Molecular evidence supporting the expansion of the geographical distribution of the Brazilian cownose ray (Myliobatiformes: Rhinopteridae) in the western Atlantic.

The genus Rhinoptera is composed of eight species widely distributed in tropical, subtropical and temperate coastal waters, which inhabit bays, estuaries and river mouths. Cownose ray Rhinoptera bonasus has been reported to inhabit the Western Atlantic including the Gulf of Mexico and the Caribbean, whereas the Brazilian cownose ray R. brasiliensis has been considered endemic to the coast of Brazil.

Spatial and temporal genetic homogeneity of the Monterey Spanish mackerel, , in the Gulf of California.

The genetic homogeneity of the Monterey Spanish mackerel population in the Gulf of California was confirmed using nine nuclear microsatellite loci in combination with mitochondrial cytochrome b gene sequences. Samples were collected from the upper and central Gulf areas, representing the two main biogeographical regions of the Gulf. The analyses support the existence of a single panmictic population of inhabiting the Gulf of California which in terms of fishery management represents a single genetic stock.

Complete mitochondrial genome of the porbeagle shark, (Chondrichthyes, Lamnidae).

We report for the first time, the complete mitochondrial genome sequence of the porbeagle shark, , from a specimen collected from offshore waters of New England, USA in the western North Atlantic Ocean. The genome structure of this species is similar to the other reported shark mitogenomes. The genome sequence has a total length of 16,697 bases; similar in size to the mtDNA genomes reported for other lamnid species.

Complete mitochondrial DNA genome of bonnethead shark, Sphyrna tiburo, and phylogenetic relationships among main superorders of modern elasmobranchs.

Elasmobranchs are one of the most diverse groups in the marine realm represented by 18 orders, 55 families and about 1200 species reported, but also one of the most vulnerable to exploitation and to climate change. Phylogenetic relationships among main orders have been controversial since the emergence of the Hypnosqualean hypothesis by Shirai (1992) that considered batoids as a sister group of sharks. The use of the complete mitochondrial DNA (mtDNA) may shed light to further validate this hypothesis by increasing the number of informative characters.