Microdontosaurus
Encyclopedia
"Microdontosaurus" is the name given to an as yet undescribed
genus
of sauropod dinosaur
from China
. It was named from fossils from the Middle Jurassic
-age Dapuka Group
of Xinjiang
, and assigned to the Homalosaurpoidea, an outdated classification of diplodocids and titanosaur
s. The intended type species
is "M. dayensis." Due to its obscurity, at least two other identifications of "Microdontosaurus" can be found on the Internet. One identification, as given by The Dinosaur Encyclopaedia, claims the name refers to a sauropod from the Late Cretaceous
. The other identification, as given in this Dinosaur Mailing List post, is that the name is for a melanorosaurid prosauropod. As with other informal names created by Zhao in 1985 or 1983, it has not been used since then, and may have been redescribed under another name.
Nomen nudum
The phrase nomen nudum is a Latin term, meaning "naked name", used in taxonomy...
genus
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 sauropod dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
from China
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...
. It was named from fossils from the Middle Jurassic
Middle Jurassic
The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....
-age Dapuka Group
Dapuka Group
The Dapuka Group is a geological formation in Asia. It dates back to the Middle Jurassic.-Vertebrate fauna:...
of Xinjiang
Xinjiang
Xinjiang is an autonomous region of the People's Republic of China. It is the largest Chinese administrative division and spans over 1.6 million km2...
, and assigned to the Homalosaurpoidea, an outdated classification of diplodocids and titanosaur
Titanosaur
Titanosaurs were a diverse group of sauropod dinosaurs, which included Saltasaurus and Isisaurus. It includes some of the heaviest creatures ever to walk the earth, such as Argentinosaurus and Paralititan — which some believe have weighed up to 100 tonnes...
s. The intended 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 "M. dayensis." Due to its obscurity, at least two other identifications of "Microdontosaurus" can be found on the Internet. One identification, as given by The Dinosaur Encyclopaedia, claims the name refers to a sauropod from the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...
. The other identification, as given in this Dinosaur Mailing List post, is that the name is for a melanorosaurid prosauropod. As with other informal names created by Zhao in 1985 or 1983, it has not been used since then, and may have been redescribed under another name.