Chimaera

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Other meanings, including the ancient placename Chimaera, are based on the mythological creature Chimera; see the disambiguation page Chimera for a full list.

{{Taxobox | color = pink | name = Chimaeras | fossil_range = Devonian–Recent | image = Hydrolagus02 600.jpg | image_width = 240px | image_caption = Hydrolagus sp. | regnum = Animalia | phylum = Chordata | classis = Chondrichthyes | subclasses = Holocephali | ordo = Chimaeriformes | subdivision_ranks = Families | subdivision = Callorhynchidae
Chimaeridae
Rhinochimaeridae
See text for genera and species. }} Chimaeras are cartilaginous fishes in the order Chimaeriformes. They are related to the sharks and rays, and are sometimes called ghost sharks.

Chimaeras live in temperate ocean floors and grow up to two meters long. 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 poisonous 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. They differ from sharks in that their upper jaws are fused with their skulls; they have separate anal and urogenital openings; and they lack the many sharp and replaceable teeth of sharks, having instead a few large permanent grinding tooth plates.

Classification

Image:Chimaerapup.jpg In some classifications the chimaeras are included (as subclass Holocephali) in the class Chondrichthyes of cartilaginous fishes; in other systems this distinction may be raised to the level of class.

There are about forty species in six genera and three families:

Family Callorhinchidae

Family Chimaeridae

Family Rhinochimaeridae

References

es:Chimaeriformes fr:Holocephali nl:Zeekatten no:Helhodefisker pl:Zrosłogłowe ru:Цельноголовые zh:银鲛目