Distribution:
Atlantic, Indian, and Pacific
Habitat:
Marine; tropical to warm temperate waters
Remarks:
Distributed circumglobally in tropical to warm temperate waters, Sleeper rays have small groove around mouth, short jaws, weak protractile, and a single dorsal fin. 
This family comprises five genera, Crassinarke, Heteronarce, Narke, Temera, and Typhlonarke, with a 11 species. 
References: Nelson 2006