''Skybalonyx'' 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 ...

drepanosaur Drepanosaurs (members of the clade Drepanosauromorpha) are a group of extinct reptiles that lived between the Carnian and Rhaetian stages of the late Triassic Period, approximately between 230 and 210 million years ago. The various species of dre ...

from the

Chinle Formation The Chinle Formation is an Upper Triassic continental geological formation of fluvial, lacustrine, and palustrine to eolian deposits spread across the U.S. states of Nevada, Utah, northern Arizona, western New Mexico, and western Colorado. In Ne ...

in the

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch ...

. The type and only known species is ''Skybalonyx skapter'', meaning "digging dung claw" from

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

. ''Skybalonyx'' is only known from numerous specimens of the enlarged claw on its second finger, characteristic of other derived drepanosaurids. However, ''Skybalonyx'' is unique compared to other drepanosaurs because its enlarged claw is wider than it is tall, and it is not as deep compared to those of the contemporary ''

Drepanosaurus ''Drepanosaurus'' (; "sickle lizard") is a genus of arboreal (tree-dwelling) reptile that lived during the Triassic Period. It is a member of the Drepanosauridae, a group of diapsid reptiles known for their prehensile tails. ''Drepanosaurus'' wa ...

'' or ''

Ancistronychus ''Ancistronychus'' is an extinct genus of drepanosaur from the Late Triassic Petrified Forest National Park in the Chinle Formation of Arizona. The type and only known species is ''Ancistronychus paradoxus'', from Ancient Greek to mean "unexpec ...

''. Functional analyses of its claws compared to other drepanosaurs and various living animals indicates that ''Skybalonyx'' (as well as ''Ancistronychus'') used its large claw for digging underground, perhaps even for burrowing. This contrasts with the inferred lifestyle of other drepanosaurids (including ''Drepanosaurus''), which were arboreal. Reports published in October 2020 indicate its remains were discovered by graduate students in 2018 and 2019 at the

Petrified Forest National Park Petrified Forest National Park is an American national park in Navajo County, Arizona, Navajo and Apache County, Arizona, Apache counties in northeastern Arizona. Named for its large deposits of petrified wood, the park covers about , encompassin ...

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

References

Drepanosaurs Late Triassic reptiles of North America Fossil taxa described in 2020 Prehistoric reptile genera {{Triassic-reptile-stub