Squalus Linnaeus, 1758

Ebert, David A., White, William T., Ho, Hsuan-Ching, Last, Peter R., Nakaya, Kazuhiro, Séret, Bernard, Straube, Nicolas, Naylor, Gavin J. P. & De Carvalho, Marcelo R., 2013, An annotated checklist of the chondrichthyans of Taiwan, Zootaxa 3752 (1), pp. 279-386 : 285-287

Genus Squalus Linnaeus, 1758

Dogfishes / qḛé

Squalus Linnaeus, 1758: 233 . Type species: Squalus acanthias Linnaeus, 1758 , by subsequent designation of Gill, 1862: 39.

Squalus brevirostris Tanaka, 1917

Japanese Shortnose Spurdog / Ùḓqḛ

Squalus brevirostris Tanaka, 1917: 464 , pls. 129 (362–363), 130 (364). Holotype: ZUMT 7630 , male 430 mm TL, probably from Shimonoseki , Japan, collected from the Tokyo fish market.

Local synonymy: Squalus brevirostris: Chen, 1948: 42 ; Liang, 1951: 3; White & Iglésias, 2011: 954, fig. 4a. Squalus megalops: Teng, 1962: 144 , fig. 36; Chen, 1963: 89, fig. 27; Shen, 1984a: 66, fig.; Chen & Yu, 1986: 112; Joung et al., 1989: 241 (in key); Chen & Joung, 1993: 41, pl. 3; Shen & Wu, 2011: 81, fig.

Taiwan voucher material: (7 spec.) CAS 235390 , female 435 mm TL, Da-xi, 22 May 2005 ; CSIRO H 6923-29 (GenBank accession EF 539300 ), unsexed 440 mm TL , CSIRO H 6923-30 (GenBank accession EF 539299 ), female 446 mm TL ; CSIRO H 6923-31 (GenBank accession EF 539298 ), female 435 mm TL, Da-xi, 22 May 2005 ; CAS 236071 (tissue accession GN10047 ), adult male 390 mm TL ; AMNH 258171 (tissue accession GN10048 ), adult male 393 mm TL, Da-xi, 14 Mar 2012 ; MNHN 2013-0500 (tissue accession GN10075 ), female 503 mm TL Da-xi, 15 Mar 2012 .

Remarks: Commonly landed at s in eastern and southern Taiwan. Very similar to Squalus megalops ( Macleay, 1881) and often placed in the synonymy of this species; a detailed taxonomic examination of the Squalus megalops complex in the Indo-West Pacific is required to help clarify the status of S. brevirostris .

Conservation status: Data Deficient.

Squalus formosus White & Iglésias, 2011

Taiwan Spurdog / Ớ ǡḁqḛ

Squalus formosus White & Iglésias, 2011: 954 , figs 1–3. Holotype: CSIRO H 6816-01 , adult male 734 mm TL, 24°50' N, 121°22' E, Ta-Shi fish market, 11 Jul 2007.

Local synonymy: Squalus blainvillei: Compagno, 1984: 115 , fig.; Joung et al. 1989: 241, fig. 4; Chen & Joung, 1993: 41, pl. 3; 2011: 81, fig. Squalus blainville: Chen & Yu, 1986: 111 ; Shao et al., 2008: 237. Squalus formosus: White & Iglésias, 2011: 954 , figs 1–3. Squalus sp. 1 : Nakabo, 2002: 156, fig.

Taiwan voucher material: Holotype : CSIRO H 6816-01 , adult male 734 mm TL, Da-xi, 11 Jul 2007 . Other specimens (6): MNHN 2008–1939 , juvenile female 514 mm TL, Da-xi, 11 Jul 2007 ; CSIRO H 6292-10 (GenBank accession EF 539330 ), juvenile female 336 mm TL, Da-xi, 21 May 2005 ; CAS 236072-1 (tissue accession GN9922 ), 693 mm TL, adult male, Da-xi, 13 March 2012 ; CAS 236072-2 (tissue accession GN9923 ), 734 mm TL, adult male, Da-xi, 13 March 2012 ; HUMZ 213800 (tissue accession GN10045 ), 569 mm TL, juvenile male ; HUMZ 213801, 562 mm TL, juvenile male, Da-xi, 14 Mar 2012 .

Remarks: Commonly landed at some fish markets in eastern and southern Taiwan. Previously referred to as Squalus blainvillei ( Risso, 1827) by most authors, but recently described as a new species endemic to Taiwanese and Japanese waters; most similar to Squalus albifrons Last, White & Stevens, 2007 from eastern Australia. This species belongs to a highfin- megalops subgroup which are characterised by a tall, upright first dorsal fin, a white posterior margin on caudal fin, and a short snout.

Conservation status: Not Evaluated.

Squalus japonicus Ishikawa, 1908

Japanese Spurdog / ƂÂqḛ

Squalus japonicus Ishikawa, 1908: 71 . Syntypes: two males (one adult 700 mm TL), Sagami Bay , collected from Tokyo fish market, and one female from Kagoshima, whereabouts unknown ( Chen et al., 1979; Eschmeyer, 2012).

