A relatively small group of elongate cartilaginous fishes with soft smooth bodies, large heads covered in prominent sensory canals, a single gill opening on each side and teeth fused into beak-like tooth plates.
Chimareas have large pectoral fins, two dorsal fins and a low anal fin joined to a low caudal fin that often terminates in a long filament. Most species have a stout venomous spine at the beginning of the first dorsal fin. They grow to about 1.5 m.
Although a few species are found inshore, most live near the bottom on the continental shelf and slope in depths to more than 2600 m.
Like sharks and rays, fertilisation is internal via male claspers (modified pelvic fins). Adult males have extra sexual claspers on their head and in front of their pelvic fins to hold the females during copulation. Females lay leathery egg cases.
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