Amblyraja radiata Donovan 1808

• Main Authors: Gordon, Cat A., Hood, Ali R., Ellis, Jim R.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2016
• Subjects: Biodiversity; Taxonomy; Animalia; Chordata; Elasmobranchii; Rajiformes; Rajidae; Amblyraja; Amblyraja radiata; Barents Sea; Iceland; Northeast Atlantic
• Online Access: https://doi.org/10.5281/zenodo.5631354; http://treatment.plazi.org/id/03C2E354FFCDFFCFFF49F9FBFF215F39

Amblyraja radiata (Donovan, 1808) Distribution. Starry skate ( A. radiata ) is a boreo-Arctic species that, in the Northeast Atlantic, is common from the central North Sea to Iceland and the Barents Sea (Stehmann & Bürkel, 1984). Verified records submitted to the Great Eggcase Hunt were usually collected along North Sea coasts, from north Norfolk up to the Shetland Islands. However, one unusually large specimen (Figure 2 a) was reported in January 2015 from Borth, Cardigan Bay (Wales), which is outside the expected geographic range (see below). Material examined. Ninety-four eggcases were examined in total (excluding the unusual specimen collected from Borth). Specimens were obtained primarily from North Sea trawl surveys (n = 79) with additional specimens available from beach collections (n = 10) and museum specimens (n = 5) historically collected from Scarborough (North Sea coast, BMNH 1928.2.8.2.1–4, BMNH 1928.1.11.1). Specimens from the North Sea were captured at a range of trawl locations over the area from 55.6– 61.3°N and 0.5°W to 5.8°E, ranging from 37–170 m water depth. Description. The eggcase of A. radiata (Figure 2 b) is generally small. Excluding the large aberrant specimen from Borth, the mean total eggcase length is 101.2 ± 10.6 mm (range = 72.2–129.0), and eggcase length is 34.2 ± 1.1 mm (range = 32.7–36.7 mm) without horns. Eggcase width is 32.8 ± 2.6 mm (25.6–36.7 mm). The length and width of eggcases from historical museum specimens (n = 5) were within the size ranges recorded in contemporary samples. The dorsal surface is strongly convex and, when newly laid, covered in a thin fibrous layer. The ventral surface is slightly convex in shape but much flatter in comparison to the dorsal surface. Both capsule surfaces have longitudinal striations and latitudinal ridges that give a distinctive texture and pattern (Figure 3 a), ranging from a delicate lattice appearance to a fine rippled effect. Lateral keels (which are often damaged or lost in older specimens) run the length of the capsule from ...