Deltoptychius

Deltoptychius
	Menaspis armata and Deltoptychius
Temporal occurrence
	Mississippium to Pennsylvania
	345 to 299 million years
Locations
	England; North America;
Systematics
Superclass :	Jaw mouths (Gnathostomata)
Class :	Cartilaginous fish (Chondrichthyes)
Subclass :	Holocephali
Order :	Menaspiformes
Family :	Deltoptychiidae
Genre :	Deltoptychius
Scientific name
	Deltoptychius
	Morris and Roberts , 1862

Deltoptychius is an extinct genus of cartilaginous fish from the Carboniferous . She belongs to the Holocephali and lived as a nectobenthic predator.

Taxonomy

From Deltoptychius there are two Subtaxa Deltoptychius acutus Mcoy 1855 and Deltoptychius gibberuius Davis 1883, which are classified in the family Deltoptychiidae . Carroll (1988), however, counts Deltoptychius to the Menaspidae .

features

Deltoptychius was very similar in appearance to today's sea cats (Chimaeriformes) , although he lived in the Carboniferous . It had a long, whip-like tail and large, wing-like pectoral fins with which the animal glided through the water. Thanks to his big eyes he could hunt in deep water. The solid but relatively thin tooth plates were suitable for crushing hard-shell prey such as crabs and clams .

The most important anatomical feature of Deltoptychius , which he has in common with all Holocephali , is the holostyle fusion of his palatoquadratum, the only element of the upper jaw in cartilaginous fish, with the brain skull. Frontal clasps are very reduced or absent. The animals have sexual dimorphism , whereby the males are built much smaller, more delicate and angular than the females, but have a tenaculum in front of the posterior clasper .

As with all Chimaeriformes, the lower jaw suspension is holostyle . The jaw forms an angle with the longitudinal axis of the body. The arches of the lower jaw diverge at almost 90 °. In the closed position, the front jaw comes to rest above the temporomandibular joint.

literature

Carroll, Robert L .: Vertebrate Paleontology and Evolution . WH Freeman and Company, New York 1988, ISBN 0-7167-1822-7 .
Jordan, DS: The Genera of Fishes and a Classification of Fishes . Stanford University Press, 1963, pp. 1-816 .
Sepkoski, JJ: A compendium of fossil marine animal genera . In: Bulletins of American Paleontology . tape 363 , 2002, p. 1-560 .
Woodward, AS: Catalog of the Fossil Fishes in the British Museum (Natural History) Part 1 . 1889, p. 1-613 .
Zangerl, R .: Chondrichthyes I. Paleozoic elasmobranchs . In: HP Schultze (Ed.): Handbook of Paleoichthyology . Vol. 3 Elasmobranchi. Gustav Fischer Verlag, Stuttgart 1981.

Individual evidence

^ Carroll, Robert L .: Vertebrate Paleontology and Evolution . WH Freeman and Company, New York 1988, ISBN 0-7167-1822-7 .
^ Palmer, D .: The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals . Marshall Editions, London: 1999, ISBN 1-84028-152-9 , pp. 29 .
↑ Bendix-Almgreen, SE: The anatomy of Menaspis armata and the phyletic affinities of the menaspid bradydonts . In: Lethaia . tape 4 , 1971, p. 21-49 .

[1] Carroll, Robert L .: Vertebrate Paleontology and Evolution . WH Freeman and Company, New York 1988, ISBN 0-7167-1822-7 .

[2] Palmer, D .: The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals . Marshall Editions, London: 1999, ISBN 1-84028-152-9 , pp. 29 .

[3] Bendix-Almgreen, SE: The anatomy of Menaspis armata and the phyletic affinities of the menaspid bradydonts . In: Lethaia . tape 4 , 1971, p. 21-49 .