Cytogenetic studies in six species of tropiduridae (Sauria)

Cytogenetic studies were performed on six tropidurid lizards: Tropidurus mucujensis, T hispidus, T montanus, T semitaeniatus, T spinulosus and Uranoscodon superciliosus. Conventional and differential (C- and R-bands and Ag-NORs) staining techniques were employed for the characterization of the karyotypes. The analyses were carried out in order to establish the morphological characterization of macro and microchromosomes, the R- and C-banding patterns as well as the silver staining of nucleolus organizer regions (Ag-NORs). R-banding was obtained after in vitro incorporation of 5-bromodeoxyuridine (BrdU). For some species, the banding patterns are described for the first time. All species presented a diploid number of 2n=36, with a basic karyotype constituted by 12 metacentric or submetacentric macrochromosomes and 24 microchromosomes (12M+24m). Although these species present a conservative karyotype, most of them are distinguished by the morphology of the macro and microchromosomes, by location of Ag-NORs, and by amount and distribution of constitutive hetcrochromatin. Sex determination of the XX:XY type was found in T hispidus, T montanusand U. superciliosus. The presence of species specific karyotypes in T spinulosus and U. superciliosus is suggested.

Notes on the ecology and karyotypic description of Strobilurus torquatus (Sauria, Iguanidae)

Uma populaçäo relativamente densa de Strobilurus torquatus foi encontrada em Säo José, próximo à Itabuna, Estado da Bahia, na Mata Atlântica do Brasil. Este lagarto, aparentemente raro, é um heliófilo de floresta e se alimenta de formigas que obtem em vários níveis nos troncos das grandes árvores e ocasionalmente, no chäo. O dimorfismo sexual é aparente no comprimento rostro-anal e da tíbia: os machos possuem tíbias mais longas e grossas do que as fêmeas. As fêmeas grávidas têm ninhadas de 2 a 3 ovos. Os estudos citogenéticos mostraram 2n = 36 cromossomos, caracterizados por 12 macrocromossomos e 24 microcromossomos e um mecanismo de determinaçäo do sexo XX:XY. Também säo apresentados por padröes de bandas C, localizaçäo das regiöes organizadoras de nucléolo, bandas R após tratamento in vivo com 5-bromodeoxiuridina (5-BrdU) e dados meióticos de machos