Chimaera

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Chimaeras
Fossil range: Devonian–Recent
Hydrolagus colliei
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Holocephali
Order: Chimaeriformes
Families

See text for families, genera and species.

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 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 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. 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.

Contents

[edit] Albino Puget Sound ratfish

A rare albino Puget Sound ratfish was discovered near Whidbey Island, Washington. It is the only pure albino among the 7.2 million specimens in the University of Washington's fish collection. [1]

[edit] Gallery

[edit] Classification

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. Chimaeras also have some characteristics of bony fishes.

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

Elephantfish, Callorhinchus callorynchus
Elephantfish, Callorhinchus callorynchus

Family Callorhinchidae

Chimaera monstrosa
Chimaera monstrosa

Family Chimaeridae

Smalleyed rabbitfish, Hydrolagus affinis
Smalleyed rabbitfish, Hydrolagus affinis

Family Rhinochimaeridae

[edit] References

  1. ^ Scientists discover rare albino ratfish
  2. ^ Quaranta et al. (2006). "A new species of chimaeroid, Hydrolagus alphus sp. nov. (Chimaeriformes: Chimaeridae) from the Galapagos Islands". Zootaxa 1377: 33-45.