|Researched by||Emma Snowden||Refereed by||This information is not refereed.|
|Other common names||-||Synonyms||-|
A short-snouted ray with typical diamond shape and sharply angled pectoral fins approaching 90 degrees. The colour is variable, usually a mottled, blotchy brown to grey, with numerous small dark spots and yellowish patches. In young fish the yellow patches form distinct spots, each outlined with smaller dark spots. The underneath is an off-white with grey to black margins. Dorsally the body is covered with coarse prickles, which are present from hatching. In addition, large, backward pointing thorns (called bucklers) are scattered over the dorsal surface, each of which has a thick button-like base. These thorns are particularly numerous on the tail and in females present in a line along the back. Raja clavata can grow up to 1 m long however 85 cm is the usual maximum length. Females are larger than males.
On account of its abundance, Raja clavata is an important fish commercially. Most of the skate found in fishmongers is likely to be thornback ray also known as the 'roker'. Thornback rays lay up to 150 egg cases a year. The empty egg cases are a common sight washed up on the shore and are known as mermaids purses. Thornback rays tend to lie covered in sand during the day and feed at night on a range of bottom-dwelling animals. They will eat fish such as sand eels, herrings, sprats and small flatfish however shore and swimming crabs and brown shrimps are its main food. Raja clavata resembles other rays found in area, but is distinguished by the large 'buckler' thorns scattered on dorsal surface.
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Last Updated: 08/05/2008