''Paralitherizinosaurus'' 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 ...

therizinosaurid Therizinosauridae (meaning 'scythe lizards')Translated paper
is a family of derived (advanc ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

Osoushinai Formation of

Hokkaido, Japan is Japan's second largest island and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by the undersea railway Seikan Tunnel. The la ...

. The genus contains a single

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

, ''P. japonicus'', known from a partial right hand and

cervical vertebra In tetrapods, cervical vertebrae (singular: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sau ...

. ''Paralitherizinosaurus'' represents the youngest

therizinosaur Therizinosaurs (once called segnosaurs) were large herbivorous Theropoda, theropod dinosaurs whose fossils have been found across the Early Cretaceous, Early to Late Cretaceous deposits in Asia and North America. Various features of the forelimbs ...

known from

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

Discovery and naming

The ''Paralitherizinosaurus''

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 ...

specimen, NMV-52, was discovered in September 2000 in layers of the Osoushinai Formation (

Yezo Group The Yezo Group is a stratigraphic group in Hokkaido, Japan and Sakhalin, Russia which is primarily Late Cretaceous in age (Aptian to Earliest Paleocene). It is exposed as roughly north–south trending belt extending 1,500 kilometres through centr ...

) in Nakagawa, Hokkaido, Japan, which dates to the early

Campanian The Campanian is the fifth of six ages of the Late Cretaceous Epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campanian s ...

age of the late Cretaceous period. The specimen consists of a partial

and the

metacarpal In human anatomy, the metacarpal bones or metacarpus form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist, which forms the connection to the forearm. The metacarpal bones ...

I, proximal ends of

unguals An ungual (from Latin ''unguis'', i.e. ''nail'') is a highly modified distal toe bone which ends in a hoof, claw, or nail. Elephants and ungulates have ungual phalanges, as did the sauropods and horned dinosaurs. A claw is a highly modified ungual ...

I and II, and nearly complete ungual III of the right hand. Some of these remains were first described by Murakami ''et al''. in 2008 as belonging to an indeterminate genus of

maniraptoran Maniraptora is a clade of coelurosaurian dinosaurs which includes the birds and the non-avian dinosaurs that were more closely related to them than to ''Ornithomimus velox''. It contains the major subgroups Avialae, Deinonychosauria, Oviraptorosa ...

theropod, possibly with therizinosauroid affinities. In 2022, Kobayashi ''et al''. described ''Paralitherizinosaurus'' as a new genus and species of therizinosaurid making it the third therizinosaur found in Japan. This taxon represents the first named therizinosaur from Japan, with two other unnamed specimens being known. The generic name, "''Paralitherizinosaurus''", combines the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

words "paralos", meaning "tidal" and "therizo", meaning "scythe", and the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

"sauros", meaning "lizard". The specific name, "''japonicus''", refers to the taxon's discovery in Japan.

Classification

In their

phylogenetic analyses In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

, Kobayashi ''et al''. (2022) recovered ''Paralitherizinosaurus'' as a member of a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

containing ''

Therizinosaurus ''Therizinosaurus'' (; meaning 'scythe lizard') is a genus of very large therizinosaurid that lived in Asia during the Late Cretaceous period in what is now the Nemegt Formation around 70 million years ago. It contains a single species, ''Therizi ...

'', ''

Suzhousaurus ''Suzhousaurus'' (meaning "Suzhou lizard") is a genus of large therizinosauroid dinosaur from the Early Cretaceous of China. The genus is known from two specimens discovered on the Xiagou Formation and Zhonggou Formation—which are situated in ...

'', and an unnamed therizinosaurid from the

Bissekty Formation The Bissekty Formation (sometimes referred to as Bissekt) is a geologic formation and Lagerstätte which crops out in the Kyzyl Kum desert of Uzbekistan, and dates to the Late Cretaceous Period. Laid down in the mid to late Turonian, it is dated ...

Uzbekistan Uzbekistan (, ; uz, Ozbekiston, italic=yes / , ; russian: Узбекистан), officially the Republic of Uzbekistan ( uz, Ozbekiston Respublikasi, italic=yes / ; russian: Республика Узбекистан), is a doubly landlocked cou ...

. The

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...

below displays the results of their phylogenetic analyses.

References

External links

* {{Taxonbar, from=Q111821206 Therizinosaurs Late Cretaceous dinosaurs of Asia Campanian genera Fossils of Japan Cretaceous Japan Fossil taxa described in 2022