Echinorhinus brucus (Bonnaterre, 1788) in the Caribbean Sea: A recurrent visitor, or are the artisanal fisheries exploiting deeper waters?

Documentation of Echinorhinus brucus, (Bonnaterre, 1788) in the western Atlantic primarily relies on chance observations. Georeferenced records in this area remain notably scarce. This study contributes the second Venezuelan and seventh Caribbean Sea specimens, increasing the western Atlantic count to 15 individuals. All specimens gathered here were sexually mature, with a slight dominance of females. Our bramble shark record appears to be driven more by the interplay of its biology and environmental factors than being a deliberate deep-sea fishery activity, which likely occurs in the Southern Caribbean area.

Biological notes on the reef stingray, Urobatis concentricus, an endemic species of Mexico.

This study found that the reef stingray Urobatis concentricus presents a matrotrophic aplacental viviparous reproduction with yolk sac and trophonemata formation. Growth of ovarian follicles occurs asynchronously and continuously with fecundity of three embryos per female. A maximum size of 58·4 cm total length and 37·6 cm disc width was recorded, corresponding to a mature female of 3 or 4 years of age.

Lesser devil rays Mobula cf. hypostoma from Venezuela are almost twice their previously reported maximum size and may be a new sub-species.

Three rays opportunistically obtained near Margarita Island, Venezuela, were identified as lesser devil rays Mobula cf. hypostoma, but their disc widths were between 207 and 230 cm, which is almost double the reported maximum disc width of 120 cm for this species. These morphometric data suggest that lesser devil rays are either larger than previously recognized or that these specimens belong to an unknown sub-species of Mobula in the Caribbean Sea. Better data are needed to describe the distribution, phenotypic variation and population structure of this poorly known species.

Cryptic Caribbean species of Scorpaena (Actinopterygii: Scorpaeniformes) suggested by cytogenetic and molecular data.

Cytogenetic and molecular analyses enabled identification of two cytotypes among individuals of the spotted scorpion fish Scorpaena plumieri from Margarita Island, Venezuela. Cytotype 1 was characterized by 48 subtelo-acrocentric chromosomes and fundamental number (number of chromosome arms; FN) equalled 48, while cytotype 2 was characterized by two metacentric and 46 subtelo-acrocentric chromosomes and FN was 50. These cytotypes also differed in the location of the ribosomal gene clusters and in the distribution of the constitutive heterochromatin. Moreover, fish from the cytotypes 1 and 2 were found to belong to distinct mitochondrial lineages. The presence of two S. plumieri cytotypes from two lineages separated by high genetic distance suggests that they correspond to sympatric cryptic species.