Food resource utilization of the skates Rioraja agassizii (Müller & Henle, 1841) and Psammobatis extenta (Garman, 1913) on the continental shelf off Ubatuba, South-eastern Brazil.

Biological parameters and population structure of Psammobatis extenta in Ubatuba region, north coast of the State of So Paulo, Brazil

Specimens of the zipper sand skate Psammobatis extenta were collected in the region of Ubatuba o¡ the northern coast of the State of Sa‹ o Paulo, Brazil, monthly for one year (January^December 2000), at 25to 40-m isobaths. A total of 123 individuals were caught. The total length (TL) of females averaged 224.6mm, and of males 217mm. The overall sex ratio was 1:1. Analysis of the length^weight re...

EGG CAPSULES OF THE LITTLE SKATE, Psammobatis extenta (GARMAN, 1913) (CHONDRICHTHYES, RAJIDAE)

Analysis of food habits of skate Rioraja agassizii (Elasmobranchii, Rajidae) from southern Brazil.

Catches and exports of skate Rioraja agassizii place this species as "vulnerable to extinction" on the IUCN Red List; therefore, biological and ecological knowledge becomes an important instrument for its conservation control. This study described and quantified the diet composition of R. agassizii by means of stomach analysis contents in the periods 2005-2006 and 2012-2013. We analyzed and qua...

Ultrastructural and phylogenetic data of Chloromyxum riorajum sp. nov. (Myxozoa), a parasite of the stingray Rioraja agassizii in Southern Brazil.

We describe a new myxozoan parasite found infecting the gall bladder of the cartilaginous fish Rioraja agassizii (Rajidae) from the South Atlantic coast of Brazil. Light microscopy, scanning and transmission electron microscopy and phylogenetic data were used. Numerous irregular polyspqric plasmodia externally covered by numerous microvilli containing different stages of sporogony, including fr...

Biogeographic patterns in the cartilaginous fauna (Pisces: Elasmobranchii and Holocephali) in the southeast Pacific Ocean

The abundance and species richness of the cartilaginous fish community of the continental shelf and slope off central Chile is described, based on fishery-independent trawl tows made in 2006 and 2007. A total of 194,705 specimens comprising 20 species (9 sharks, 10 skates, 1 chimaera) were caught at depths of 100-500 m along a 1,000 km transect between 29.5°S and 39°S. Sample site locations wer...