The sand devil's flattened body and enlarged pectoral and pelvic fins give it a ray-like appearance.

The diet of the sand devil consists mainly of small teleost fishes and squid, which are captured via ambush attack.

Females have a multi-year reproductive cycle and give birth to 4–25 pups in spring or early summer, following a 12-month gestation period.

French naturalist Charles Alexandre Lesueur described the sand devil in an 1818 volume of Journal of the Academy of Natural Sciences of Philadelphia.

Lesueur based his account on an adult male 1.2 m (3.9 ft) long caught off the eastern United States, and named the species in honor of André Marie Constant Duméril.

[2] Phylogenetic analysis, based on mitochondrial DNA, has concluded that the sand devil and the Pacific angel shark (S. californica) are sister species.

[3] The sand devil has a flattened, moderately narrow body with greatly enlarged pectoral and pelvic fins.

The dorsal coloration varies from greenish or bluish gray to reddish brown, with a scattering of small, darker spots and sometimes irregular splotches; the underside is uniformly pale.

[4][5] The sand devil is found in the northwestern Atlantic Ocean from Massachusetts to the Florida Keys, where it is fairly common.

As a result, ranges of deep-water shark species are often considered continuous across broad expanses despite records of occurrence, in many cases, being spatially fragmented.

It tends to select prey approximately 50–60% as long as its mouth is wide; this size is consistent with what is predicted from optimal foraging theory to yield the most efficient rate of energy return.

[7] In the northern Gulf of Mexico, the most important prey species are Atlantic croaker (Micropogonias undulatus), longspine porgy (Stenotomus caprinus), spot croaker (Leiostomus xanthurus), Gulf butterfish (Peprilus burti), red goatfish (Mullus auratus), dwarf goatfish (Upeneus parvus), and longfin inshore squid (Doryteuthis pealeii).

Mating occurs in the spring; adult males have spines on the outer margins of their pectoral fins, which may help in gripping the female during copulation.

Its common name refers to its habit of snapping vigorously at fishery workers when caught, and even out of the water it is capable of lunging upwards to bite.