Family RAJIDAE


Common name: Skates

Silhouette

Summary:

Small to large rays with almost circular to rhomboidal discs. Skates are mostly marine fishes, occurring from shore to depths of more than 2000 m.

The distinguishing features of the genera and species are often based on internal cartilage structures, therefore external characters not always reliable for identifying taxa.


Cite this page as:
Peter R. Last & Will White, Skates, RAJIDAE in Fishes of Australia, accessed 23 Jun 2018, http://fishesofaustralia.net.au/Home/family/200

More Info


Family Taxonomy

The family comprises more than 20 currently recognised genera and at least 278 species worldwide. It is represented in Australia by 9 genera. More information on Australian family members in Last & Stevens (2009).

Family Description

The family is characterised by a combination of the following characters: snout variable in shape, mostly supported by central cartilage, 5 gill slits, unique patterns of thorns and granulations on dorsal surface, rather slender tail usually with 2 (rarely 1 or none) small dorsal fins near apex, no stinging barbs on tail, ventral fins generally deeply incised with anterior and posterior lobes varying in relative length between species, caudal fin small or indistinguishable and no anal fin.

Skates exhibit marked sexual dimorphism with adult males generally having distinctive patches of hooks and thorns on the central and anterior parts of the pectoral fins, known as alar and malar regions respectively, and a more curvaceous disc than females.

Family Reproduction

Skates are egg layers (oviparous) with females producing individual eggs enclosed in flattened rectangular chitinous egg cases, commonly referred to as mermaid's purses.

Author

Peter R. Last & Will White