Body size, female reproduction and sexual dimorphism in the lizard Ameiva ameiva (Teiidae) in a restinga of southeastern Brazil

Abstract

In this study 57 specimens of the lizard Ameiva ameiva (Linnaeus, 1758) collected in the restinga at Barra de Maricá, in the state of Rio de Janeiro, southeastern Brazil, were analyzed to investigate size relations and reproduction (in females) and sexual dimorphism of this population. We answered the following questions: 1) what is the minimum reproductive body size in females? 2) what is the average clutch size and 3) how is clutch size related to body size? 4) Are body and head sizes sexually dimorphic? Mean clutch size was 6.7 ± 2.1 eggs and was positively correlated with female body size. Sexual dimorphism favoring males was found: adult mean snout-vent length was great in males (124.2 ± 17.8 mm) than females (96.5 ± 23.1 mm SVL), and males were larger with respect to head width and length, and body mass. Thus, despite the marked seasonality at Barra de Maricá, A. ameiva has an extended reproductive period. Also, intrasexual selection may have acted on females to produce larger clutches, and on males, favoring larger males.

A summary of reptile and anuran amphibian species from Brazilian sandy coastal plains: 31 years of sampling efforts of the “Laboratório de Ecologia de Vertebrados, Universidade do Estado do Rio de Janeiro”

“…For example, our data on lizard thermal ecology allowed conducing a global collaborative study aiming to understand the effects of climate change on the thermal niche of lizards around the world and to assess its role on the extinction of populations and species of lizards worldwide (Sinervo et al, 2010). We have also investigated feeding and foraging habits of different components of herpetofauna in restinga which allowed us to understand the trophic relationships among sympatric lizard species, frogs and other local vertebrates and invertebrates as prey and predators to produce an approximation to a trophic net among species in a restinga area in the state of Rio de Janeiro (Rocha and Vrcibradic, 1998), and to assess how adult lizards may constitute a mortality source for juvenile lizards in their own communities (Siqueira and Rocha, 2008 -Rocha, 2008). An important issue is some differences in age at maturity among populations of the same species and a general trend of an effect of female body size on clutch size, egg volume and/or on relative clutch mass (Rocha and Vrcibradic, 1999;Vrcibradic and Rocha, 2011;Winck and Rocha, 2012;Menezes and Rocha, 2014).…”

Reproductive and fat body cycles of Tropidurus hispidus and Tropidurus semitaeniatus (Squamata, Tropiduridae) in a caatinga area of northeastern Brazil

“…Behavioral acts such as movement on sand and quick escape from predators may be affected by a greater clutch size, representing impor tant evolutionary pressures for reduction in clutch size (Shine 1980). In some tropidurid species, clutch size is positively related to female body size (Van Sluys 1993, Cruz 1998, and in many lizard species, larger females tend to produce larger clutches (Tinkle et al 1970, Rocha 2008. Tropidurus hispidus is apparently not an exception, since female SVL explained 65 % of the variation in clutch size.…”

When invasion may not be harmful: niche relations in a lizard assemblage

“…, Fialho et al . , Hemidactylus mabouia : Anjos & Rocha , Gymnodactylus darwinii : Carvalho & Araújo , Ameiva ameiva : Rocha , Cnemidophorus littoralis : Menezes et al . , Tupinambis merianae : Winck et al .…”