Definition of diphycercal in English:
diphycercal
adjectiveˌdɪfɪˈsəːk(ə)lˌdifəˈsərk(ə)l
Zoology (of a fish's tail) approximately symmetrical and with the vertebral column continuing to the tip, as in lampreys.
Contrasted with heterocercal, homocercal
Example sentencesExamples
- Bodies are long and slender, somewhat like salamanders, with a diphycercal tail.
- The symmetrical, diphycercal tail, not perfected by gnathostomes until the Cretaceous, was standard equipment on heterostracans in the Silurian.
- The Heterostracan head is covered with several armoured plates, the body with large scales and the tail is most often diphycercal.
- In Strepsodus the tail was diamond shaped and diphycercal; in Gooloogongia loomesi it was nearly so.
- Sharks, and similar chondrichthyes, have heterocercal tails; the diphycercal tails are found in lungfish and their relatives; and the homocercal tail is characteristic of bony fish.
Origin
Mid 19th century: from Greek diphu- 'of double form' + kerkos 'tail' + -al.