Aspectos ecológicos de stenocercus caducus (squamata:iguanidae) en fragmentos boscosos en el suroeste de mato grosso, brasil

Stenocercus caducus is a Tropidurinae described for Paraguay, Brazil (Mato Grosso, Mao Grosso do Sul and Para) Bolivia (Beni, Chuquisaca, Cochabamba, La Paz, Santa Cruz, Tarija) and Argentina (Jujuy, Salta). It is apparently few demanding in relation to the habitat since it is found in cerrados, cerradoes, gallery forests and occasionally in anthropized areas. In this study, we present ecological aspects of S. caducus, sampled in 18 fragments inserted in pastures matrix, in the southwest region of Mato Grosso in the Semideciduous Submontana Seasonal Forest. We collected in the dry and rainy periods between December 2002 to August 2004, through pitfall traps, with sample effort of 9.000 buckets/day. We investigate the population structure, observing the occurrence of adults only in the rainy period and the predominance of young in the dry period. The sexual ratio found was near to 1:1 in both periods, and we don’t found significant differences in the morphometrics patterns between the sexes. When noticed the use of habitat, the specie proved to be general, using both the pasture matrix, inside and edge of the fragment, showing preference for the edge. Regarding to the diet, it was exclusive for arthropods, having ingested a wide range of preys, being the most frequent and numerous the Coleoptera, Hymenoptera (Formicidae) and Isoptera orders. The apparent plasticity of the species in relation to the use of habitat and diet contributes for its success since it extends the foraging territory and the survivability capacity for the constant anthropic impacts that is transforming the Cerrado areas in a mosaic of fragments.