Preliminary karyotypic data on the Nile pufferfish Tetraodon lineatus (Tetraodontidae)

The family Tetraodontidae comprises 193 valid species of teleost fish distributed in tropical and subtropical regions worldwide. Available cytogenetic information for 31 species indicates extensive variability in diploid chromosome number (2n) ranging from 28 to 46. Here, we present the preliminary cytogenetic characteristics of Tetraodon lineatus Linnaeus, 1758, the type species of Tetraodon Linnaeus, 1758, which is the type genus of the family. The karyotype of a single male of T. lineatus from the White Nile Basin in Ethiopia comprised 12 metacentric/submetacentric and 28 subtelocentric/acrocentric chromosomes (2n = 40, FN = 52). These data are briefly compared with the available cytogenetic information on other tetraodontid genera, summarized according to the current taxonomic classification.