Diversidade, composição e aspectos da ecologia de taxocenose de serpentes em área serrana de caatinga no nordeste do Brasil

Abstract

Ecologic studies about Caatinga reptiles began in the 1970s, have been intensified in the past two decades, however few of them cover snakes ecology, mainly lato sensu Caatinga. In this context, this work aims to inventory the species and carry out the Taxocenose aspects of ecology of snakes from Serra de Santana, Lagoa Nova, RN. There were semiannual expeditions for 20 consecutive days, in between from March, 2014 and September, 2015. The search and collection of specimens were done through active search along transects, pitfall traps and casual encounters. Throughout effort of 1040 hours.man in search and 3600 days.bucket, 72 specimens belonging to 14 species were registered, with significant presence of Thamnodynastes sp. 2, endemic of Caating and in description phase. The diversity of species was high (H’ = 3.026; index ranges from 1.5 e 3.5), and Oxyrhopus trigeminus, was the most frequent (38.89%). The habitat mostly used was shrubby vegetation (nine species) and the most generalists when it comes to usage of habitat were O. trigeminus, Bothrops erythromelas and Philodryas nattereri. The microhabitats mostly used were sandy soil and earthy ground, and B. erythromelas, P. nattereri and O. trigeminus also confirmed as generalists, and widely seen in different microhabitats. In relation to habits, six species were diurnal, five were nocturnal, and two species of day-and-night habits. High levels of overlap were noticed to habitats, however there was segregation of habitats and periods of activities. The biggest individual found was a female P. nattereri; it was not noticed any sexual dimorphism nor taxocenose. As for foodchain, the diversity of preys was high (H’ = 3.130), and the diet mainly lizards based. There was no correlation between morphometric data and volume and length of preys to any of the species. The results are relevant to support evaluation of ecological aspects barely explored before, specially on possible patterns and/or processes between areas of Caatinga of altitude on Planalto da Borborema (lato sensu) and Depressão Sertaneja Setentrional (stricto sensu).