Spiny angel shark (Squatina guggenheim)

Description

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Spiny angel shark fact file

• Description
• Biology
• Range
• Habitat
• Status
• Threats
• Conservation
• Find out more
• Glossary
• References
• Print factsheet

Spiny angel shark description

The spiny angel shark (Squatina Guggenheim) is a small, bottom-dwelling shark, named after the characteristic spines found on the upper surface of the males’ pectoral fins. These spines are used to hold the males position with a female during mating ^{(1) (2)}. 

With a flat, speckled, sandy-coloured body, the spiny angel shark is able to effectively camouflage itself against the ocean floor ⁽¹⁾.

Female and juvenile spiny angel sharks lack the spines found on the pectoral fins of the male ⁽²⁾.

Also known as

Hidden angelshark.

Size

Average total length: 70 - 80 cm ⁽²⁾

Spiny angel shark biology

The spiny angel shark preys on crustaceans, fish and other small sharks ⁽³⁾. This species is nocturnal and will bury into the sea bed to avoid detection, leaving its eyes visible to ambush prey ^{(1) (4)}.

The spiny angel shark has a three year reproductive cycle. The female can give birth at any time of the year, and, after a 10 to 12 month gestation period, will migrate away from deeper seas to give birth in shallow, inshore nursery grounds. The litter size of the spiny angel shark is usually between three and nine pups ^{(1) (2)}.

Spiny angel shark range

The spiny angel shark is found in the southwest Atlantic Ocean, off the coast of Northern Brazil, Uruguay and southern Argentina ⁽¹⁾.

Spiny angel shark habitat

Found mainly on the ocean bed, the spiny angel shark is typically found up to depths of 150 metres ⁽²⁾. This species prefers coastal subtidal sandy or muddy waters ⁽¹⁾.

Spiny angel shark status

The spiny angel shark is classified as Endangered (EN) on the IUCN Red List ⁽¹⁾.

Spiny angel shark threats

One of the greatest threats to the spiny angel shark is from overfishing off the South American coast. As the spiny angel shark is a bottom dweller, it is especially prone to being caught by gillnets and bottom trawling ⁽¹⁾.

As there is very little movement between different populations, the spiny angel shark is prone to local extinction. Intensive fishing occurs in the shallow nursery grounds, and pregnant female spiny angel sharks may to abort embryos when caught, further contributing to the population decline ⁽¹⁾.

The Brazilian population of spiny angel sharks decreased by 85 percent between 2002 and 1984, as a result of overfishing using gillnet methods ⁽¹⁾.

Spiny angel shark conservation

Brazil currently has no measures in place to control the angel shark fishery, although trawling inshore waters is prohibited. Argentina has established a Maximum Permitted Catch of the spiny angel shark, to limit the number of spiny angel sharks caught by fisheries ⁽¹⁾.

Further conservation measures are needed, such as restricting fishing in the shallow water nursery grounds in southern Brazil. As the spiny angel shark is important to many coastal fisheries in Brazil, any conservation measures introduced to protect this endangered fish must also consider the impact to the local economy ⁽³⁾.

Find out more

Find out more about shark species and their conservation: 

• Save Our Seas Foundation:
  http://www.saveourseas.com/
• The Shark Trust:
  http://www.sharktrust.org/

Authentication

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

This species information was authored as part of the ARKive and Universities Scheme.

Glossary

Crustaceans

Diverse group of animals with jointed limbs and a hard external skeleton, characterised by the possession of two pairs of antennae, one pair of mandibles (mouthparts used for handling and processing food) and two pairs of maxillae (appendages used in eating, which are located behind the mandibles). Includes crabs, lobsters, shrimps, woodlice and barnacles.

Gestation

The state of being pregnant; the period from conception to birth.

Nocturnal

Active at night.

Pectoral Fin

The fins on either side of the body just behind the head and the gills that are involved in movement and direction.

References

1. IUCN Red List (October, 2011)
   http://www.iucnredlist.org/
2. Colonello, J., Lucifora, L. and Massa, A. (2006) Reproduction of the angular angel shark (Squatina guggenheim): Geographic differences, reproductive cycle, and sexual dimorphism. ICES Journal of Marine Sciences, 64: 131-140.
3. Vögler, R., Milessi, A. and Quinones, R. (2008) Tropic ecology of Squatina guggenheim on the continental shelf off Uruguay and northern Argentina. The Journal of Fish Biology, 62: 1254-1267.
4. Vögler, R., Milessi, A. and Duarte, L. (2009) Changes in trophic level of Squatina guggenheim with increasing body length: relationships with type, size and trophic level of its prey. Environmental Biology of Fishes, 84: 41-52.