MEANING: Claw mixture
PERIOD: Early Cretaceous
CONTINENT: Asia
Migmanychion is a small theropod from the Early Cretaceous of China. It is known from a well-articulated left hand, which gives it its name, showing a peculiar combination of features shared with therizinosauroids and oviraptorosaurs. Migmanychion is a maniraptoran theropod, but its precise placement within the clade is unclear. It seems most closely related to Fukuivenator, which is currently thought to be a basal therizinosaur. Migmanychion was roughly 2 m in length.
Abstract from paper: A new small-bodied theropod dinosaur, Migmanychion laiyang gen. et sp. nov., is erected based on appendicular skeletal material from the Lower Cretaceous of the Pigeon Hill locality, Inner Mongolia, China. This theropod shows a peculiar combination of features in the hand, in part shared with therizinosauroids, oviraptorosaurs and with the enigmatic Fukuivenator paradoxus from Japan. Phylogenetic analysis supports the closest affinity of Migmanychion with Fukuivenator, yet alternative placements among Oviraptorosauria or among the non-avialan paravians result suboptimal descriptions of the character distribution. Although this new taxon is confidently referred to Maniraptora, this result is based uniquely on derived features of the hand: only additional material could substantiate its precise placement among the bird-like theropods. Fragmentary appendicular material from the same locality cannot be unambiguously referred to Migmanychion. One specimen, including associated partial pelvis and hindlimbs, is tentatively referred to a paravian maniraptoran.
Migmanychion is from the Cretaceous. The Cretaceous is a geological period that lasted from about 145 to 66 million years ago. It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin creta, "chalk", which is abundant in the latter half of the period.
The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct flora and fauna, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by the end of the Cretaceous, coincident with the decline and extinction of previously widespread gymnosperm groups.
The Cretaceous (along with the Mesozoic) ended with the Cretaceous–Paleogene extinction event, a large mass extinction in which many groups, including non-avian dinosaurs, pterosaurs, and large marine reptiles, died out. The end of the Cretaceous is defined by the abrupt Cretaceous–Paleogene boundary (K–Pg boundary), a geologic signature associated with the mass extinction that lies between the Mesozoic and Cenozoic Eras.
Migmanychion is a theropod. Theropods are dinosaurs that are characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally carnivorous, although a number of theropod groups evolved to become herbivores and omnivores. Theropods first appeared during the Carnian age of the Late Triassic period and included all the large terrestrial carnivores from the Early Jurassic until at least the close of the Cretaceous. In the Jurassic, birds evolved from small specialized theropods, and are today represented by about 10,500 living species.