Definition of diphycercal 1 of a tail fin : having the upper and lower portions alike or nearly so and the vertebral column extending to the tip without any upturning in lungfish and crossopterygians this symmetry is attained by the evolution of a diphycercal tail— A. S. Romer.
What are diphycercal caudal fins?
diphycercal (English) Caudal fin shape which is primitively symmetrical and pointed; the vertebral column runs straight to the tip, dividing the caudal fin symmetrically, e.g. in chimaeras, also: an internally and externally symmetrical tail fin, e.g. in Dipnoi.
What fish have diphycercal tail?
lungfish
(D) – Diphycercal means the vertebrae extend to the tip of the tail and the tail is symmetrical and expanded (as in the bichir, lungfish, lamprey and coelacanth).
What has Heterocercal caudal fins?
A heterocercal caudal fin, often found in sharks, is one in which there are two differently sized lobes, with the vertebral column of the animal extending into the longer lobe. Most fish species have what is called a homocercal caudal fin.
What are the types of fins?
For each fish, generally, there are five main fins follows: Dorsal, Pelvic, Caudal (tail), Anal and Pectoral as shown in Fig. 1. Dorsal fins are located either on the back of the fish or its top, it helps the fish during sharp turning or stops.
What means ossified?
1 : to change into bone The cartilages ossified with age. 2 : to become hardened or conventional and opposed to change so easy for the mind to ossify and generous ideals to end in stale platitudes— John Buchan. transitive verb. 1 : to change (a material, such as cartilage) into bone ossified tendons of muscle.
What are the 3 types of caudal fins?
The main types of Caudal fins found in bony fish are:
- Indented.
- Round.
- Square.
- Forked.
- Lunate.
- Pointed.
What is Gephyrocercal tail?
Definition of gephyrocercal 1 : having the dorsal and anal fins confluent at the aborted end of the vertebral column of a fish’s tail.
Can sharks survive without fins?
The sharks are often still alive when discarded, but without their fins. Unable to swim effectively, they sink to the bottom of the ocean and die of suffocation or are eaten by other predators. Some countries have banned this practice and require the whole shark to be brought back to port before removing the fins.
What is Heterocercal fin?
Definitions of heterocercal fin. a tail fin with unequal lobes in which the vertebral column turns upward into the larger lobe as in sharks. Antonyms: homocercal fin. symmetrical tail fin extending beyond the end of the vertebral column as in most bony fishes. type of: caudal fin, tail fin.
What is the difference between Homocercal and Heterocercal tail?
A heterocercal tail(unequal lobes) is long and thin, for example shark fish. A homocercal tail (equal lobes) has an even groove for example any regular fish. A homocercal fin has equally sized and dorsal and ventral lobes but with a reduced, narrowed vertebral column that supports the fins dorsal most edge.
What does Heterocercal tail mean?
Definition of heterocercal 1 of a fish tail fin : having the upper lobe larger than the lower with the vertebral column extending into the upper lobe.
What is the meaning of diphycercal?
diph·y·cer·cal. designating, of, or having a tail fin in which the upper and lower lobes taper symmetrically to a point to which the spinal column extends. Origin of diphycercal.
What is a diphycercal tail fin?
Definition of diphycercal 1 of a tail fin : having the upper and lower portions alike or nearly so and the vertebral column extending to the tip without any upturning in lungfish and crossopterygians this symmetry is attained by the evolution of a diphycercal tail — A. S. Romer 2 : having a diphycercal tail fin
Is ctenodontia diphycercal or heterocercal?
In the Ctenodontidæ the tail is diphycercal, and no jugular plates are present in the known specimens. The tail is diphycercal in all, ending in a long point, and the body is covered with cycloid scales. The tail is heterocercal, but in some cases (Squatina) approaches the diphycercal condition.
