BLUNTNOSE SPINY DOGFISH
A dogfish that has been re-described since its discovery
The Bluntnose Spiny dogfish (Squalus acutipinnis) is a species of dogfish belonging to the family Squalidae. It was originally described by Regan in 1908, and since has been re-described in 2014 and accepted in 2015 by Viana and De Carvalho, but not reclassified and still remains the current species.
Family: Squalidae – Dogfish Sharks
Common Name– Dogfish Sharks
Common Name– Dogfish Sharks
Status: IUCN Red List DATA DEFICIENT
Average Size and Length: Average known length of the Bluntnose Spiny dogfish is between 1-2.3 feet.
Current Rare Mythical Sightings: Original description: Regan, 1908. Re described 2014 and accepted 2015 by Viana and De Carvalho.
Teeth and Jaw: The Bluntnose Spiny dogfish has unicuspid teeth similar in both jaws. They are labial-lingually flattened and alternate, and are broad at the crown. The teeth are broader in lower jaw than in upper jaw; the cusp is robust and slightly elongated, diagonal and upwardly directed. There is a mesial cutting edge that is concave. The distal heel is markedly rounded; slender mesial heel. The apron is short in the upper teeth and more elongated in lower teeth; lectotype with three series of functional teeth in upper jaw and two series in lower jaw. The tooth row formula is 13/11.
Head: The snout of the Bluntnose Spiny dogfish is rounded and short. The preorbital snout length 6.3% for lectotype, 6.5–7.1% TL, prenarial snout length 0.8 (0.9–1.0) times inner nostril-labial furrow space.
Denticles: The dermal denticles are broad at the crown with the length equal to the width.
Tail: The caudal fin of the Bluntnose Spiny dogfish has a narrow dorsal lobe and continuous caudal fork between lobes.
Demographic, Distribution, Habitat, Environment and Range: The Bluntnose Spiny dogfish can be found in the western Indian Ocean from Kwazulu-Natal to Algoa Bay in the Eastern Cape and Mauritius. There are few records from the Atlantic side of South Africa but without occurrences to the north-northwest of Cape Town.
Aesthetic Identification: The Bluntnose Spiny dogfish is greyish or brownish above and pale below. The first dorsal fin is upright, triangular in shape and low (8.2%, 8.0–9.3% TL). The pectoral fins are broad with the posterior margin conspicuously greater than trunk height when pressed against the body. There are distinguishable L-shaped free rear tips of pectoral fins and the pectoral fins are not lobe-like. The triangular first dorsal fin is elongated as well as the first dorsal spine. The margins of pectoral and caudal fins white but not uniform.
Biology and Reproduction: The vertebra count of the Bluntnose Spiny dogfish is distinguishable from other species. The Bluntnose Spiny Dogfish does have known parasites. The Bluntnose Spiny dogfish is thought to be ovoviviparous.
Behavioral Traits, Sensing and Intelligence: Unknown.
Bluntnose Spiny Dogfish Recorded Attacks on Humans: Not a threat to humans
Sarah T. de F. Viana, Sarah T. de F. Viana, Marcelo R. de Carvalho, Marcelo R. de Carvalho, “Redescription of Squalus acutipinnis Regan, 1908, a Valid Species of Spiny Dogfish from Southern Africa (Chondrichthyes: Squaliformes: Squalidae),” Copeia 104(2), (21 June 2016).
Received: 5 December 2014; Accepted: 1 September 2015; Published: 21 June 2016