Elasmobranchii (sharks and rays) >
Squaliformes (Sleeper and dogfish sharks) >
Somniosidae (Sleeper sharks)
Etymology: Somniosus: Latin for sleepy, reflecting Lesueur’s surmise that these sharks are slow or sluggish because of their relatively small fins (hence the name sleeper sharks). (See ETYFish); microcephalus: micro-, from mikros (Gr.), small; cephalus, from kephale (Gr.), head, allusion not explained, perhaps referring to its short, rounded snout compared with other sharks then included in the catch-all genus Squalus. (See ETYFish).
More on authors: Bloch & Schneider.