Dactylobatus clarkii

Dactylobatus clarkii
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Rajiformes
Family: Rajidae
Genus: Dactylobatus
Species: D. clarkii
Binomial name
Dactylobatus clarkii
(Bigelow & Schroeder, 1958)
Synonyms

Raja Clarki Bigelow & Schroeder, 1958[2]
Raja Clarkii Bigelow & Schroeder, 1958[2]

Dactylobatus clarkii, Clark's fingerskate or the hookskate, "is a medium-sized (to 75 cm TL) but poorly known, deepwater skate."[1] The distribution of the hookskate is considered patchy and covers the western central and southwest Atlantic, including the east coast of Florida (USA), throughout the Gulf of Mexico (Guatemala, Lesser Antilles, Colombia, Venezuela and Suriname), and off Rio Grande do Sul (southern Brazil).[1]

Description

A 1967 survey of specimens included 14 males ranging from 228–668 mm (8.98–26.3 in), and eight females from 176–747 mm (6.93–29.4 in).[3] It has been found on muddy bottoms of the continental slope at depths of 315–915 metres (1,030–3,000 ft).[1]

Bigelow and Schroeder describe the species as "characterized among western Atlantic rajids by the presence of a band of formidable and very sharp thorns extending along the margin of the lower surface from the tip of the snout almost to the outer corners of the disc."[3] The number of thorns in the median row varied from 30 to 43, without apparent relation to the size or age of the skate, while a triangular patch of thorns in the nuchal–scapular area ranged from one to five.[3]

The upper surface is brown, with darker punctulations scattered across the disc, pelvics, and tail, and some specimens have "conspicuous white spots," which if present are located in the same parts of the disc.[3]

"Eggs have horn-like projections on the shell."[4]

Diet

"Stomach contents include one specimen of Mullus argentinae [Argentine goatfish], remains of a teleost fish and predominance of Myctophidae fishes."[4]

Conservation Status

The IUCN assessed the species' status as Data Deficient, "due to the limited knowledge of its biology and extent of capture in fisheries ..."[1]

Media Attention

A misidentified 427 cm (14 ft) hookskate was widely reported to be caught and released on November 23, 2013 near Miami Beach,[5][6] but was later identified by George H. Burgess of the Florida Museum of Natural History as a roughtail stingray (Dasyatis centroura).[6]

References

  1. 1 2 3 4 5 J. M. Brash & J. D. McEachran (2009). "Dactylobatus clarkii". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved November 26, 2013.
  2. 1 2 "Itis Standard Report Page: Dactylobatus clarkii". Integrated Taxonomic Information System. Retrieved 13 December 2013.
  3. 1 2 3 4 Bigelow, Henry B.; Schroeder, William C. (5 April 1968). "Additional Notes on Batoid Fishes from the Western Atlantic". Breviora (Cambridge: Museum of Comparative Zoology, Harvard University) (281): 8–9. ISSN 0006-9698. Retrieved 13 December 2013.
  4. 1 2 "Dactylobatus clarkii, Hookskate". Fishbase. Retrieved 13 December 2013.
  5. "They're gonna need a bigger boat: Rarely-seen 14-foot, 800lb deep-sea 'dinosaur' skate caught off Florida coast". Daily Mail. 26 November 2013. Retrieved 13 December 2013.
  6. 1 2 Thomas, Pete (25 November 2013). "Enormous rare sea creature hauled from depths by Florida shark fisherman". GrindTV. Retrieved 13 December 2013.
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