Taxonomia integrativa e variação geográfica das espécies neotropicais de Latrodectus do complexo mactans-curacaviensis (Araneae, Theridiidae)

Abstract

The integrated analysis of multiple disciplines might reduce inconsistencies related to the use of only one criterion in delimiting crypitcs species. One of these classical controversies is whether the Latrodectus mactans-curacaviensis complex comprises three species for the Brazilian areas. To elucidate this, this paper discusses, using an integrative approach, whether there are consistent patterns of geographic variation in their distribution in Neotropical areas. Four disciplines were tested: morphology (morphometry, design and coloring patterns, egg sacs), biochemistry (protein profile of eggs), immunology (immunogenic potential poison), natural history (ontogenetic development, feeding behavior). The results point to the existence of two evolutionary lineages, ascribable to the previously described Latrodectus corallinus, expanding its distribution to the Tropical Atlantic and the Caatinga areas and undescribed Latrodectus sp. It was not possible to assign a specific name to the second because of limited or ambiguous information about the complex. This species can be differentiated by an ample set of qualitative and quantitative characters. The morphology allowed us to reaffirm the presence of L. mirabilis for Pradaria area. According to our results, that low latitudes, have warm climates, the temperature seems to influence directly the smaller and lighter specimens. We also found evidence of Latroeggtoxins I, II and III in eggs from Brazil. This research contributing to the formulation of hypotheses about the evolutionary processes by which Neotropical Latrodectus populations might have diverged. We point to the need of further research to understand better the limits of variation in taxonomic characters including other areas of South America.