Zameus, Jordan & Fowler, 1903

Romanov, Evgeny V., Bach, Pascal, Rebik, Sergei T., Turc, Alexandre Le & Séret, Bernard, 2013, First pelagic record of the velvet dogfish Zameus squamulosus (Günther, 1877) (Squaliformes) from the southwestern Indian Ocean and some notes on its regional distribution, Zoosystema 35 (1), pp. 11-23 : 15-17

Genus Zameus Jordan & Fowler, 1903

Zameus squamulosus ( Günther, 1877) ( Figs 1 ; 3 )

Synonyms: Centroscymnus obscurus Vaillant, 1888 , Expéditions scientifiques du Travailleur et du Talisman pendant les années 1880, 1881, 1882, 1883. Poissons, 67-68, pl. 2, fig. 2a-e. Holotype: Muséum national d’Histoire naturelle, Paris, MNHN- 84-388, 590 mm female, ‘côtes du Soudan’, 1400-1435 m.

Other combinations: Scymnodon squamulosus ( Regan, 1908) , Scymnodon obscurus Bigelow and Schroeder (1957) .

MATERIAL EXAMINED. — Southwestern Indian Ocean , 23°17’S, 52°17’E, 25. V.2011, ♀, 672 mm TL, MNHN 2012-0188 . — Japan, off Imosiina, holotype of Centrophorus squamulosus Günther, 1877 , adult ♀, 670 mm TL, NHMUK 1880-5-1:1. — Broken Ridge, southeastern Indian Ocean, 04.III.2008, 30°55’0S, 93°26’0E, 1027-1122 m, ♀, 830 mm TL (coll. STR) ; 30°55’0S, 94°02’0E, 1138- 1152 m, 05.III.2008, unsexed, 600 mm TL (coll. STR); 30°59’0S, 93°47’0E, 1048-1134 m, 12.III.2008, ♀, 730 mm TL, unsexed, 810 mm TL (coll. STR); 30°04’0S, 93°56’0E, 1062-1169 m, 17.III.2008, gravid ♀, 900 mm TL (coll. STR). — Southwest Indian Ocean Ridge , 34°13’0S, 44°14’0E, 1414-1456 m, 04.IV.2008, unsexed, 620 mm TL (coll. STR) ; 34°30’0S, 44°43’0E, 1278-1556 m, 09.IV.2008, ♂, 530 mm TL (coll. STR); 34°26’0S, 44°33’0E, 1450-1528 m, 21.IV.2008, unsexed, 830 mm TL (coll. STR).

DISTRIBUTION. — Worldwide over continental slopes and undersea ridges in tropical and temperate waters.

DESCRIPTION

Individual caught in pelagic environment (MNHN 2012-0188) is a medium-sized, black-coloured shark with bright green eyes. It was alive at the time it was taken onboard but quickly died afterwards. Body proportions of our specimen are shown in Table 1. Dental formula: 27-27/21-21. Our specimen well corresponds to the original description given by Günther (1877) and later by Yano & Tanaka (1984). Body measurements are within the ranges presented in other studies, except PP2, SVL (slightly higher than reported earlier) and trunk width (slightly lower) ( Table 1). The latter could be explained by post-defrosting deformation.

Figures

FIG. 1. — Individuals of Zameus squamulosus (Günther, 1877) caught in the pelagic and demersal environment: A, MNHN 2012-0188, female (672 mm TL) caught on a pelagic longline set on 25 May 2011 in the southwestern Indian Ocean (black bar at the ruler is equal to 5 cm); B, female caught on a demersal longline set on 5 March 2008 in the southeastern Indian Ocean (see Table 2 for details) (ruler length is 30 cm).

FIG. 3. — Dermal denticles from the trunk region of Zameus squamulosus (Günther, 1877) caught in the pelagic and demersal environment: A, MNHN 2012-0188, female, 676 mm TL; B, female from demersal zone of the southeastern Indian Ocean shown on the Figure 1B. Scale bar: 1 mm.