Seasonal Variation of the Community of Chrysomelidae (Coleoptera) in a Temperate Forest at Tamaulipas, Mexico

Seasonal variation and its effect on structure and composition of a Coleoptera community were studied, prompted by fragmentation of land cover in natural areas. Some groups of phytophagous beetles are most abundant during the rainy season, although this contrasts with a greater number of community attributes in the season with less precipitation. The hypothesis of our study was that most chrysomelid specimens and species would be observed at the end of the dry season and beginning of the rainy season, with subfamilies Galerucinae, Eumolpinae, and Cassidinae frequent between seasons. The objective was to analyze seasonal variation of Chrysomelidae in a fragment of temperate forest in northwestern Mexico. A sweep net was used in the understory to capture specimens in quadrants. Specimens captured were in six subfamilies, 24 genera, and 31 species, which varied between dry and rainy seasons. Estimated richness was less at the beginning of the rainy season, which was reflected by the greatest percentage of complementarity, although species were present throughout a season. The greatest dominance of Chrysomelidae was in the rainy season, and largest entropy values at the end of both seasons, while diversity of abundant and dominant species was notable at the end of the dry season. Correspondence analysis revealed three faunal associations, indicating the largest number of species was associated with the end of the dry season and beginning of the rainy season, showing precipitation and ambient temperature were most important variables. The community structure between seasons differed, showing that seasonality provided a wide food resource over time, which generated variation in relative abundance and therefore in composition of chrysomelid species. Results suggested temperature variation and water availability determined establishment of Chrysomelidae among months of the year.