Angular angelshark or Squantina guggenheim is a species of shark in the Squantinidae family. They are found in Brazil, Uruguay, and Argentina living in marine, brackish, and demersal environments at depths of 4-360 m. Their typical food sources consist of bony fish, crustaceans, and mollusks.[1]
Morphology
Squantina guggenheim is shaped like a ray and in males, a spiny surface is located on its pectoral fins.[1] However, this spiny surface is absent in females and younglings. This spiny structure is thought to help males hold females while mating. Both males and females range from 89-130 cm in length. S. guggenheim have 18-22 teeth in the upper and lower jaw.
Life Cycle
Squantina guggenheim like some Chondrichthyes is ovoviviparous. The right ovary has been found to have few oocytes and is non-functional.[2] Pregnancy lasts for 9-12 months and litters typically consist of 3-9 pups. Birth is given in shallow waters.[3]
Distribution
Squantina guggenheim is found in the Southwestern Atlantic. They are abundant along the coast of Argentina, Uruguay and Brazil. This area is a subtropical zone and is at a latitude of 20°S - 45°S and a longitude of 68°W - 40°W.[1] Typically, S. guggenheim are found in sandy or muddy areas of the ocean floor.[3]
Conservation
S. guggenheim is considered an endangered species by the IUCN red list due to overfishing and are more susceptible due to the fact they are bottom dwellers. In addition, it may be possible females leave their young earlier on due to the stresses induced from fishing. Currently, Brazil has not taken any action in helping restore this species population.[3]
References
|
|---|
|
|
|---|
Hemigaleidae (Weasel sharks) | | Hemipristis | |
|---|
| Chaenogaleus |
- Hooktooth shark (C. macrostoma)
|
|---|
| Hemigaleus | |
|---|
| Paragaleus |
- Whitetip weasel shark (P. leucolomatus)
- Atlantic weasel shark (P. pectoralis)
- Slender weasel shark (P. randalli)
- Straight-tooth weasel shark (P. tengi)
|
|---|
|
|---|
| Leptochariidae | |
|---|
Proscylliidae (Finback sharks) | | Ctenacis |
- Harlequin catshark (C. fehlmanni)
|
|---|
| Eridacnis | |
|---|
| Proscyllium |
- Graceful catshark (P. habereri)
- P. venustum
|
|---|
|
|---|
| Pseudotriakidae | |
|---|
Sphyrnidae (Hammerhead sharks) | |
|---|
Triakidae (Houndsharks) | | Furgaleus | |
|---|
| Galeorhinus | |
|---|
| Gogolia |
- Sailback houndshark (G. filewoodi)
|
|---|
| Hemitriakis |
- Deepwater sicklefin hound shark (H. abdita)
- Sicklefin hound shark (H. falcata)
- Japanese topeshark (H. japanica)
- Whitefin topeshark (H. leucoperiptera)
- Ocellate topeshark (Hemitriakis Sp.A)
|
|---|
| Hypogaleus |
- Blacktip tope (H. hyugaensis)
|
|---|
| Iago |
- Longnose houndshark (I. garricki)
- Bigeye houndshark (I. omanensis)
- Lowfin houndshark (Iago Sp.A)
|
|---|
Mustelus (Smooth-hounds) | |
|---|
| Scylliogaleus |
- Flapnose houndshark (S. quecketti)
|
|---|
| Triakis | |
|---|
|
|---|
| Carcharhinidae |
- Large family listed below
|
|---|
| Scyliorhinidae |
- Large family listed below
|
|---|
|
|
|
Family Scyliorhinidae (Catsharks) |
|---|
| Apristurus | |
|---|
| Asymbolus |
- Australian spotted catshark (A. analis)
- A. funebris
- Western spotted catshark (A. occiduus)
- Pale spotted catshark (A. pallidus)
- A. parvus
- A. rubiginosus
- Variegated catshark (A. submaculatus)
- Gulf catshark (A. vincenti)
|
|---|
| Atelomycterus | |
|---|
| Aulohalaelurus |
- New Caledonia catshark (A. kanakorum)
- Australian blackspotted catshark (A. labiosus)
|
|---|
| Cephaloscyllium | |
|---|
| Cephalurus | |
|---|
| Figaro | |
|---|
| Galeus | |
|---|
| Halaelurus | |
|---|
| Haploblepharus | |
|---|
| Holohalaelurus | |
|---|
| Parmaturus |
- White-tip catshark (P. albimarginatus)
- White-clasper catshark (P. albipenis)
- Beige catshark (P. bigus)
- Campeche catshark (P. campechiensis)
- Velvet catshark (P. lanatus)
- McMillan's catshark (P. macmillani)
- Blackgill catshark (P. melanobranchus)
- Salamander shark (P. pilosus)
- Filetail catshark (P. xaniurus)
- Shorttail catshark (Parmaturus sp. A)
|
|---|
| Pentanchus |
- Onefin catshark (P. profundicolus)
|
|---|
| Poroderma | |
|---|
| Schroederichthys | |
|---|
| Scyliorhinus | |
|---|
|
|
|
|
|
|
|
|
|
|---|
Centrophoridae (Gulper sharks) | |
|---|
| Dalatiidae | |
|---|
| Etmopteridae | |
|---|
Oxynotidae (Rough sharks) | |
|---|
Somniosidae (Sleeper sharks) | | Centroscymnus | |
|---|
| Centroselachus | |
|---|
| Proscymnodon |
- Largespine velvet dogfish (P. macracanthus)
- Plunket shark (P. plunketi)
|
|---|
| Scymnodalatias | |
|---|
| Scymnodon | |
|---|
| Somniosus | |
|---|
| Zameus | |
|---|
|
|---|
Squalidae (Dogfish sharks) | | Cirrhigaleus |
- Roughskin spurdog (C. asper)
- Mandarin dogfish (C. barbifer)
|
|---|
Squalus (Spurdogs) | |
|---|
|
|---|
|
|
|
Taxon identifiers |
|---|
| Squatina guggenheim | |
|---|