Rhinidae

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Rhinidae
Round-headed fiddle-ray (Rhina ancylostoma)

Round-headed fiddle-ray ( Rhina ancylostoma )

Systematics
Class : Cartilaginous fish (Chondrichthyes)
Subclass : Euselachii
Subclass : Plate gill (Elasmobranchii)
without rank: Stingray (batoidea)
Order : Rhinopristiformes
Family : Rhinidae
Scientific name
Rhinidae
JP Müller & Henle , 1841

The Rhinidae are a family of the rays (Batoidea). The family includes three genera with a total of nine species from the group of so-called violin or guitar rays. Two of these genera are morphologically quite different and have been assigned to different families in the past. The sister group relationship of the two genera is based primarily on molecular biological studies. The third genus was only introduced in mid-2016.

features

In the rays of the Rhinidae, the trunk and pectoral fins are clearly separated as in the saw rays , and not grown together to form a body disc , as in the typical rays or the stingray-like . The pectoral fins are triangular and only begin behind the eyes. The first dorsal fin lies well in front of the caudal peduncle above the pelvic fins. The tail is slightly longer than the head and torso and has a fold of skin on each side, which forms a keel that extends to the well-developed caudal fin. The caudal fin has a clearly developed lower lobe. The head is pointed ( Rhynchobatus ) or rounded at the front ( Rhina ). The nostrils are long and narrow and are slightly sloping. The spray hole is large and in Rhynchobatus has two folds of skin on the rear edge; with Rhina it is without a fold. The mouth is covered with strong round or oval teeth that do not have any distinct humps. The skin of the fish is covered with small placoid scales . Thorns are developed differently and can be found along the center line of the back, above the eyes, in two or three short rows on the "shoulders" and sometimes on the muzzle. In the genus Rhina , the very strong thorns stand on raised skin ridges.

The largest species, Rhynchobatus djiddensis, can reach a length of over three meters and a weight of over 200 kg. Usually the rays are yellowish to gray-brown in color on their upper side, often with white spots or eye spots and black spots on the base of the pectoral fin. The ventral side is whitish, sometimes with black spots on the muzzle.

Genera and species

Rhynchobatus australiae

literature

  • Last, PR, Séret, B. & Naylor, GJP (2016): A new species of guitarfish, Rhinobatos borneensis sp. nov. with a redefinition of the family-level classification in the order Rhinopristiformes (Chondrichthyes: Batoidea). Zootaxa , Vol 4117, No 4: 451-475. DOI: 10.11646 / zootaxa.4117.4.1

Individual evidence

  1. ↑ a b Séret, B. & Naylor, GJP (2016): Rhynchorhina mauritaniensis , a new genus and species of wedgefish from the eastern central Atlantic (Elasmobranchii: Batoidea: Rhinidae). Zootaxa , 4138 (2): 291-308. doi: 10.11646 / zootaxa.4138.2.4

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