Struthioniformes is an order of birds with only a single extant family, Struthionidae, containing the ostriches. Several other extinct families are known, spanning across the Northern Hemisphere, from the Early Eocene to the early Pliocene, including a variety of flightless forms like the Paleotididae, Geranoididae, Eogruidae and Ergilornithidae, the latter two thought to be closely related to Struthionidae.
Palaelodus is an extinct genus of bird of the Palaelodidae family, distantly related to flamingos. They were slender birds with long, thin legs and a long neck resembling their modern relatives, but likely lived very different livestyles. They had straight, conical beaks not suited for filter feeding and legs showing some similarities to grebes. Their precise lifestyle is disputed, with researchers in the past suggesting they may have been divers, while more recent research suggests they may have used their stiff toes as paddles for swimming while feeding on insect larvae and snails. This behavior may have been key in later phoenicopteriforms developing filterfeeding bills. The genus includes between five and eight species and is found across Europe, Australia, New Zealand, Asia and possibly South America. However some argue that most of the taxa named from Europe simply represent differently sized individuals of one single species. Palaelodus was most abundant during the Late Oligocene to Middle Miocene periods, but isolated remains from Australia indicate that the genus, or at least a relative, survived until the Pleistocene.
Presbyornis is an extinct genus of anseriform bird. It contains two unequivocally accepted species; the well-known P. pervetus and the much lesser-known P. isoni. P. pervetus was approximately the size and shape of a goose, but with longer legs; P. isoni, known from a few bones, was much larger, more than swan-sized. Other fossils, more doubtfully assigned to this genus, are also known.
Strigogyps is an extinct genus of prehistoric bird from the Middle Eocene to Early Oligocene of France and Germany. It was probably around the size of a large chicken or a guan, weighing not quite 1 kilogram (2.2 lb). Apparently, as indicated by the ratio of lengths of wing to leg bones, S. sapea was flightless. Its legs were not adapted to running, so it seems to have had a walking lifestyle similar to trumpeters. Unlike other Cariamiformes, which appear to have been mostly carnivorous, Strigogyps specimens suggest a herbivorous diet.
The Pelagornithidae, commonly called pelagornithids, pseudodontorns, bony-toothed birds, false-toothed birds or pseudotooth birds, are a prehistoric family of large seabirds. Their fossil remains have been found all over the world in rocks dating between the Early Paleocene and the Pliocene-Pleistocene boundary.
Copepteryx is an extinct genus of flightless bird of the family Plotopteridae, endemic to Japan during the Oligocene living from 28.4 to 23 mya, meaning it existed for approximately 5.4 million years.
Paraphysornis is an extinct genus of giant flightless terror birds that inhabited Brazil during Late Oligocene or Early Miocene epochs. Although not the tallest phorusrhacid, Paraphysornis was a notably robust bird, having short and robust tarsal bones not suited for pursuit hunting.
Psychopsidae is a family of winged insects of the order Neuroptera. They are commonly called silky lacewings.
Eremopezus is a prehistoric bird genus, possibly a palaeognath. It is known only from the fossil remains of a single species, the huge and presumably flightless Eremopezus eocaenus. This was found in Upper Eocene Jebel Qatrani Formation deposits around the Qasr el Sagha escarpment, north of the Birket Qarun lake near Faiyum in Egypt. The rocks its fossils occur in were deposited in the Priabonian, with the oldest dating back to about 36 million years ago (Ma) and the youngest not less than about 33 Ma.
Juncitarsus is an extinct genus of wading birds from the Eocene of the United States and Germany. Though previously considered a flamingo, it is likely a stem-flamingo, possibly a relative of the group which contains both flamingos and grebes (Mirandornithes).
Bathornis is an extinct lineage of birds related to modern day seriemas, that lived in North America about 37–20 million years ago. Like the closely related and also extinct phorusrhacids, it was a flightless predator, occupying predatory niches in environments classically considered to be dominated by mammals. It was a highly diverse and successful genus, spanning a large number of species that occurred from the Priabonian Eocene to the Burdigalian Miocene epochs.
Phoenicopterus minutus is an extinct species of flamingo which inhabited California during the Late Pleistocene. It was originally discovered in San Bernardino County, California in the Lake Manix beds, where it coexisted with a second, larger flamingo species.
Phoenicopterus copei is an extinct species of flamingo that inhabited North America during the Late Pleistocene. Its fossils have been discovered in Oregon, California, Mexico and Florida. Many of these localities preserve the remains of juvenile individuals, indicating that this species nested at the lakes found there. In some areas like California and Florida it coexisted with smaller flamingo species. P. copei was a large species of Phoenicopterus, described as being greater in size than modern American flamingos.
Tonsala is an extinct genus of Plotopteridae, a family of flightless seabird similar in biology with penguins, but more closely related to modern cormorants. The genus is known from terrains dated from the Late Oligocene of the State of Washington and Japan.
Phoenicopterus stocki, also known as Stock's flamingo, is an extinct species of flamingo from the Pliocene of Chihuahua, Mexico. It was described in 1944 as a small bodied flamingo species known from assorted fragmentary remains, including bones of the tibia and the wings. The discovery of juvenile remains suggests that the locality where the fossils were found represents a shallow lagoon or mudflat that housed a breeding colony.
Phoenicopterus floridanus is an extinct species of flamingo that lived during the Pliocene in what is now Florida and potentially North Carolina.
Xenorhynchopsis is an extinct genus of flamingo from the Pliocene to Pleistocene Lake Eyre basin of Australia. Initially described as species of stork, the two known Xenorhynchopsis species are vastly different in size. X. minor is the older and small of the two species, ranging from the Pliocene to Pleistocene and being described as having reached a size smaller than that of the lesser flamingo. X. tibialis meanwhile appears to have been restricted to Pleistocene strata and was notably bigger, being counted as one of the biggest known flamingos in the fossil record.
Adelalopus is an extinct genus of palaelodid bird from the lowermost Oligocene of Belgium. It is the oldest member of its family and the largest known palaelodid from Europe, slightly larger than Megapaloelodus goliath. It contains a single species, Adelalopus hoogbutseliensis.
Olympidytes is an extinct genus of Plotopteridae, a family of large, flightless marine bird superficially similar to modern penguins but more closely related to cormorants and gannets. It lived during the Late Eocene or the Early Oligocene, in what is today the State of Washington and Japan.
Klallamornis is an extinct genus of Plotopteridae, a family of large, flightless birds related to modern cormorants, darters, gannets, and boobies. This genus included the largest North American plotopterids. Its remains can be found in Late Eocene to Late Oligocene rocks from the Makah Formation, the overlying Pysht Formation and the Lincoln Creek Formation of the State of Washington. During its existence, Klallamornis was the largest plotopterid on the North American continent. The first fossil remains attributed to the taxon were collected in 1983, although the genus wasn't described until 2016.
