Snakes are among the most successful groups of reptiles, numbering about 3,000 extant species. In spite of centuries of comparative anatomical and morphological studies, many aspects of snake systematics remain unsolved. To better understand the evolution and diversity of genomic characteristics in Serpentes, we analyzed online sequence data of mitochondrial and nuclear genes, as well as cytogenetic data and reviewed other genomic characteristics such as toxin genes. After the analysis of the whole-genome and chromosomal organization, we find that: (1) cytogenetic comparisons could provide a useful tool to investigate intergeneric and tribal relationships within the extremely diverse neotropical xenodontine snakes; (2) toxin genes could also help to understand snake evolution if special care is taken to choose the sequences because of the difficulty in avoiding paralogs; (3) snake phylogeny based on mitochondrial genome sequences is largely consistent with the relationship obtained using nuclear genes.

Sympatric populations of the leaf-frogs Phyllomedusa distincta (2n = 26) and P. tetraploidea (4n = 52) were studied in southeastern Brazil. In a region of sympatry, seven of 15 leaf-frogs were triploid hybrids (3n = 39). The advertisement calls of both species are similar, and may not function adequately as a premating isolation mechanism. Triploids apparently exhibit low fertility or sterility, supporting the assertion that diploid and tetraploid populations are valid species. We suggest that P. tetraploidea originated by autopolyploidy of P. distincta, based on the following evidence: (1) the indistinguishable vocalizations of diploid and tetraploid species, and (2) the geographic distribution of species in the Phyllomedusa burmeisteri group.

BRILL) announces that at its Annual General Meeting of shareholders (AGM), held today, all proposals were approved.

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The karyotypes of two brazilian species of coral snakes (Ophidia: Elapidae): Micrurus corallinus and M. ibiboboca are described for the first time. Cytological preparations were obtained through the technique of squashing, followed by conventional Giemsa staining. The diploid number for Micrurus corallinus was 40 chromosomes with a karyotype formulae 40 (4; 16; 20) with a secondary constriction in the second pair of subtelocentric macrochromosomes. Micrurus ibiboboca is described by the formulae 42 (2; 20; 20) with 2n = 42 with a secondary constriction in the first pair of telocentric macrochromosomes. The karyotypes of M. corallinus and M. ibiboboca present aspects similar to M. lemniscatus and M. surinamensis, the only previously analyzed species of this genus in South America. These four species have the same number of microchromosomes (20), the largest number of telocentric or subtelocentric macrochromosomes and the largest diploid numbers (2n) ever found in the genus Micrurus. These characteristics differ from those of the nine known species of Central America.Keywords

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