Maastrichtian birds

Vegavis is a genus of extinct bird that lived in Antarctica during the Maastrichtian stage of the Late Cretaceous. The type species is Vegavis iaai, named in 2005 based on fossils from the López de Bertodano Formation. Two additional species, Vegavis geitononesos and Vegavis notopothousa, were named in 2026 based on additional material from the same formation. Vegavis potentially represents one of the earliest known crown group birds. The definitive taxonomic position of Vegavis has been a subject of debate among paleontologists for over two decades since its initial description as a member of

Avisaurus (meaning "bird lizard") is a genus of enantiornithine avialan from the Late Cretaceous of North America.

Asteriornis ("Asteria's bird") is an extinct genus of bird from the Late Cretaceous of Belgium which is known from a single species, Asteriornis maastrichtensis. It was a small, long-legged bird that lived near the coastline and co-existed with more "primitive" types of birds such as Ichthyornis. Asteriornis is one of the oldest-known birds irrefutably belonging to the group Neornithes, which encompasses all modern birds, and is possibly closely related to birds of the extant superorder Galloanserae such as chickens and ducks. It possesses characteristics of both galliformes (chicken-like bird

Brodavis is a genus of freshwater hesperornithiform birds known from the Late Cretaceous (possibly Campanian and Maastrichtian stage) of North America and Asia. It was first described and named by Larry D. Martin, Evgeny N. Kurochkin and Tim T. Tokaryk in 2012 and assigned to a new monogeneric family, Brodavidae. Four species were described and assigned to Brodavis.

Enantiornis is a genus of Enantiornithes. The type and only currently accepted species E. leali is from the Late Cretaceous Lecho Formation at El Brete, Argentina. It was described from specimen PVL-4035, a coracoid, proximal scapula and proximal humerus found close to each other and suspected to represent the left shoulder of a single individual.

Potamornis is a prehistoric bird genus that dated back to the late Maastrichtian age of the late Cretaceous period. Its scrappy remains were found in the Lance Formation at Buck Creek, USA, and additional possible remains were found in the upper Hell Creek Formation of Montana, dated to the Danian age of the Paleogene period, though these may have been reworked. A single species was named and described in 2001: Potamornis skutchi.

Canadaga (meaning "Canadian bird") is a flightless bird genus from the Late Cretaceous. The single known species is Canadaga arctica. It lived in the shallow seas around what today is Bylot and Devon Islands in Nunavut, Canada. Its fossils were found in rocks dated to the Campanian to mid-Maastrichtian age, about 67 million years ago. It was found in the Kanguk Formation

thumb|Speculative life restoration of Janavis on a beach Janavis (from the Roman god Janus and the Latin avis for bird) is an extinct toothed bird belonging to the Ichthyornithes from the Late Cretaceous of Belgium. The genus has one named species, Janavis finalidens (from Latin finalis, meaning ending or final, and dens, for tooth) that was discovered in the 1990s, reported in 2002, and described in 2022. Recovered almost simultaneously from the same area and age as Asteriornis maastrichtensis, then the oldest known modern bird, it provides information on the evolution and divergence of basal

Soroavisaurus is an extinct genus of enantiornithine birds that lived in South America during the Late Cretaceous period, about 71–69 million years ago. The only known species, Soroavisaurus australis, was named in 1993; the generic name means "sister to Avisaurus" (another enantiornithine believed to be its relative) while the specific name means "southern". All specimens confidently assigned to this species are fossilised leg bones collected from the Lecho Formation of El Brete, a locality in the province of Salta, Argentina. Some authors have proposed that either Enantiornis or Martinavis,

Torotix is a Late Cretaceous genus of aquatic birds. They lived along the shores of the Western Interior Seaway, but it is not clear whether they were seabirds or freshwater birds, as the genus is only known from a humerus. Consequently, the genus contains only one known species, Torotix clemensi. T. clemensi is represented by a single fossil specimen, a partial humerus (upper arm bone) recovered from the Lance formation of Wyoming. Its deposits are dated to the very end of the Cretaceous period, 66 million years ago.

Limenavis is a genus of ornithuran dinosaurs from the Late Cretaceous. It lived about 70 million years ago, around the Campanian-Maastrichtian boundary. Known from several broken bones, the remains of the only known species Limenavis patagonica were found in rocks of the "lower member" of the Allen Formation at Salitral Moreno, 20 km south of General Roca, Río Negro (Argentina). It is one of the closest relatives, in the fossil record, of the modern birds.

Tytthostonyx is a genus of prehistoric seabird. Found in the much-debated Hornerstown Formation which straddles the Cretaceous–Paleogene boundary 66 million years ago, this animal was apparently closely related to the ancestor of some modern birds, such as Procellariiformes and/or "Pelecaniformes". A single species is placed herein, Tytthostonyx glauconiticus.

Polarornis is a genus of prehistoric bird, either a possible member of the Vegaviidae or Aequornithes. It contains a single species Polarornis gregorii, known from incomplete remains of one individual found on Seymour Island, Antarctica, in rocks which are dated to the Late Cretaceous (López de Bertodano Formation, about 66 Ma).

Cimolopteryx (meaning "Cretaceous wing") is a prehistoric bird genus from the Late Cretaceous Period. It is currently thought to contain only a single species, Cimolopteryx rara. The only specimen confidently attributed to C. rara was found in the Lance Formation of Wyoming, dating to the end of the Maastrichtian age, which ended about million years ago. The dubious species "Cimolopteryx" maxima has been described from both the Lance Formation and the Hell Creek Formation of Montana. The humeral end of a left coracoid from the Frenchman Formation of southern Saskatchewan has also been attribut

Neogaeornis is a controversial prehistoric genus of diving bird. The single known species, Neogaeornis wetzeli, was described from fossils found in the Campanian to Maastrichtian Quiriquina Formation of Chile. It lived about 70-67 million years ago. It remains known from the single tarsometatarsus described in 1929 by Lambrecht, and today housed in the Paläontologisches Institut und Museum in Kiel, Germany.

Martinavis is a genus of enantiornithine birds which existed in what is now southern France, North America and Salta Province, Argentina during the late Cretaceous period. It was named by Cyril A. Walker, Eric Buffetaut and Gareth J. Dyke in 2007, and the type species is Martinavis cruzyensis.

Lectavis is a genus of enantiornithine avialan. Their fossil bones have been recovered from the Late Cretaceous (Maastrichtian, c. 70.6 – 66 mya) Lecho Formation at estancia El Brete, Argentina. The genus contains a single species, Lectavis bretincola.

Ceramornis is a genus of ornithuran dinosaurs from the Late Cretaceous. It lived shortly before the Cretaceous–Paleogene extinction event in the Maastrichtian, some Its remains were found in the Lull 2 location, a Lance Formation site in Niobrara County, Wyoming. A single species is known, Ceramornis major, and even that only from a proximal piece of coracoid. This is specimen UCMP V53957, which was collected by a University of California team in 1958. thumb|left|Size (lower middle right) compared to contemporary birds, pterosaurs, and a human

Pujatopouli () is an extinct genus of neoavian birds from the Late Cretaceous (Maastrichtian stage) Lopez de Bertodano Formation of Seymour Island (Marambio Island), Antarctica. The genus contains a single species, Pujatopouli soberana, known from a partially preserved skull and several associated postcranial elements, representing one of the most complete Neornithes (crown group bird) from the Mesozoic era.