Influence of Geographic Distribution on Parasite Loads in Teiid Lizards (Squamata: Ameivula) from Northeastern Brazil

Abstract

The abundance and composition of parasitic faunas are influenced by morphological and environmental characteristics. Environments with distinct climatic characteristics, such as the semiarid Caatinga domain and coastal Restinga ecosystem of Brazil, have particular humidity, rainfall, and temperature conditions that can influence parasitism in lizard communities. We evaluated the effects of geographic distribution and body size on the abundance and composition of endo- and ectoparasites of a lizard species representing each of the habitats: Ameivula ocellifera and A. nigrigula. Body size did not influence parasitic infestations. Both lizard species showed aggregate distribution patterns of the mite Eutrornbicula alfreddugesi. Four endoparasite species were found: Oochoristica, Raillietiella sp., Pharyngodon cesarpintoi, and Physaloptera. The principal endoparasites recorded in A. ocellifera and A. nigrigula were heteroxenous parasites, which are usually indirectly ingested by lizards through their diets (mainly arthropods). The discrepancy indices of endoparasite distributions were similar between the two host species, and showed aggregated distribution patterns. Geographic distributions, substrate temperatures, and the interaction between geographic distribution and air and substrate temperatures influenced ectoparasite abundance in both species, although endoparasite abundance was not explained by these variables. Temperature, precipitation, and humidity during the rainy season in both the Caatinga and Restinga habitats affected parasite abundance, distribution, survival, and development, and contributed to the observed variations in parasitic infestation levels in these lizard species.