Squalus formosus
White & Iglésias, 2011
Classification: Elasmobranchii Squaliformes Squalidae
Reference of the original description
Squalus formosus, a new species of spurdog shark (Squaliformes: Squalidae), from the western North Pacific Ocean. Journal of Fish Biology, 79(4), 954–968
Squalus formosus, a new species of spurdog shark (Squaliformes: Squalidae), from the western North Pacific Ocean. Journal of Fish Biology, 79(4), 954–968
Image of the original description
Image in copyright.
Image in copyright.
Description :
Citation: Squalus formosus White & Iglésias, 2011: In: Database of modern sharks, rays and chimaeras, www.shark-references.com, World Wide Web electronic publication, Version 11/2024
Short Description
A medium-sized species of Squalus of the ‘highfin megalops group’ is characterized by the following combination of characters: snout relatively short; first dorsal fin tall and upright, upper posterior margin almost straight; caudal fin with broad white posterior margin, no dark caudal bar; flank denticles tricuspid. These characters clearly differentiate this species from the three other sympatric Squalus species. Squalus formosus is morphologically closest to S. albifrons from eastern Australia but differs in the following characters: first dorsal fin with a distinct, broad white anterior margin (v. no distinct white marking); second dorsal fin height 5.7–6.4 v. 4.3–5.1% LT; first dorsal fin height 9.0–10.5 v. 7.7–8.9% LT, anterior margin 12.4–14.6 v. 10.9–12.7% LT; eye slightly larger 4.8–5.3 v. 4.4–4.8% LT. Squalus formosus can be further distinguished from other Squalus species in the following combination of characters: pre-second dorsal length 3.7–4.4 times pectoral-fin anterior margin; preoral length 2.2–2.3 times horizontal prenarial length; head length 4.0–4.7 times eye length; interorbital width 1.4–1.6 times horizontal preorbital length; posterior margin of second dorsal fin deeply concave; second dorsal-fin spine with a broad base; dorsal surface of head dark, sharply demarcated from paler ventral surface; 45–46 monospondylous centra, 94–95 precaudal centra, 123–124 total centra; adult maximum size at least 73 cm LT (Ref. 87791).
A medium-sized species of Squalus of the ‘highfin megalops group’ is characterized by the following combination of characters: snout relatively short; first dorsal fin tall and upright, upper posterior margin almost straight; caudal fin with broad white posterior margin, no dark caudal bar; flank denticles tricuspid. These characters clearly differentiate this species from the three other sympatric Squalus species. Squalus formosus is morphologically closest to S. albifrons from eastern Australia but differs in the following characters: first dorsal fin with a distinct, broad white anterior margin (v. no distinct white marking); second dorsal fin height 5.7–6.4 v. 4.3–5.1% LT; first dorsal fin height 9.0–10.5 v. 7.7–8.9% LT, anterior margin 12.4–14.6 v. 10.9–12.7% LT; eye slightly larger 4.8–5.3 v. 4.4–4.8% LT. Squalus formosus can be further distinguished from other Squalus species in the following combination of characters: pre-second dorsal length 3.7–4.4 times pectoral-fin anterior margin; preoral length 2.2–2.3 times horizontal prenarial length; head length 4.0–4.7 times eye length; interorbital width 1.4–1.6 times horizontal preorbital length; posterior margin of second dorsal fin deeply concave; second dorsal-fin spine with a broad base; dorsal surface of head dark, sharply demarcated from paler ventral surface; 45–46 monospondylous centra, 94–95 precaudal centra, 123–124 total centra; adult maximum size at least 73 cm LT (Ref. 87791).
Distribution
Pacific Ocean: Taiwan and Japan. Type specimens were collected from the fish landing site at Tashi (c. 24°50'S) in north-eastern Taiwan, but depth of capture unknown. Also recorded from waters off Kyushu (c. 32°N) and Shikoku (c. 33°20'N) (Chen et al., 1979).(Ref. 87791). Source: www.gbif.org
Pacific Ocean: Taiwan and Japan. Type specimens were collected from the fish landing site at Tashi (c. 24°50'S) in north-eastern Taiwan, but depth of capture unknown. Also recorded from waters off Kyushu (c. 32°N) and Shikoku (c. 33°20'N) (Chen et al., 1979).(Ref. 87791). Source: www.gbif.org
Biology
Subtropical
Subtropical
Habitat
Marine; pelagic
Marine; pelagic
Remarks
shark-references Species-ID=11148;
shark-references Species-ID=11148;