The fish was hauled up in its nets near Whalfirth at the north end of Yell Sound on Tuesday 5th October and donated to the NAFC Marine Centre in Scalloway.
However staff were amazed to discover that it was a violet stingray (Pteroplatytrygonviolacea) rather than a common stingray, itself quite rare around the isles.
According to Dr Chevonne Laurenson of the centre there are only nine previously published records of a violet stingray in the north-eastern Atlantic, two of which were in the North Sea and the furthest north of those was approximately 57°N 5°E, meaning the Guardian Angell find is a new northern record.
The identifying features of the violet stingray are plain dark colouration on both the upper and lower surfaces, a membranous fold of skin on the underside of the tail beneath the spine and a short snout which only protrudes slightly from the front margin of the animal.
Violet stingrays are common and widespread in tropical and warm temperate oceanic waters, including the Indian, Pacific and Atlantic Oceans. The species has been recorded from the surface to 380m depth and can either live on the bottom or in the water column. It feeds on jellyfish, squid, fish and small crustaceans. Females of this species incubate eggs internally and give birth to live young rather than laying “mermaids purses” as is the case in many other skates and rays.
The stingray caught was a female, 55cm across the wings. The body was 47cm and the total length was 112cm although the end of the tail was missing.
Dr Laurenson said: “We are delighted to have been able to identify such a rare fish and are grateful to the Guardian Angell crew for donating their find. We are always keen to hear of unusual catches so that information and photos can be added to the new Discovery Zone section of our website.”