4866 x 3662 px | 41,2 x 31 cm | 16,2 x 12,2 inches | 300dpi
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Chimaeras are cartilaginous fish in the order Chimaeriformes. They are related to the sharks and rays, and are sometimes called ghost sharks, ratfish (not to be confused with the rattails), or rabbitfishes. Chimaeras live in temperate ocean floors down to 2, 600 metres (8, 500 ft) depth. They have elongated, soft bodies, with a bulky head and a single gill-opening. They grow up to 150 centimetres (4.9 ft) in adult body length, although some also have a lengthy tail. In many species, the snout is modified into an elongated sensory organ. Like other members of the class Chondrichthyes, chimaeras have a skeleton constructed of cartilage. Their skin is smooth and lacks scales, and their color can range from black to brownish gray. For defense, most chimaeras have a venomous spine located in front of the dorsal fin. Chimaeras resemble sharks in some ways: they employ claspers for internal fertilization of females and they lay eggs with leathery cases. However, unlike sharks, male chimaeras also have retractable sexual appendages on the forehead and in front of the pelvic fins. They lay eggs in spindle-shaped leathery cases. They also differ from sharks in that their upper jaws are fused with their skulls and they have separate anal and urogenital openings. They lack the many sharp and replaceable teeth of sharks, having instead just three pairs of large permanent grinding tooth plates Scientific classification Kingdom: Animalia Phylum: Chordata Class: Chondrichthyes Subclass: Holocephali Order: Chimaeriformes Families Callorhinchidae Chimaeridae Rhinochimaeridae
