''Majiashanosaurus'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

pachypleurosaur left, 220px, '' Pachypleurosaurus'' Pachypleurosauria is an extinct clade of primitive sauropterygian reptiles that vaguely resembled aquatic lizards, and were limited to the Triassic period. They were elongate animals, ranging in size from , w ...

or alternatively a basal

eosauropterygia Sauropterygia (" lizard flippers") is an extinct taxon of diverse, aquatic reptiles that developed from terrestrial ancestors soon after the end-Permian extinction and flourished during the Triassic before all except for the Plesiosauria bec ...

n known from the

Early Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a un ...

( Olenekian age) of Anhui Province, eastern

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

. It contains a single species, ''Majiashanosaurus discocoracoidis''.

Discovery

''Majiashanosaurus'' is known solely from the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

AGM-AGB5954, a nearly complete and articulated postcranial

skeleton A skeleton is the structural frame that supports the body of an animal. There are several types of skeletons, including the exoskeleton, which is the stable outer shell of an organism, the endoskeleton, which forms the support structure inside ...

missing, apart from the

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...

, some neck vertebrae and a small portion of the tail. This long skeleton is exposed in ventral view, i.e. from below, and preserves the last three neck vertebrae together with 19 back, three

sacral Sacral may refer to: *Sacred, associated with divinity and considered worthy of spiritual respect or devotion *Of the sacrum The sacrum (plural: ''sacra'' or ''sacrums''), in human anatomy, is a large, triangular bone at the base of the spi ...

, and more than 18

tail vertebrae The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column is the defining characteristic of a vertebrate in which the notochord (a flexible rod of uniform composition) found in all chordate ...

, as well as pectoral and pelvic girdles, most of the forelimbs and hindlimbs, and ribs. AGM-AGB5954 was collected at Majiashan, Chaohu of Anhui Province, from the Upper Member of the Nanlinghu Formation, dating to the late Olenekian stage (Spathian) of the late

, about 248

million years ago The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 teraseconds. Usage Myr (million years) is in common use in fields such as Earth science and cosmology. Myr is also used with Mya (million years ago). ...

. The ichthyopterygian ''

Chaohusaurus ''Chaohusaurus'' is an extinct genus of basal ichthyopterygian, depending on definition possibly ichthyosaur, from the Early Triassic of Chaohu and Yuanan, China. Discovery The type species ''Chaohusaurus geishanensis'' was named and des ...

'' was found co-occurring with ''Majiashanosaurus'' in the same locality.

Etymology

''Majiashanosaurus'' was first described and named by Da-Yong Jiang, Ryosuke Motani, Andrea Tintori, Olivier Rieppel, Guan-Bao Chen, Jian-Dong Huang, Rong Zhang, Zuo-Yu Sun and Cheng Ji in

2014 File:2014 Events Collage.png, From top left, clockwise: Stocking up supplies and personal protective equipment (PPE) for the Western African Ebola virus epidemic; Citizens examining the ruins after the Chibok schoolgirls kidnapping; Bundles of wat ...

and the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

is ''Majiashanosaurus discocoracoidis''. The generic name is derived from ''Majiashan'', in reference to the locality where the holotype was found, and from Greek ''saurus'', meaning "lizard", a common suffix for genus names of extinct reptile. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

is derived from Greek δίσκος, ''diskos'' meaning "disk", plus coracoid (from ''corax'', meaning "raven/crow"), in reference to its plate-like round coracoid that lacks a narrowing - such a trait is unique among

ns, but resembles the condition seen in placodonts.

References

Fossil taxa described in 2014 Pachypleurosaurs Triassic sauropterygians Early Triassic reptiles of Asia Paleontology in Anhui Sauropterygian genera {{triassic-reptile-stub