Efeitos de variações ambientais sobre o ajuste ecológico na espécie Gonatodes humeralis (GUICHENOT, 1855) (Squamata: Sphaerodactylideae) no Nordeste brasileiro

Abstract

The study of geographic intraspecific variation aims to understand the natural ability of species to adjust to the environment in which they live. This feat may be particularly observed in species whose range is extensive and comprises a considerable environmental gradient. Recently, the lizard species Gonatodes humeralis (Guichenot, 1855) was recorded in an area of coastal vegetation, on the coast of Ceará. Until then, its distribution was known for Amazonian regions, with occasional occurrences in areas of transition between the Amazon, Cerrado and Caatinga biomes. The coastal areas of the Brazilian Northeast have undergone changes in the landscape throughout its history and the animal populations that live there suffer the impacts directly. We investigated ecological aspects such as body size and temperature, period of activity, use of microhabitats and feeding in a population located in Trairi, northern coast of Ceará, in order to understand its ecological adjustment to a non - Amazon region. In addition, we investigated effects of tree density, number of trunks and fallen branches, and trunk circumference over population density. Gonatodes humeralis, in an area of coastal vegetation, presented reduced body size when compared to Amazonian populations. There is no difference in the period of activity among the populations investigated, but their body temperature varies between localities, as well as habitat exploration. As for diet, the species consumes food resources more generally than in the Amazonian environment. And with respect to the effect of habitat quality on its population density, it was verified that the abundance of the species varies between areas with different levels of conservation, being more abundant in a more conserved area. Our results broaden the understanding of the daily activity, use of the environment and trophic ecology of G. humeralis and contribute to the understanding of the variations in the biological attributes among populations of the same species, besides providing subsidy to the conservation of the coastal habitats of Northeast Brazil.