Author: Blainville, 1816
Field Marks:
Scyliorhinids without trilobate, barbeled anterior nasal flaps, labial furrows on lower jaw only, second dorsal much smaller than first.
Diagnostic Features:
Body not tadpole-shaped, moderately stout to slender and cylindrical or spindleshaped, tapering considerably to caudal fin; body firm and thick skinned, with well-calcified dermal denticles; stomach not inflatable; tail moderately long, length from vent to lower caudal origin between 3/5 to 3/4 of snoutvent length. Head slightly to moderately depressed, narrowly rounded and not wedge-shaped in lateral view; head short, less than 1/5 of total length in adults; snout short, less than 3/4 of mouth width, thick, and slightly flattened, bluntly pointed in lateral view; snout not expanded laterally, rounded-parabolic in dorsoventral view; ampullal pores not greatly enlarged on snout; nostrils not enlarged to moderately enlarged, with incurrent and excurrent apertures only slightly open to exterior; anterior nasal flaps more or less triangular, sometimes slightly elongated, without a prominent barbel, well separated from each other and ending somewhat anterior to mouth but close together and reaching it in S. canicula; internarial space 0.3 to 0.8 times in nostril width; nasoral grooves usually absent except S. canicula in which broad grooves are present; eyes dorsolateral on head, broad subocular ridges present below eyes; mouth angular or broadly arched, moderately long, with lower symphysis somewhat behind upper so that upper teeth are well-exposed in ventral view (except S. canicula, in which upper teeth are obscured by lower jaw); labial furrows present along lower jaw only, these short to moderately long; vestigial uppers occasionally prsent; branchial region not greatly enlarged, distance from spiracles to fifth gill slits 1/2 to 2/5 head length; gill slits lateral on head. Two dorsal fins present, with the second considerably smaller than the first; origin of first dorsal varying from over last half of pelvic bases to over pelvic free rear tips; origin of second dorsal over last third of anal base to slightly behind anal insertion; pectoral fins large, their width about as great or considerably greater than mouth width. Inner margins of pelvic fins more or less fused over claspers in adult males, forming a 'apron'; claspers short, relatively thick, and distally pointed or rounded, extending less than half their lengths behind the pelvic fin tips; anal fin moderately large but not greatly elongated, subequal to pelvic and first dorsal fins but much larger than second dorsal, its base length 1.3 to 2.4 times the second dorsal base; origin of anal well behind pelvic bases, and insertion separated from lower caudal origin by a space varying from half as long to slightly longer than the anal base; caudal fin short and fairly broad, between 1/4 to 1/5 to less than 1/5 of total length in adults. No crests of denticles on the caudal margins; supraorbital crests present on cranium. Colour pattern extremely variable, ranging from simple dark saddles, reticulating dark bars, or large dark spots on a light background to combinations of light and dark spots and saddles.
Remarks:
The arrangement of this genus follows Springer (1979), which in turn follows Springer's earlier treatments of the genus (Springer, 1966; Springer and Sadowsky, 1970).