crossopterygian definition of crossopterygian in the Free Online Encyclopedia.

lobefin, common name for any of a group of lunged, fleshy-finned, bony fishes fish, limbless aquatic vertebrate animal with fins and internal gills. There are three living classes of fish: the primitive jawless fishes, or Agnatha; the cartilaginous (sharklike) fishes, or Chondrichthyes; and the bony fishes, or Osteichthyes.
..... Click the link for more information. , also called crossopterygians, that were dominant in the Devonian period and gave rise to amphibians amphibian, in zoology, cold-blooded vertebrate animal of the class Amphibia. There are three living orders of amphibians: the frogs and toads (order Anura, or Salientia), the salamanders and newts (order Urodela, or Caudata), and the caecilians , or limbless
..... Click the link for more information. . They had heavy, ungainly bodies and stumpy paired fins, the precursors of the limbs of four-footed animals. Known from their fossils, the lobefins were thought to be extinct until 1938, when a live coelacanth was caught in deep water off S Africa. Since then other specimens have been discovered in the Madagascar area. The coelacanths are a marine branch of the lobefins. The coelacanth discovered in 1938, Latimeria chalumne, is a brown to steel-blue fish 5 ft (150 cm) long, with circular, overlapping scales, a laterally flattened three-lobed tail, a spiny dorsal fin, and a vestigial lung. The fish give birth to live young. The coelacanth is the nearest living fish relative of the amphibians. In 1998 a closely related coelacanth, L. menadoensis, was discovered in Indonesia. Lobefins are classified in the phylum Chordata Chordata (kôrdā`tə,–dä`–)
..... Click the link for more information. , subphylum Vertebrata, class Osteichthyes, order Crossopterygii. See lungfish lungfish, common name for any of a group of fish belonging to the families Ceratodontidae and Lepidosirenidae, found in the rivers of South America, Africa, and Australia. Like the lobefins, the lungfishes are ancestrally related to the four-footed land animals.
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Bibliography

See S. Weinberg, A Fish Caught in Time (2000).

lobefin (redirected from crossopterygian)

Bibliography

lobefin
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