as the major driver of seasonal turnover in plant-caterpillar interactions.

ß diversity of herbivorous insects in the tropics is usually very high, and there is often strong dissimilarity in herbivore species composition across different spatial scales and different abiotic gradients. Similarly, turnover is high for trophic interactions between herbivorous insects and their host plants. Two factors have been proposed to explain temporal or spatial differences in trophic interactions: changes in species composition and temporal changes in the behavior of shared species. The goal of this study was to evaluate determinants of high ß diversity of trophic interactions between lepidopteran caterpillars and their host plants across dry and rainy seasons and their transitions. Over the course of a year, interaction diversity data were collected from 275 temporary plots in Cerrado vegetation, comprising 257 species of caterpillars, 137 species of host plants and 503 different trophic interactions. All these diversity parameters varied across seasons. Species assemblages of caterpillars and plants were different among the four seasons, and there was a high turnover of interactions between the seasons. The high temporal ß diversity of trophic interactions was mostly due to interaction rewiring between co-occurring species, as opposed to changes in species composition over time.

Elbella luteizona (Mabille, 1877) (Lepidoptera, Hesperiidae: Pyrginae) in Brazilian Cerrado: larval morphology, diet, and shelter architecture

Abstract This study examined temporal variation in the abundance of immature stages of Elbella luteizona (Hesperiidae) and describes the morphology and behavior of the larvae on their host plants, Byrsonima coccolobifolia and Myrsine guianensis. Five hundred sixty-eight 10 m diameter plots were searched for caterpillars in the Brazilian Cerrado over a period of one year. We inspected 5968 host plants, and found 31 eggs and 262 larvae on 244 plants. Similar numbers of immatures were found in both species of host plants. The abundance of immature stages varied monthly and was significantly higher in the dry season on both host plants, which may be due to the low density of natural enemies during that time. E. luteizona is univoltine, and larvae present relatively little morphological variation. However, during development, substantial changes occur in the architecture of leaf shelters that caterpillars construct. In addition, E. luteizona larvae develop very slowly, taking more than 300 days to complete metamorphosis.

Biology of the immature stages of Strymon crambusa (Lycaenidae, Theclinae) on Oxalidaceae

ABSTRACT We document the biology and morphology of the egg, caterpillar, and pupa of Strymon crambusa (Hewitson, 1874), a Neotropical Eumaeini. In the Cerrado, the caterpillar feeds on the inflorescences and leaves of Oxalis L. S. crambusa has four larval instars, all of which are illustrated. The density of caterpillars on plants is higher than that recorded for leaf-feeding caterpillars and other flower-feeding Eumaeini, which suggests that the species is a specialist on Oxalidaceae in the Cerrado.