Cephaloscyllium fasciatum Chan 1966

Schaaf-Da, Jayna A. & Ebert, David A., 2008, A revision of the western North Pacific swellsharks, genus Cephaloscyllium Gill 1862 (Chondrichthyes: Carcharhiniformes: Scyliorhinidae), including descriptions of two new species, Zootaxa 1872, pp. 1-28 : 13-14

publication ID	https://doi.org/ 10.5281/zenodo.183986
DOI	https://doi.org/10.5281/zenodo.5613447
persistent identifier	https://treatment.plazi.org/id/0398879E-FFFB-FFA2-FF49-B0DCFD1AF95F
treatment provided by	Plazi
scientific name	Cephaloscyllium fasciatum Chan 1966
status

Treatment

Cephaloscyllium fasciatum Chan 1966 View in CoL

( Fig. 11 View FIGURE 11 , 5 View FIGURE 5 c, 7c; Table 2 View TABLE 2 )

Cephaloscyllium fasciatum Chan 1966: 232 View in CoL , Figs. 6 View FIGURE 6 and 7 View FIGURE 7 , pl. III; Springer 1979: 39; Compagno 1984: 297; Compagno et al. 2005a: 216, pl. 36.

Type Series and Locality. Holotype, BMNH 1965.8.11.1, maturing female, 421 mm TL, off Cape Bantagan, Vietnam, 15°55.7'N, 109°18.5'E, in 205–315 m on soft mud bottom, collected on 16 September 1963. Paratypes, BMNH 1965.8.11.2, juvenile male, 246 mm TL; BMNH 1965.8.11.3, juvenile male, 236 mm TL; BMNH 1965.8.11.4, juvenile male, 232 mm TL; BMNH 1965.8.11.5, juvenile female, 224 mm TL; same locality as holotype.

Diagnosis. Body comparatively slender; head short; a dwarf species. Snout short, moderately flattened, broadly rounded in dorsoventral view; anterior nasal flaps not overlapping mouth posteriorly, narrowly lobate, inner margin with a deep notch. Color pattern of a light grayish-brown ground color with dark brown lines formed into loops, open-centered saddles, reticulations and circles, with some small dark spots dorsally and laterally in adult only.

Description. Proportional dimensions in percentage of TL are shown in Table 2 View TABLE 2 . Head short, its length 0.23 (0.27) times precaudal length; pre-pectoral length 17.1 (20.1)% TL. Snout moderately flattened, broadly rounded, and short; preorbital length 0.06 (0.06) times in head length. Eye small, its horizontal eye length 3.6 (4.9)% TL; cat-like. Spiracle small, its diameter 0.88 (0.79) times horizontal eye length. Gill openings very small, vertical length of first gill opening 2.1 (1.8)% TL. Mouth wide, its width 11.8 (10.5)% TL; labial furrows absent. Nostrils large, internarial distance 0.23 (0.31) times mouth width; anterior nasal flaps elongate, lobed, with deep notch on inner margin, not overlapping mouth posteriorly. First dorsal fin small; first dorsalfin height 0.66 (0.67) in base; origin behind half of pelvic-fin base; pre-first dorsal length 53.2 (45.8)% TL. Second dorsal fin small, much smaller than first; second dorsal-fin height 0.44 (0.43) times base; second dorsal-fin height 0.45 (0.46) in first dorsal-fin height; pre-second dorsal length 67.6 (60.1)% TL. Pectoral fins relatively large and broad; greatest length 12.0 (12.1)% TL, base 0.63 (0.64) times greatest length. Pelvic fin small, its base 7.5 (7.3)% TL; inner margin 0.40 (0.43) in base. Anal fin large, slightly larger than second dorsal fin; height 0.37 (0.47) in base; second dorsal-fin height 0.82 (0.66) times anal-fin height. Caudal fin broad, asymmetrical, with subterminal notch; dorsal-lobe length 23.4 (22.5)% TL; ventral-lobe length 9.8 (10.5)% TL.

Body firm, thick-skinned, with well calcified dermal denticles; dermal denticles with a broad disc connected at a slant to a four-pointed base. Teeth very small and numerous; similar in both jaws; three cusps in adult males; numerous distinct ridges running from base toward cusp. Holotype with 58 teeth on upper jaw, 56 on lower jaw. Vertebral counts for holotype (BMNH 1965.8.11.1): total vertebrae 120, monospondylous 45, diplospondylous 75, caudal 43, and precaudal 77. Vertebral counts for mm paratype (BMNH 1965.8.11.5): total vertebrae 118, monospondylous 45, diplospondylous 73, caudal 40, and precaudal 78.

Size and sexual maturity. According to the literature and specimens studied, size at maturity for males 360 mm, and less than 421 mm for females; maximum size at least 421 mm ( Chan 1966, Compagno et al. 2005a).

Coloration. Light grayish-brown background; dark brown lines formed into loops, open-centered saddles, reticulations and circles, with a few small dark spots dorsally and laterally (juveniles lack spots); ventral side of head and abdomen lightly spotted; no white or light spots on the body in adults; 4–5 pre-first dorsal fin saddles.

Comparison with other species. Morphometric data are presented in Table 2 View TABLE 2 . Cephaloscyllium fasciatum has a very distinct color pattern that easily distinguishes it from other swellsharks, despite the multitude of new species recently described for this genus. We recognize that C. fasciatum may or may not have a lateral blotch, but never is the blotch large, dark and solid like that of C. circulopullum or C. sarawakensis . The dwarf size of C. fasciatum , along with the color pattern and lobate anterior nasal flap, can also help to distinguish it from other WNP Cephaloscyllium .

Remarks. This redescription of C. fasciatum is based on the holotype specimen (BMNH 1965.8.11.1) and one paratype specimen (BMNH 1965.8.11.5) loaned from BMNH. According to the Philippine Checklist of Chondrichthyes ( Compagno et al. 2005b) only one swellshark is mentioned. It is now known that the C. sp. 1 referred to in the Checklist is a large, undescribed swellshark (L.J.V. Compagno, pers. comm.).

Distribution. Cephaloscyllium fasciatum has been verified from the western Pacific, specifically Vietnam, China (Hainan Island), northwestern Australia ( Compagno et al. 2005a), and probably the Philippines although accounts need to be verified (L.J.V. Compagno, pers. comm.).

Etymology. The species was named after the Latin fasciata for banded, referring to the variegated color pattern of open saddles and circles with connecting dark lines.

Common name. Reticulated swellshark