Blackchin Guitarfish Glaucostegus cemiculus

Identity card

Blackchin Guitarfish

Scientific name:
Glaucostegus cemiculus
Year of description:
Geoffroy Saint-Hilaire, 1817
IUCN Status:
Critically Endangered

Appendix II


East Atlantic, from Portugal to Angola and on to the Mediterranean Sea.


At a depth of between 9 and 100 metres.


On average 1.50 m, but can reach 2 m.


Fish and benthic invertebrates.

Conservation program:

Nausicaa coordinates the European conservation programme for the blackchin guitarfish.

Blackchin Guitarfish Glaucostegus cemiculus

The Blackchin guitarfish burrow into the sea floor with great ease and can embed themselves.


Blackchin guitarfish use their tails to swim and advance like sharks, while other rays use their pectoral fins and 'glide' through the water.

They feed on fish and benthic invertebrates.



Did you know?

Where is the animal to be found?

It is found on sandy or muddy seabeds, at depths ranging from 9 to 100 metres. It burrows into the seabed with great ease. Its beige, grainy skin makes it easy to blend in with the sand.

How can it be recognised?

  • The blackchin guitarfish looks like a cross between a ray for the front part of its body and a shark for the rear part.
  • The Glaucostegus family is characterised by a very slender body and dorsal fins behind the pelvises. The tail is asymmetrical and does not have a lower lobe. It measures on average 1.50 m, but can reach 2 m.
  • With its long body and shark-like undulating motion, the blackchin guitarfish Rhinobatus cemiculus differs from its fellow thornback skates in the touch tank or the oceanic manta ray in the High Seas Pool, which use their pectoral fins.

What is distinctive about it?

The blackchin guitarfish is ovoviviparous. It has one to two litters per year, each comprising 4 to 6 embryos.

Threat and protective measure

  • The blackchin guitarfish in critically endangered and continuing to decline.
  • Its trade is regulated by CITES and is even suspended in several countries.
  • In the Banc d'Arguin National Park, it can only be caught by traditional indigenous fishermen.
  • Threatened by overfishing and the deterioration of their habitat, the blackchin guitarfish is listed on the IUCN Red List. Furthermore, blackchin guitarfish do not reproduce particularly abundantly, which adds to the threat to this species.

Other rays that can be discovered in the High Seas tank are the oceanic manta ray, Atlantic pygmy devil rays and spotted eagle rays.

Little blackchin guitarfish are regularly born at Nausicaá

  • Aged about ten years, the male and the three female blackchin guitarfish that gave birth to these babies have grown up in Nausicaá and have already reproduced. Since 2009, 50 blackchin guitarfish have been born. In a few months' time, these little blackchin guitarfish will join a partner structure. In fact, these births are part of a European conservation programme that will become an EEP, coordinated by Nausicaá.
  • The births are recorded in a file and the role of the coordinator is to find a home for these young rays in order to encourage the genetic intermingling that is required to maintain a healthy population.
  • Successful breeding and monitoring in the aquarium improves our knowledge of the animals, particularly through ultrasound scans of pregnant females to observe embryonic development. This knowledge on the fertility of these species contributes to their conservation in the wild.
Blackchin Guitarfish Glaucostegus cemiculus

Where can I find it at Nausicaá?

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