Hexinlusaurus
Encyclopedia
Hexinlusaurus is a genus
of basal
ornithischia
n dinosaur
from the Middle Jurassic
of China. The holotype
(ZDM T6001, Zigong Dinosaur
Museum, Dashanpu, People's Republic of China
), consists of an almost complete, articulated skull and some postcrania
l material, collected from a terrestrial sandstone
within the Lower Shaximiao Formation (?Bajocian
) at the famous dinosaur-bearing quarries at Dashanpu. A paratype (ZDM T6002) consists of a partial skull and postcranial remains. Previously, it had been described as a species
of Yandusaurus
, Y. multidens (He and Cai, 1983), but was reclassified as a new taxon
by Paul M. Barrett, Richard J. Butler and Fabien Knoll in 2005
, who diagnosed this anatomically conservative species as follows: "A small ornithischian dinosaur distinguished from all other basal ornithischians by a single autapomorphy, the presence of a marked concavity that extends over the lateral surface of the postorbital." The etymology
of the genus name honors Professor He Xin-Lu (Chengdu University of Technology) who originally named the specimen as Y. multidens + the Greek
sauros (=lizard
). Hexinlusaurus was a small, fleet-footed herbivore
.
Other dinosaurs known from Dashanpu include the sauropod Shunosaurus
, the theropod Gasosaurus
, and the stegosaur Huayangosaurus
.
"Proyandusaurus". This name originally appeared in an abstract attributed to Fabien Knoll, which was apparently published without his consent.http://dml.cmnh.org/2003Sep/msg00169.htmlhttp://www.paleofile.com/Demo/Mainpage/Taxalist/Dinosaurs/Ornithopoda.htm
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 basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
ornithischia
Ornithischia
Ornithischia or Predentata is an extinct order of beaked, herbivorous dinosaurs. The name ornithischia is derived from the Greek ornitheos meaning 'of a bird' and ischion meaning 'hip joint'...
n 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 the Middle Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
of China. 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...
(ZDM T6001, Zigong 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...
Museum, Dashanpu, People's Republic of 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...
), consists of an almost complete, articulated skull and some postcrania
Postcrania
Postcrania[p] in zoology and vertebrate paleontology refers to all or part of the skeleton apart from the skull. Frequently, fossil remains, e.g...
l material, collected from a terrestrial sandstone
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...
within the Lower Shaximiao Formation (?Bajocian
Bajocian
In the geologic timescale, the Bajocian is an age or stage in the Middle Jurassic. It lasted from approximately 171.6 Ma to around 167.7 Ma . The Bajocian age succeeds the Aalenian age and precedes the Bathonian age....
) at the famous dinosaur-bearing quarries at Dashanpu. A paratype (ZDM T6002) consists of a partial skull and postcranial remains. Previously, it had been described as a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of Yandusaurus
Yandusaurus
Yandusaurus is a genus of herbivorous basal euornithopod dinosaur from the Bathonian age of China.-Discovery and naming:...
, Y. multidens (He and Cai, 1983), but was reclassified as a new taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
by Paul M. Barrett, Richard J. Butler and Fabien Knoll in 2005
2005 in paleontology
-New taxa:-New taxa:-Xiphosurans:* Fossils of Lunataspis, the earliest known xiphosuran, are discovered in Canada. It was not given a formal description until 2008, however.-New taxa:-Newly named dinosaurs:...
, who diagnosed this anatomically conservative species as follows: "A small ornithischian dinosaur distinguished from all other basal ornithischians by a single autapomorphy, the presence of a marked concavity that extends over the lateral surface of the postorbital." The etymology
Etymology
Etymology is the study of the history of words, their origins, and how their form and meaning have changed over time.For languages with a long written history, etymologists make use of texts in these languages and texts about the languages to gather knowledge about how words were used during...
of the genus name honors Professor He Xin-Lu (Chengdu University of Technology) who originally named the specimen as Y. multidens + the Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
sauros (=lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
). Hexinlusaurus was a small, fleet-footed herbivore
Herbivore
Herbivores are organisms that are anatomically and physiologically adapted to eat plant-based foods. Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in...
.
Other dinosaurs known from Dashanpu include the sauropod Shunosaurus
Shunosaurus
Shunosaurus, meaning "Shu Lizard", is a genus of sauropod dinosaur from Middle Jurassic beds in Sichuan Province in China, 170 million years ago...
, the theropod Gasosaurus
Gasosaurus
Gasosaurus was a tetanuran dinosaur discovered in Dashanpu, China. The scientific name, meaning "Gas Lizard", honours the gasoline company that found the Dashanpu fossil quarry in Sichuan Province, now named as the Lower Shaximiao Formation. It had strong legs but short arms, and like most...
, and the stegosaur Huayangosaurus
Huayangosaurus
Huayangosaurus is a genus of stegosaurian dinosaur from the Middle Jurassic of China. The name derives from "Huayang", an alternate name for Sichuan , and "saurus", meaning "lizard"...
.
"Proyandusaurus"
Before being officially named Hexinlusaurus, this genus was briefly known under the informal nameNomen nudum
The phrase nomen nudum is a Latin term, meaning "naked name", used in taxonomy...
"Proyandusaurus". This name originally appeared in an abstract attributed to Fabien Knoll, which was apparently published without his consent.http://dml.cmnh.org/2003Sep/msg00169.htmlhttp://www.paleofile.com/Demo/Mainpage/Taxalist/Dinosaurs/Ornithopoda.htm
External links
- Hexinlusaurus at Thescelosaurus! (under Neornithischia)