Glaucostegus Bonaparte, 1846

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 : 348-350

Genus Glaucostegus Bonaparte, 1846

Spiny Guitarfishes / Ợḙůḍé

Glaucostegus Bonaparte, 1846: 14 . Type species: Rhina cemiculus Geoffroy St. Hillaire, 1817 , by subsequent designation.

? Glaucostegus granulatus ( Cuvier, 1829)

Giant Guitarfish / ķÚỢḙůḍ

Rhinobatus granulatus Cuvier, 1829: 396 . Syntypes: MNHN 0000-1253 (female 425 mm TL) & MNHN 0000-1254 (female 310 mm TL), Coromandel , Pondicherry, India.

Local synonymy: Scobatus granulatus: Shen, 1988: 5 .

Taiwan voucher material: (1 specimen) NTUM 03789 , 1 specimen from Ma-gung ( Shen, 1988) .

Remarks: Shen (1988) listed a specimen ( NTUM 03789) only, but we could not find it during the 2012 survey. Chu (1960) listed 4 specimens 540–865 mm TL from off the mainland of China with catalogue numbers, but these specimens could not be confirmed as G. granulatus . We could find no confirmed records of G. granulatus from the Pacific as all specimens purported to be this species were found to be a misidentification of G. typus (Bennett, 1830) , a species that does appear to in this region. The issue is currently under investigation by PRL and BS.

Conservation status: Vulnerable.

? Glaucostegus microphthalmus ( Teng, 1959f)

Smalleyed Guitarfish / ṁḊḙůḍ

Rhinobatos microphthalmus Teng, 1959f: 10 . Holotype: TFRI 3089 , female 1215 mm TL, from Keelung, Taiwan, 17 March 1957.

Local synonymy: Rhinobatos microphthalmus: Chen, 1948: 24 , 35; Teng, 1959f: 11, 90, fig. 6, pl. II, fig. 6; Chen & Chung, 1971: 15; Chen & Joung, 1993: 73; Chen, 2004: 24; Ho & Shao, 2011: 20.

Taiwan voucher material: Holotype: TFRI 3089 (lost). No additional material was examined during the 2012 survey.

Remarks: The type specimen for this species was collected at the Keelung, but it could have been landed from outside Taiwanese waters since a second specimen of this species from Vietnam was landed at Kaohsiung according to H.-C. Yang (pers. comm.). This species is possibly a synonym of G. typus .

Conservation status: Data Deficient.

Rhinobatos formosensis Norman, 1926

Taiwan Guitarfish / Ớ ḙůḍ

Rhinobatos formosensis Norman, 1926: 4 . Syntypes, BMNH 1862.12.6.69-70 (2, 625– 630 mm TL), Taiwan.

Local synonymy: Rhinobatos formosensis: Norman, 1926: 4 ; Fowler, 1941:307; Chen, 1948: 24, 35; Teng, 1959f: 7, fig. 3, pl. I, fig. 3 (TFRI 2565, male, 556 mm, Keelung); Chen & Chung, 1971: 12, fig. 9 (THUP 11847, 3 spec., 377-645 mm, Taichong); Shen, 1988: 5 (NTUM 6680, Ta-Sahi, NTUM 6802, Penghu); Chen & Joung, 1993: 72, fig. 7; Chen, 2004: 23; Shao et al., 2008: 237; Ho & Shao, 2011: 21.

Taiwan voucher material: TFRI 2565, male, 556 mm, Keelung. No additional material was examined during the 2012 survey. Several specimens from the NMMB collection were provisionally identified as R. formosensis during the 2012 survey, but their morphometrics and meristics appear to fit within the range of variation of R. schlegelii .

Remarks: The taxonomic status of this species is currently under investigation, but it is likely to be a junior synonym of Rhinobatos schlegelii Müller & Henle, 1841 .

Conservation status: Data Deficient.

Rhinobatos hynnicephalus Richardson, 1846

Ringstraked Guitarfish / ŌĠḙůḍ

Rhinobatus hynnicephalus Richardson, 1846 , Rep. Brit. Ass. Adv. Sci. 15th meeting. No types known. China seas.

Local synonymy: Rhinobatus polyophthlamus: Nakamura, 1936: 48 . Rhinobatos hynnicephalus: Chen, 1948: 25 , 36; Teng, 1959f: 10, 90, fig. 5, pl. II, fig. 6 (TFRI 2761, male 458 mm TK, Keelung); Chen & Chung, 1971: 14, fig. 11 (THUP 469, 4 spec., 425-534 mm TL, Tai-Chong); Shen, 1988: 5 (NTUM 36, 2 spec., Ma-Kung); Chen & Joung, 1993: 73, fig. 8; Chen, 2004: 24 (TFRI PB 8302272, Peng-Hu); Shao et al., 2008: 237.

Taiwan voucher material: Four specimens from THUP, now in the NMMB (Accession numbers 6483 & 6494) and 16 specimens (395–650 mm TL) collected in 2011 now in the NMMB collections. NMMB-P uncatalogued (tissue accession GN10242 ), NMMB-P uncatalogued (tissue accession GN10243 ), NMMB-P uncatalogued (tissue accession GN10244 ), Da-xi, 23 Oct 2011 .

Remarks: Specimens in preservative often lose their distinctive markings leading to confusion with R. schlegelii .

Conservation status: Near Threatened.

Rhinobatos schlegelii Müller & Henle, 1841

Brown Guitarfish / ệkḙůḍ

Rhinobatos schlegelii Müller & Henle, 1841: 123 , pl. 42. Lectotype: RMNH D2680 (dry), Paralectotypes (8 including 6 dry and 2 in alcohol) RMNH D2681, D2684–2687, D2689 and 4225; Japan.

Local synonymy: Rhinobatos schlegelii: Günther, 1870: 446 ; Jordan & Evermann, 1902: 318; Fowler, 1941:308; Chen, 1948: 24 & 36; Teng, 1959f: 8, 89, fig. 4, pl. II, fig.4 (TFRI 2507, female 466 mm TL, Keelung); Chen & Chung, 1971: 13, fig. 10 (THUP 145, 7 spec. 233-442 mm, Penghu); Shen, 1988: 407 (NTUM 6681, Ta-Shi); Chen & Joung, 1993: 73, fig. 8; Chen, 2004: 24 (THUP PB 8105055, 589 mm TL).

Taiwan voucher material: AMNH 258309 (tissue accession GN10039 ) , adult male 646 mm TL, Da-xi, 14 Mar 2012; NMMB-P uncatalogued (tissue accession GN10256 ) , NMMB-P uncatalogued (tissue accession GN10257 ) , NMMB-P uncatalogued (tissue accession GN10252 ), Da-xi, 23 Oct 2011. In addition, one of us ( BS) examined about 25 specimens from the NMMB collections.

Remarks: The status of the Taiwanese Rhinobatos schlegelii is under revision by BS and PRL.

Conservation status: Data Deficient.