[Bigelow and Schroeder, 1948 p. 295.]
[Garman, 1913 pl. 2, figs. 1-4.]
This little shark is separable from any other carcharhinid that has yet been reported from the Gulf of Maine or that is likely to be, by its upper and lower teeth which are perfectly smooth along the edges from tip to base, combined with a so-called "labial furrow" of considerable length running forward along each side of each jaw from the corner of the mouth toward the nostril. This last character, while not conspicuous, is a precise one.
The trunk is slender, highest about at the first dorsal fin, tapering both fore and aft. The snout varies rather widely in length and in bluntness at the tip. The point of origin of the first dorsal fin [page 41] is about over the inner corners of the pectorals when the latter are laid back; its height is about one-half as great as the distance from the tip of the snout to the level of the origin of the pectorals. The second dorsal is only about one-quarter as high as the first; its point of origin is about over the mid-point of the base of the anal fin; the anal is a little larger than the second dorsal. The tail fin occupies about one-quarter of the total length of the shark; its lower lobe (measured along the anterior edge) is a little less than one-half as long as the upper lobe, the rear edge of which is deeply notched near the tip. The pectoral fins are smaller relatively than in any other local species of this family, their length, armpit to tip, being only a little greater than the height of the first dorsal fin. The teeth are alike in shape in the two jaws, sharp-pointed and smooth edged; those in the center of the mouth are symmetrical and erect, but those along the sides have weakly concave inner margins, but deeply notched outer margins, and are increasingly oblique toward the corners of the mouth.
Brown to olive gray above, with the dorsal and caudal fins more or less dark edged; white below and along the rear margins of the pectorals.
Mature specimens are commonly between 26 and 30 inches long; a few grow to 36 inches.
Both sides of the tropical-subtropical Atlantic; Morocco to Cameroon and the Cape Verde Islands in the east; Uruguay to North Carolina in the west; occasional to Woods Hole, and as a stray to the Bay of Fundy.
Early reports of it from Newfoundland were based on a misconception.