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Spinarolo naso lungo africano

Squalus bassi

(Vinana, De Carvalho & Ebert, 2017 )

Ordine: Squaliformi  Famiglia: Squalidae  Genere: Squalus

Descrizione

Original diagnose after VIANA, DE CARVALHO & EBERT, 2017 [25697]: Along-snouted spurdog species from southern Africa that is distinguished from other long-snouted species S. montalbani, S. edmundsi, S. chloroculus, S. nasutus and S. grahami by lacking the black caudal bar on postventral caudal margins v. evident in these species. It is distinct from the Japanese S. mitsukurii and the Mediterranean S. blainvillei by having body grey dorsally v. body dark grey to blackish dorsally in S. mitsukurii and body light reddish brown in S. blainvillei. Pelvic fins of Squalus bassi are located at the midline between the dorsal fins, while they are nearest second dorsal fin in S. montalbani, S. chloroculus and S. edmundsi and nearest to first dorsal fin in S. blainvillei. Origin of second dorsal fin is just posterior to the vertical line traced at pelvic-fin free rear tips in adults of Squalus bassi v. origin of second dorsal fin far behind the vertical line traced at pelvic-fin free rear tips in adults of S. mitsukurii, S. blainvillei and S. lalannei. Squalus bassi is distinct from S. mitsukurii, S. montalbani and S. lalannei by having a concave pectoral-fin posterior margin near its free rear tip v. pectoral-fin posterior margin straight in these three species. Squalus bassi is distinct from S. blainvillei and S. edmundsi by head length, 22•4–25•2% LT v. 19•8–22•3% LT for S. blainvillei and 25•6% LT for S. edmundsi. It can be further separated from S. mitsukurii by: shape of caudal fin, which exhibits a rectangular upper caudal lobe, caudal fork concave and dorsal and ventral caudal tips rounded v. subtriangular upper caudal lobe, caudal fork strongly raked and dorsal and ventral caudal tips conspicuously pointed in S. mitsukurii and more elongate eyes, their length 4•2–6•2% LT v. 3•5–4•0% LT in S. mitsukurii. Squalus bassi has more monospondylous and diplospondylous vertebrae than S. blainvillei (43–48, 69–75 for S. bassi v. 40–41, 67–68 for S. blainvillei). It has more precaudal vertebrae (86–89) than S. blainvillei (80–83), S. montalbani (84) and S. lalannei (67–69) and more total vertebrae (115–120) than S. blainvillei (107–109) and S. lalannei (93–95).

Teeth similar in both jaws, upper teeth smaller than lower teeth (Fig. 2); teeth unicuspid with cusp thick, short and oblique; mesial cutting edge straight; mesial heel rounded on lower jaw and notched on upper jaw; distal heel notched; apron conspicuously short and slender. Upper jaw with three series of functional teeth and two series on lower jaw in holotype. Upper teeth in holotype in 13–13 rows (13–13 in paratypes) and 11–12 (10–10) rows on lower jaw

Habitat

Marine; depth range: 159–591m depth

Distribuzione

South-eastern Atlantic and western Indian Oceans from southwards along the Western Cape, South Africa and extending to Mozambique.

Alimentazione

Bony fishes, cephalopods and crustaceans

Dimensioni

Maximum TL: 1100 mm (female), 960 mm (males); minimum size at maturity: 730 mm (female), 650 mm (males), size at birth: 210–300 mm

Riproduzione

Females have between 4–9 pups per litter.



Specie del genere Squalus

   
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