Lithornithiformes
Encyclopedia
Lithornithiformes is an extinct order
of early paleognath
birds. Lithornithiform birds are known from fossils dating to the Upper Paleocene
through the Middle Eocene of North America and Europe. All are extinct today.
Lithornithids had long, slender, bills for probing. They closely resembled modern Tinamou
s. The smaller members in Genus Lithornis
and Pseudocrypturus
were good fliers, but the heavier Paracathartes
was probably only a facultative flier. The ungual
s were more curved than Tinamous and probably allowed better perching in trees.
The Order was erected by Dr. Peter Houde in 1988. Three Genera are included; Lithornis
, Paracathartes
, and Pseudocrypturus
. There are eight known species across these Genera
. Promusophaga (Harrisson
& Walker, 1977) may belong in lithornithiformes too.
Lithornithid birds possessed a rhynchokinetic skull with relatively unfused cranial bones, a weakly fused pygostyle
and a splenial
. They had a strongly developed keel on the sternum.
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
of early paleognath
Paleognathae
The Palaeognathae or paleognaths are one of the two living superorders of birds. The other living superorder is Neognathae. Together these two clades form the subclass Neornithes....
birds. Lithornithiform birds are known from fossils dating to the Upper Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...
through the Middle Eocene of North America and Europe. All are extinct today.
Lithornithids had long, slender, bills for probing. They closely resembled modern Tinamou
Tinamou
The tinamous are a family comprising 47 species of birds found in Central and South America. One of the most ancient living groups of bird, they are related to the ratites. Generally ground dwelling, they are found in a range of habitats....
s. The smaller members in Genus Lithornis
Lithornis
Lithornis is a genus of extinct paleognathous birds. Lithornis were able to fly well, but are closely related to today's tinamous and ratites ....
and Pseudocrypturus
Pseudocrypturus
Pseudocrypturus is a genus of extinct paleognathous bird. One species is known, Pseudocrypturus cercanaxius. It is a relative of such modern birds as ostriches. It lived in the early Eocene....
were good fliers, but the heavier Paracathartes
Paracathartes
Paracathartes is a genus of extinct bird from the Wasachtian horizon of lower Eocene Wyoming, USA. One species, Paracathartes howardae has been described....
was probably only a facultative flier. The ungual
Ungual
An ungual is a highly modified distal toe bone which ends in a hoof, claw, or nail. Elephants and other ungulates have ungual phalanges, as did the sauropods and horned dinosaurs. A claw is a highly modified ungual phalange.As an adjective, ungual means related to nail, as in periungual .-External...
s were more curved than Tinamous and probably allowed better perching in trees.
The Order was erected by Dr. Peter Houde in 1988. Three Genera are included; Lithornis
Lithornis
Lithornis is a genus of extinct paleognathous birds. Lithornis were able to fly well, but are closely related to today's tinamous and ratites ....
, Paracathartes
Paracathartes
Paracathartes is a genus of extinct bird from the Wasachtian horizon of lower Eocene Wyoming, USA. One species, Paracathartes howardae has been described....
, and Pseudocrypturus
Pseudocrypturus
Pseudocrypturus is a genus of extinct paleognathous bird. One species is known, Pseudocrypturus cercanaxius. It is a relative of such modern birds as ostriches. It lived in the early Eocene....
. There are eight known species across these Genera
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
. Promusophaga (Harrisson
Tom Harrisson
Major Tom Harnett Harrisson DSO OBE was a British polymath. In the course of his life he was an ornithologist, explorer, journalist, broadcaster, soldier, guerrilla, ethnologist, museum curator, archaeologist, documentarian, film-maker, conservationist, and writer...
& Walker, 1977) may belong in lithornithiformes too.
Lithornithid birds possessed a rhynchokinetic skull with relatively unfused cranial bones, a weakly fused pygostyle
Pygostyle
Pygostyle refers to a number of the final few caudal vertebrae fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these....
and a splenial
Splenial
The splenial is a small bone in the lower jaw of reptiles, amphibians and birds, usually located on the lingual side between the angular and suprangular....
. They had a strongly developed keel on the sternum.