Ctenochasma
Encyclopedia
Ctenochasma is a genus
of Late Jurassic pterosaur
belonging to the suborder pterodactyloidea
. Three species are currently recognized: C. roemeri (named after Friedrich Adolph Roemer
), C. taqueti, and C. elegans (formerly Pterodactylus elegans). Their fossilized remains have been found in the Solnhofen Limestone
of Bavaria
(Germany
) and eastern France
.
lifestyle, straining water through the teeth in order to capture and eat small invertebrates. The snout curved slightly upward and was rounded at the tip, and the teeth were restricted to the front half of the jaws.
The smallest species, Ctenochasma elegans, had a wingspan of only about 25 cm. Ctenochasma is distinguished by its mouth which contained as many as 260 Adult Ctenochasma had a bony crest along the skull, though this is not found in juveniles.
Comparisons between the scleral ring
s of both Ctenochasma elegans and Ctenochasma taqueti and modern birds and reptiles suggest that these taxa may have been nocturnal, and may have had activity patterns similar to modern nocturnal seabirds. This may also indicate niche partitioning with contemporary pterosaurs inferred to be diurnal, such as Pterodactylus
and Scaphognathus
.
in 1852, based on a single lower jaw full of closely packed teeth which he gave the species name Ctenochasma roemeri. A second species, C. gracile, was named by Oppel in 1862 based on a fragmentary skull. However, a year earlier, another, more complete specimen probably belonging to the same species was described and named Pterodactylus elegans by Wagner. Because the species name elegans was named before gracile, the species is now known as Ctenochasma elegans. An additional species, C. porocristata, was named by Paul de Buisonjé in 1981. However, it was differentiated mainly by the presence of a crest along the snout, which has since been shown to be a feature related to growth or sex, rather than species.
A fourth species of Ctenochasma was first described (but not named) by Philippe Taquet
in 1972. A single specimen, consisting of a partial skull with complete brain case, was found in France and housed in the collections of the Saint-Dizier Museum. Detailed comparison to other Ctenochasma specimens in 2004 confirmed that it was a new species. In honor of Taquet's work on the specimen, Christopher Bennett named the species C. taqueti in 2007.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of Late Jurassic pterosaur
Pterosaur
Pterosaurs were flying reptiles of the clade or order Pterosauria. They existed from the late Triassic to the end of the Cretaceous Period . Pterosaurs are the earliest vertebrates known to have evolved powered flight...
belonging to the suborder pterodactyloidea
Pterodactyloidea
Pterodactyloidea forms one of the two suborders of pterosaurs , and contains the most derived members of this group of flying reptiles...
. Three species are currently recognized: C. roemeri (named after Friedrich Adolph Roemer
Friedrich Adolph Roemer
Friedrich Adolph Roemer , German geologist, was born at Hildesheim, in the Kingdom of Westphalia.His father was a lawyer and councillor of the high court of justice. In 1845 he became professor of mineralogy and geology at Clausthal, and in 1862 director of the School of Mines...
), C. taqueti, and C. elegans (formerly Pterodactylus elegans). Their fossilized remains have been found in the Solnhofen Limestone
Solnhofen limestone
The Solnhofen Plattenkalk is a Jurassic Konservat-Lagerstätte that preserves a rare assemblage of fossilized organisms, including highly detailed imprints of soft bodied organisms such as sea jellies...
of Bavaria
Bavaria
Bavaria, formally the Free State of Bavaria is a state of Germany, located in the southeast of Germany. With an area of , it is the largest state by area, forming almost 20% of the total land area of Germany...
(Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
) and eastern France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
.
Description
Ctenochasma is distinguished mainly by its numerous (over 400 in adults) long, thin, curved and closely packed teeth, which lined its elongated and narrow snout. The teeth were so closely packed that they formed a comb, and in adults they projected outward away from the jaws, forming a basket, which was probably used in a filter feedingFilter feeder
Filter feeders are animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feeding are clams, krill, sponges, baleen whales, and many fish and some sharks. Some birds,...
lifestyle, straining water through the teeth in order to capture and eat small invertebrates. The snout curved slightly upward and was rounded at the tip, and the teeth were restricted to the front half of the jaws.
The smallest species, Ctenochasma elegans, had a wingspan of only about 25 cm. Ctenochasma is distinguished by its mouth which contained as many as 260 Adult Ctenochasma had a bony crest along the skull, though this is not found in juveniles.
Comparisons between the scleral ring
Sclerotic ring
Sclerotic rings are rings of bone found in the eyes of several groups of vertebrate animals, except for mammals and crocodilians. They can be made up of single bones or small bones together. They are believed to have a role in supporting the eye, especially in animals whose eyes are not spherical,...
s of both Ctenochasma elegans and Ctenochasma taqueti and modern birds and reptiles suggest that these taxa may have been nocturnal, and may have had activity patterns similar to modern nocturnal seabirds. This may also indicate niche partitioning with contemporary pterosaurs inferred to be diurnal, such as Pterodactylus
Pterodactylus
Pterodactylus is a genus of pterosaurs, whose members are popularly known as pterodactyls. It was the first to be named and identified as a flying reptile...
and Scaphognathus
Scaphognathus
Scaphognathus was a pterosaur that lived around Germany during the Late Jurassic. It had a wingspan of about one meter.-Naming:The first known Scaphognathus specimen was described in 1831 by August Goldfuss who mistook the tailless specimen for a new Pterodactylus species: P. crassirostris. The...
.
Species
The name Ctenochasma was coined by the German paleontologist Christian Erich Hermann von MeyerChristian Erich Hermann von Meyer
Christian Erich Hermann von Meyer was a German palaeontologist.He was born at Frankfurt am Main.In 1832 von Meyer issued a work entitled Palaeologica, and in course of time he published a series of memoirs on various fossil organic remains: molluscs, crustaceans, fishes and higher vertebrata,...
in 1852, based on a single lower jaw full of closely packed teeth which he gave the species name Ctenochasma roemeri. A second species, C. gracile, was named by Oppel in 1862 based on a fragmentary skull. However, a year earlier, another, more complete specimen probably belonging to the same species was described and named Pterodactylus elegans by Wagner. Because the species name elegans was named before gracile, the species is now known as Ctenochasma elegans. An additional species, C. porocristata, was named by Paul de Buisonjé in 1981. However, it was differentiated mainly by the presence of a crest along the snout, which has since been shown to be a feature related to growth or sex, rather than species.
A fourth species of Ctenochasma was first described (but not named) by Philippe Taquet
Philippe Taquet
Philippe Taquet is a French paleontologist who specializes in dinosaur systematics of finds primarily in northern Africa.He is a member of the French Academy of Sciences since November 30, 2004...
in 1972. A single specimen, consisting of a partial skull with complete brain case, was found in France and housed in the collections of the Saint-Dizier Museum. Detailed comparison to other Ctenochasma specimens in 2004 confirmed that it was a new species. In honor of Taquet's work on the specimen, Christopher Bennett named the species C. taqueti in 2007.