- any fish of the group Crossopterygii, extinct except for the coelacanth, regarded as being ancestral to amphibians and other land vertebrates.
- pertaining to or resembling a crossopterygian.
Origin of crossopterygian
Examples from the Web for crossopterygian
Historical Examples of crossopterygian
These are found in the garpike and in many genera of extinct Ganoid and Crossopterygian fishes.
In every modern Dipnoan, Crossopterygian, and Ganoid the air-bladder has an effective pneumatic duct.
It is not unlikely that the Crossopterygian gave rise to Amphibian and Dipnoan alike.
In the archaic tail, enameled scales, and cartilaginous skeleton the Crossopterygian shows its affinity with its Dipnoan ancestry.
The Ganoid differs from the Crossopterygian in having the basal elements of the paired fins small and concealed within the flesh.
- any bony fish of the subclass Crossopterygii, having fleshy limblike pectoral fins. The group, now mostly extinct, contains the ancestors of the amphibiansSee also coelacanth
- of, relating to, or belonging to the Crossopterygii
Word Origin for crossopterygian
- Any of a mostly extinct group of lobe-finned fishes of the order Crossopterygii, whose only living member is the coelacanth. One group of crossopterygians is thought to have evolved into terrestrial vertebrates beginning in the Devonian Period. See more at coelacanth.