Meeting Abstract
Tetraodontiform fishes represent one of the most peculiar radiations of teleost fishes. In spite of this, we do not currently have a consensus on the phylogenetic relationships among the major tetraodontiform lineages, with different morphological and molecular datasets all supporting contrasting relationships. We present the results of the analysis of tetraodontiform interrelationships based on a large matrix consisting of full mitogenomes, 20 nuclear loci (~ 30.000 combined nucleotides) and 250 morphological characters for 90 taxa, including representatives of all of the 19 currently recognized extant and fossil families. Bayesian and maximum likelihood analyses strongly support novel relationships among the major tetraodontiform lineages. The new analysis also suggests a key role of fossils in helping us understand how highly derived morphological structures found in extant clades may have originated. A second dataset, consisting of nine nuclear and mitochondrial loci sequenced for 255 species (~55% extant species) is then used for a time calibrated analysis that reveals a late Cretaceous stem origin for most families. This was followed by an Eocene-Oligocene radiation that was likely facilitated by the establishment of large scleractinian reef habitats across tropical and subtropical oceans.
