''Hunucornis huayanen'' is an extinct

grebe Grebes () are aquatic diving birds in the order (biology), order Podicipediformes (). Grebes are widely distributed freshwater birds, with some species also found in sea, marine habitats during Bird migration, migration and winter. Most grebes f ...

species from the Las Flores Formation, a

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

-aged deposit in central Argentina. It is known from two specimens containing fragmentary pieces of the left forelimb and femur. It is the oldest fossil evidence of grebes in South America.

History

The holotype INGEO-PV-376 and the referred material INGEO-PV-371 were collected, along with other fossil bird remains, from several field expeditions to Candelaria Creek over ten years, soon later to be described by Federico L. Agnolín, Gerardo Álvarez Herrera, Sebastián Rozadilla, and Victor Contreras in a 2025 article about this late Miocene avian assemblage. The authors named the material ''Hunucornis huayanen,'' which the genus means "Hunuc's bird", which comes from

Huarpe The Huarpes or Warpes are an Indigenous people of Argentina, living in the Cuyo region. Some scholars assume that in the Huarpe language, this word means "sandy ground," but according to ''Arte y Vocabulario de la lengua general del Reino de C ...

cosmogony about the first man who was friend to the animals, and the ephipet species name is Allentiac for "swim". The name refers to the fact ''H. huayanen'' is the oldest fossil evidence of grebes in South America.

Classification

The authors (Agnolín et al., 2025) did not perform a phylogenetic analysis of ''Hunucornis'' placement in Podicipedidae. Still, due to the similarities mentioned above, the genus has anatomical features shared with ''

Miobaptus ''Miobaptus'' is a fossil genus of grebe that is known from several specimens collected from Czechia and Lake Baikal dating from the Early Miocene to Middle Miocene. Considered to be one of the most primitive genera of grebes, the anatomy of ''M ...

'' of Early to Middle Miocene Eurasia. However, other aspects of the forelimb and the femur are also found in extant grebes but not in ''Miobaptus''.

Paleobiology

''Hunucornis huayanen'' comes from the Huayquerian-aged Las Flores Formation, located in the Puchuzum area of the Calingasta Valley. The locale is dated between 8 and 5 million years ago. Based on the assemblage of avian fossils that have been recovered there, there seems to have been a significant freshwater habitat that supported a diverse array of waterbirds. These included

waterfowl 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 i ...

, palaelodids,

heron Herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 75 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genus ''Botaurus'' are referred to as bi ...

s, stilts, and avocets. The anatomy of Hunucornis supports their ecology as being more or less identical to extant grebes.

References

{{Taxonbar, from=Q133809358 Podicipediformes Prehistoric bird genera Fossil taxa described in 2025