Venomous Species (Araneae, Haplogynae, Sicariidae) from Brazil: 2n♂ = 23 and XXY Sex Chromosome System as Shared Characteristics.

The family Sicariidae comprises the genera , and . This latter is subdivided in eight monophyletic groups based on genitalia morphology and molecular analyses: , , , and (South America); (North America); (Mediterranean); and (Africa). In Brazil, the genus is represented by 50 species.

Comparative cytogenetics of seven Ctenidae species (Araneae).

The present study elevates the number of cytogenetically analyzed ctenid species and genera from two to eight and six, respectively, presenting comparisons between chromosomal data obtained and the phylogenetic hypothesis proposed in the literature. Six ctenid species presented 13 autosomal pairs, exhibiting either X1X2O (Ctenus ornatus, Ctenus sp., Parabatinga brevipes and Phoneutria nigriventer) or X1X2X3O sex chromosome systems (Nothroctenus sp.