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DAILY NEWS ANALYSIS

  • 11 January, 2024

  • 3 Min Read

Elasmobranch Species

Shark & ray meat (elasmobranch meat) consumption no longer restricted to India’s tribal & coastal peoples.

  • Elasmobranch is a subclass of the Class Chondrichthyes: Cartilaginous Fishes, which consists of sharks, rays, skates, and chimaeras.

The rise in demand for elasmobranch meat could lead to more unsustainable fishing of shark species.

Difference - The other subclass of cartilaginous fish, the Holocephali, consists of Chimaeras, ratfish (Genus Chimaera) and elephantfish (Genus Callorhynchus).

  • The main differences between these two subclasses are the structure of their gills and how they grow in the embryo.
  • Holocephali has four-gill slits with a gill cover (an operculum); while Elasmobranchs have five to seven, external gill slits with no gill cover.
  • The term Elasmobranch actually means naked gill.
  • In addition, in the Holocephali the upper jaw is fused to the skull, unlike in the Elasmobranchii.

Features - A skeleton made of cartilage; No swim bladders; Five to seven pairs of gills opening individually to the exterior; Rigid dorsal fins; Rough skin made up of small dermal denticles.

  • Elasmobranch skin is made of tiny, hard, tooth-like placoid scales called denticles.
  • Elasmobranchs are renowned for their highly tuned senses, which make them incredibly successful in their environment.
  • Many Elasmobranchs can sense electrical impulses of other animals but not generate their own special fields, as they possess sensory organs called the Ampullae of Lorenzini.
  • Females have no obvious external reproductive structures, whilst males have two extensions of the pelvic fin known as claspers.

India has banned the live finning of sharks and the export of fins of all shark and ray species and ten species are completely protected from any fishing and trade.

Source: downtoearth


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