Comodactylus
Encyclopedia
Comodactylus is a genus
of "rhamphorhynchoid" pterosaur
from the Kimmeridgian
-Tithonian
-age Upper Jurassic Morrison Formation
of Wyoming
, USA, named for a single wing metacarpal.
In 1879 collector William Harlow Reed sent some fossil material he had dug up at Como Bluff
in Quarry N° 9, or the "Mammal Quarry", to his employer Professor Othniel Charles Marsh
at New Haven
. Among it was the bone of a pterosaur, that was subsequently filed, stored and forgotten.
However, in 1981 Peter Galton
named, based on this bone, the genus Comodactylus. The type species
is Comodactylus ostromi. The genus name is derived from Como Bluff and Greek daktylos, "finger", referring to the wing finger typical of pterosaurs. The specific name honours John Ostrom
.
The holotype
is YPM 9150, consisting of an intact fourth metacarpal, 57.5 millimetres long. The metacarpal is quite robust with especially the proximal end, that touching the wrist bones, being very expanded. Such proportions are typical for basal pterosaurs, so Comodactylus was not a member of the, advanced, Pterodactyloidea
. To what other pterosaur group it did belong has, however, proven difficult to determine, due to a lack of information. The metacarpal is the only known part of the animal. Kevin Padian
in 1989 considered it a nomen dubium
. David Unwin in 1993 suggested an affinity with Nesodactylus
.
The wingspan has been estimated at 2.5 metres, exceptionally large for a pterosaur not belonging to the Pterodactyloidea. Comodactylus was also the first pterosaur outside of that group, that was found in America.
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 "rhamphorhynchoid" 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...
from the Kimmeridgian
Kimmeridgian
In the geologic timescale, the Kimmeridgian is an age or stage in the Late or Upper Jurassic epoch or series. It spans the time between 155.7 ± 4 Ma and 150.8 ± 4 Ma . The Kimmeridgian follows the Oxfordian and precedes the Tithonian....
-Tithonian
Tithonian
In the geologic timescale the Tithonian is the latest age of the Late Jurassic epoch or the uppermost stage of the Upper Jurassic series. It spans the time between 150.8 ± 4 Ma and 145.5 ± 4 Ma...
-age Upper Jurassic Morrison Formation
Morrison Formation
The Morrison Formation is a distinctive sequence of Late Jurassic sedimentary rock that is found in the western United States, which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltstone and limestone and is light grey, greenish...
of Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...
, USA, named for a single wing metacarpal.
In 1879 collector William Harlow Reed sent some fossil material he had dug up at Como Bluff
Como Bluff
Como Bluff is a long ridge extending east-west, located between the towns of Rock River and Medicine Bow, Wyoming. The ridge is an anticline, formed as a result of compressional geological folding. Three geological formations, the Sundance, the Morrison, and the Cloverly Formations, containing...
in Quarry N° 9, or the "Mammal Quarry", to his employer Professor Othniel Charles Marsh
Othniel Charles Marsh
Othniel Charles Marsh was an American paleontologist. Marsh was one of the preeminent scientists in the field; the discovery or description of dozens of news species and theories on the origins of birds are among his legacies.Born into a modest family, Marsh was able to afford higher education...
at New Haven
New Haven, Connecticut
New Haven is the second-largest city in Connecticut and the sixth-largest in New England. According to the 2010 Census, New Haven's population increased by 5.0% between 2000 and 2010, a rate higher than that of the State of Connecticut, and higher than that of the state's five largest cities, and...
. Among it was the bone of a pterosaur, that was subsequently filed, stored and forgotten.
However, in 1981 Peter Galton
Peter Galton
Peter M. Galton is a British vertebrate paleontologist working in America, who has to date written or co-written about a hundred papers in scientific journals or chapters in paleontology textbooks, especially on ornithischian and prosauropod dinosaurs.With Robert Bakker in a joint article...
named, based on this bone, the genus Comodactylus. The type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
is Comodactylus ostromi. The genus name is derived from Como Bluff and Greek daktylos, "finger", referring to the wing finger typical of pterosaurs. The specific name honours John Ostrom
John Ostrom
John H. Ostrom was an American paleontologist who revolutionized modern understanding of dinosaurs in the 1960s, when he demonstrated that dinosaurs are more like big non-flying birds than they are like lizards , an idea first proposed by Thomas Henry Huxley in the 1860s, but which had garnered...
.
The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
is YPM 9150, consisting of an intact fourth metacarpal, 57.5 millimetres long. The metacarpal is quite robust with especially the proximal end, that touching the wrist bones, being very expanded. Such proportions are typical for basal pterosaurs, so Comodactylus was not a member of the, advanced, Pterodactyloidea
Pterodactyloidea
Pterodactyloidea forms one of the two suborders of pterosaurs , and contains the most derived members of this group of flying reptiles...
. To what other pterosaur group it did belong has, however, proven difficult to determine, due to a lack of information. The metacarpal is the only known part of the animal. Kevin Padian
Kevin Padian
Kevin Padian is a Professor of Integrative Biology at the University of California, Berkeley, Curator of Paleontology, University of California Museum of Paleontology and President of the National Center for Science Education. Padian's area of interest is in vertebrate evolution, especially the...
in 1989 considered it a nomen dubium
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...
. David Unwin in 1993 suggested an affinity with Nesodactylus
Nesodactylus
Nesodactylus was a genus of "rhamphorhynchoid" pterosaur from the Oxfordian-age Upper Jurassic Jagua Formation of Pinar del Río, western Cuba....
.
The wingspan has been estimated at 2.5 metres, exceptionally large for a pterosaur not belonging to the Pterodactyloidea. Comodactylus was also the first pterosaur outside of that group, that was found in America.