Narrowhead catshark

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Narrowhead catshark
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Carcharhiniformes
Family: Scyliorhinidae
Genus: Bythaelurus
Species:
B. tenuicephalus
Binomial name
Bythaelurus tenuicephalus

The narrowhead catshark (Bythaelurus tenuicephalus) is a catshark of the family Scyliorhinidae. This species is described based on one adult and one juvenile male specimen from off Tanzania and Mozambique in the western Indian Ocean. The species differs from its congeners by its slender head and snout, which is only slightly bell-shaped in dorsoventral view without distinct lateral indention. It further differs from B. clevai by attaining a smaller maximum size and having a color pattern of fewer and smaller blotches, larger oral papillae, a shorter snout, and broader claspers without knob-like apex and with a smaller envelope and a subtriangular exorhipidion. Compared to B. hispidus , the species has a longer snout, a longer dorsal-caudal space, broader clasper without knob-like apex, and fewer vertebral centra. In contrast to B. lutarius , B. tenuicephalus attains a smaller size and has a blotched coloration, numerous oral papillae, shorter anterior nasal flaps, a longer caudal fin, a shorter pelvic anal space, and shorter and broader claspers. [2]

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<span class="mw-page-title-main">Quagga catshark</span> Species of fish

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<span class="mw-page-title-main">Bristly catshark</span> Species of shark

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<span class="mw-page-title-main">Antilles catshark</span> Species of shark

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<span class="mw-page-title-main">Atlantic sawtail catshark</span> Species of shark

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Bythaelurus is a genus of deep-water catsharks and part of the family Scyliorhinidae. The genus Bythaelurus Compagno 1988 was first described as a subgenus of Halaelurus Gill 1862 based on several morphological characteristics including a soft body with thin skin, a bluntly rounded snout without a pointed, knob-like tip, and eyes not noticeably elevated on the dorsal surface of the head. Members of this genus are generally found in deep water and have more somber body coloration.

The speckled swellshark is a little-known species of catshark, and part of the family Scyliorhinidae, endemic to the waters off northwestern Australia. It occurs on the outer continental shelf and upper continental slope, at a depth of 150–455 m (492–1,493 ft). This species grows to 69 cm (27 in) long and has a stocky body and a short, broad, flattened head. As its common name suggests, its color pattern consists of many dark spots and white-spotted dark saddles and blotches on a light gray background. The juveniles are yellow with dark spots and lines, and a distinctive eyespot-like mark behind each eye. Like other swellsharks, this species can inflate itself as a defensive measure.

The painted swellshark is a little-known species of catshark, belonging to the family Scyliorhinidae, found in eastern Indonesia. This species reaches a maximum known length of 72 cm (28 in), and has a thick body with a short, broad and flattened head. It is dark gray with a variegated pattern of irregular darker and lighter blotches above, and lighter below with gray blotches and speckling on the snout. Like other swellsharks, it can inflate itself as a defensive measure.

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<i>Bythaelurus stewarti</i> Species of shark

Bythaelurus stewarti, the Error Seamount catshark, is a catshark of the family Scyliorhinidae in the order Carchariniformes. It is endemic to Error Seamount, a guyot located in the Arabian Sea in the western Indian Ocean. Its closest relative is the bristly catshark, which it differs from in its larger size, darker and more mottled coloration, and especially its smaller and less densely concentrated denticles.

<i>Bythaelurus bachi</i> Catshark species

Bythaelurus bachi, commonly known as Bach's catshark, is a species of catshark found in southern Madagascar Ridge in the southwestern Indian Ocean. This stout-bodied catshark is thought to inhabit the deep sea at depths of 910–1,365 m (2,986–4,478 ft).

<i>Bythaelurus vivaldii</i> Catshark species

Bythaelurus vivaldii, Vivaldi's catshark, is a species of catshark found in Northwestern Indian Ocean, specifically in Somalia. It presumably lives in the depths of up to 628 m (2,060 ft).

References

  1. Pollom, R.; Ebert, D.A.; Fernando, S.; Kuguru, B.; Samoilys, M.; Weigmann, S. 2019 (2019). "Bythaelurus tenuicephalus". IUCN Red List of Threatened Species . 2019: e.T110903105A141001987. Retrieved 13 November 2021.
  2. Kaschner, C.J., Weigmann, S. & Thiel, R. (2015): Bythaelurus tenuicephalus n. sp., a new deep-water catshark (Carcharhiniformes, Scyliorhinidae) from the western Indian Ocean. Zootaxa, 4013 (1): 120-138.