Diversidade de invertebrados terrestres em cavernas areníticas do estado de São Paulo, com ênfase em Pseudonannolenidae (Diplopoda : spirostreptida)

Abstract

The subterranean fauna from Brazil is the best studied in South America, and most of the publications come from caves in limestone rocks. However, the national territory also includes areas of quartzite rocks, sandstone, granite and iron ore with great speleological potential. Thus, the present study aimed to describe the faunistic composition of arenitic caves in the municipality of Altinópolis state of São Paulo state. We found 131 morphospecies, most of them belonging to Class Insecta (89 morphospecies) and Class Arachnida (31 morphospecies). This fauna corresponds with the fauna found in previous studies in this region and in other studies in the same lithology. The fauna is composed mainly of spiders (Pholcidae, Ctenidae and Sicariidae families), and their possible prey as cockroaches (Blattaria), crickets (Orthoptera), mosquitoes (Diptera), beetles larvae (Coleoptera) and moths (Lepidoptera). In the light reaction tests, the eight taxa studied were significantly photonegative for all light intensities (150, 500 and 1000 lux). Photophobia can be considered a plesiomorphic character state for the group, which is related apparently to the eye patterns (number of ommatidia and ocular area). The Pseudonannolene population from Olho de Cabra cave had low population densities on the four monitoring occasions, with the individuals found mostly in the twilight and aphotic cave zones. The low population density can be attributed to the low concentration of calcium in the soil of the region and, consequently, inside the cave. The effect of seasonality was marginally significant, probably due to the low population density, which may be a consequence of the stress caused by the atypical drought of the last years (2013 and 2014), so that this population is still reestablishing itself. Studies that approach the diversity and biological aspects (e. g. population and behavior) are important to determine relevance of the cave for conservatiom purposes. The present study contributes to the knowledge of the diversity of the subterranean fauna from Altinópolis, and approach the phototactic behavior and population ecology of the subterranean millipede Pseudonannolene never studied before.