''Anachronornis'' is a genus of extinct bird from the Late Paleocene (

Thanetian The Thanetian is, in the International Commission on Stratigraphy, ICS Geologic timescale, the latest age (geology), age or uppermost stage (stratigraphy), stratigraphic stage of the Paleocene epoch (geology), Epoch or series (stratigraphy), Serie ...

) of North America. One species has been described, ''Anachronornis anhimops'', from the Willwood Formation in

Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...

. It is a basal

anseriform Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which inc ...

, relative of modern waterfowl.

Etymology

''Anachronornis'' is derived from

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

ἀναχρονισμός ("out of time") and ὄρνις ("bird"), referring to the unexpectedly late appearance of a species close to the divergence between the two major waterfowl lineages, Anhimae and Anseres. The species name ''anhimops'', from ''

Anhima The horned screamer (''Anhima cornuta'') is a species of bird that belongs to a relatively small family, the Anhimidae, which occurs in wetlands of tropical South America. There are three screamer species, the other two being the southern scream ...

'' and ὄψῐς ("face", "appearance"), refers to the appearance of the head and bill to that of the

screamer The screamers are three South American bird species placed in Family (biology), family Anhimidae. They were thought to be related to the Galliformes because of similar beak, bills, but are more closely related to the family Anatidae, i.e. ducks ...

genus ''Anhima''.

Description

''Anachronornis'' has been described as

-like in the literature, although it shared characteristics with both screamer-line and duck-line anseriforms, placing it close to the divergence between the two groups. It had a "fowl-like" bill (non-spatulate, the basal condition in Galloanserae), instead of the spatulate bill found in ducks.

Discovery

The holotype, USNM 496700, was found in

Park County, Wyoming Park County is a County (United States), county in the U.S. state of Wyoming. As of the 2020 United States census, the population was 29,624. The county seat is Cody, Wyoming, Cody. Park County is a major tourism destination. The county has ove ...

as part of the Willwood Formation, preserved in a small calcereous nodule. It consists of a mostly complete skull (only missing the pterygoids), as well as assorted postcranial material. Two other fragments were found in association with the holotype in the nodule. Labelled USNM 496701 and USNM 496702, they consist respectively of a quadrate bone and a fragmentary femur, and have not been assigned to the genus or family with certainty.

References

{{Odontoanserae Fossil taxa described in 2023 Paleogene birds of North America Paleontology in Wyoming Anseriformes Prehistoric bird genera Birds described in 2023