Local synonymy: Squalus fernandinus: Chen, 1963: 88 (in part). Squalus japonicus: Compagno, 1984: 117 , fig.; Joung et al., 1989: 241 (in key); Chen & Joung, 1993: 41, pl. 3; Shen & Wu, 2011: 81, fig.

Taiwan voucher material: (7 spec.) CSIRO H 6294-26 , male 456 mm TL , CSIRO H 6294-27 , female 380 mm TL , CSIRO H 6294-31 , female 571 mm TL ; UF 148932, male embryo 247 mm TL, Da-xi, 23 May 2005 ; MNHN 2013- 0502 (tissue accession GN10054 ), juvenile male 490 mm TL ; MNHN 2013-0503 (tissue accession GN10055 ), juvenile male 369 mm TL ; MNHN 2013-0504 (tissue accession GN10056 ), juvenile male 459 mm TL; Nan-fangao, 14 Mar 2012 .

Remarks: Commonly landed at some s in eastern and southern Taiwan. Western North Pacific populations of this species were previously referred to as S. sucklii by Garman (1913), S. fernandinus by Bigelow & Schroeder (1957) and Fowler (1941), and S. mitsukurii by Jordan & Fowler (1903); S. japonicus resurrected as a valid species by Chen et al. (1979). Previously considered to range from Japan to northern Australia but now considered a western North Pacific endemic, with Philippine, Indonesian and Australian populations recently described as a separate species, Squalus nasutus Last, Marshall & White, 2007 .

Conservation status: Data Deficient.

Squalus montalbani Whitley, 1931

Shortspine Spurdog / ắkqḛ

Squalus montalbani Whitley, 1931: 310 . Holotype: USNM 70256 , juvenile male 311 mm TL, off Sombrero Island , western coast of Luzon Island, 13°45’15”N, 120°46’30”E, Philippines, Albatross station 5111, depth ca. 425 m.

Local synonymy: Squalus mitsukurii: Nakamura, 1936: 42 , pl. 16, fig. 2; Chen, 1948: 42; Compagno, 1984: 121, fig.; Joung et al., 1989: 241 (name only in key to genus Squalus from Taiwan); Chen & Joung, 1993: 41, pl. 3; Shen & Wu, 2011: 82, fig. Squalus fernandinus: Chen, 1963: 88 (in part); Chen & Yu, 1986: 111.

Taiwan voucher material: (7 spec.) CAS 236073 (tissue accession GN10097 ), juvenile male 597 mm TL, Donggang, 16 Feb 2012 ; CSIRO H 7403-02 (tissue accession GN10173 ), female 651 mm TL , MNHN 2013-0505 (tissue accession GN10172 ), off Kaohsiung, 22°32′N, 120°07′E, 320 m depth, 21 March 2012 ; NMMB-P 9275 , NMMB- P9262, Dong-gang, 18 Sep 2008 ; NMMB-P 15362, 590 mm SL, Dong-gang, 19 May 2011 ; NMMB-P 15785, 835 mm TL, unknown location.

Remarks: Commonly landed at some fish markets in eastern and southern Taiwan. Previously considered to be S. mitsukurii , but recent morphological and molecular taxonomic work has indicated that S. montalbani ranges from temperate and tropical Australia, north to Indonesia and the Philippine Islands, and now its distribution can be extended to Taiwan; belongs to the mitsukurii subgroup which are characterised by a relatively low, raked first dorsal fin, a posterior margin of caudal fin white with a broad black bar centrally, and a moderately long snout. Squalus mitsukurii previously considered to be wide-ranging now appears likely to be restricted to the waters of the Koreas, Japan, and Mainland China.

Conservation status: Data Deficient.

Squalus suckleyi ( Girard, 1854)

North Pacific Spiny Dogfish / Ŕkqḛ

Spinax (Acanthias) suckleyi Girard, 1854: 196 . Neotype: CAS 227267 , adult male 674 mm TL, Hood Canal , Puget Sound, Washington, USA, 30 m depth, 47°22′N, 123°05′W, 3 Aug 2007.

Local synonymy: Squalus sucklii: Fowler, 1930: 495 ( Formosa) . Squalus suckleyi: Fowler, 1941: 258 ( Formosa) ; Chen, 1948: 42. Squalus acanthias: Chen, 1963: 87 (THUP 2066, 225 mm TL); Chen & Yu, 1986:111.

Taiwan voucher material: (1 specimen) NMMB-P 4293 , Dong-gang , Pingtung, 1 Apr 1960 .

Remarks: Known from few records off Taiwan, with no confirmed specimens recorded since 1960 from Taiwanese waters. Previously considered a junior synonym of Squalus acanthias Linnaeus , but a recent taxonomic study revealed that the North Pacific population is a separate species and Squalus suckleyi was resurrected for the North Pacific species ( Ebert et al., 2010). Taiwan likely represents the most southerly distribution of this species in the western North Pacific, with the limited records suggesting it is either rare in Taiwanese waters or has been extirpated.

Conservation status: Not Evaluated.