Telmatornis
Encyclopedia
Telmatornis is a prehistoric bird
genus
of unclear affiliations. It apparently lived in the Late Cretaceous
; its remains were found in the early Maastrichtian
(c.71-68 million years ago) Navesink Formation
of New Jersey
. A single species is included today, Telmatornis priscus. It was for some time united with other taxa of aquatic birds from around the Cretaceous-Paleocene
boundary in the form taxon
"Graculavidae", the supposed "transitional shorebirds", but this group is now known to be artificial.
Some sources erroneously claim it was allied with duck
s and geese. The reason for this is that the early anseriform
Anatalavis rex was for some time included in Telmatornis. A cladistic analysis of T. priscus supports the view that this Mesozoic
bird was a member of the Charadriiformes
, the ancient and diverse group of modern birds that includes for example gull
s, auk
s and waders.
A cladistic analysis of the forelimb skeleton (Varricchio 2002) found it highly similar to the Great Crested Grebe and unlike the Painted Buttonquail (now known to be a basal charadriiform lineage), the Black-necked Stilt (a more advanced charadriiform), or the Limpkin (a member of the Grui suborder of Gruiformes), namely in that its dorsal condyle of the humerus was not angled at 20°–30° away from long axis of the humerus. The analysis did not result in a phylogenetic pattern but rather grouped some birds with similar wing shapes together while others stood separate. It is thus unknown whether this apparent similarity to grebes represents an evolutionary relationship, or whether Telmatornis simply had a wing convergent on that of grebes and moved it like they do.
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
genus
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...
of unclear affiliations. It apparently lived in the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...
; its remains were found in the early Maastrichtian
Maastrichtian
The Maastrichtian is, in the ICS' geologic timescale, the latest age or upper stage of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned from 70.6 ± 0.6 Ma to 65.5 ± 0.3 Ma...
(c.71-68 million years ago) Navesink Formation
Navesink Formation
The Navesink Formation is a 66 to 70 mya greensand glauconitic marl and sand geological formation in New Jersey. It is known for it its Cretaceous era fossil shell beds and dinosaur bones.-Description:...
of New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
. A single species is included today, Telmatornis priscus. It was for some time united with other taxa of aquatic birds from around the Cretaceous-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...
boundary in the form taxon
Form taxon
Form classification is the classification of organisms based on their morphology, which does not necessarily reflect their biological relationships...
"Graculavidae", the supposed "transitional shorebirds", but this group is now known to be artificial.
Some sources erroneously claim it was allied with duck
Duck
Duck is the common name for a large number of species in the Anatidae family of birds, which also includes swans and geese. The ducks are divided among several subfamilies in the Anatidae family; they do not represent a monophyletic group but a form taxon, since swans and geese are not considered...
s and geese. The reason for this is that the early anseriform
Anseriformes
The order Anseriformes contains about 150 living species of birds in three extant families: the Anhimidae , Anseranatidae , and the Anatidae, which includes over 140 species of waterfowl, among them the ducks, geese, and swans.All species in the order are highly adapted for an aquatic existence at...
Anatalavis rex was for some time included in Telmatornis. A cladistic analysis of T. priscus supports the view that this Mesozoic
Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...
bird was a member of the Charadriiformes
Charadriiformes
Charadriiformes is a diverse order of small to medium-large birds. It includes about 350 species and has members in all parts of the world. Most Charadriiformes live near water and eat invertebrates or other small animals; however, some are pelagic , some occupy deserts and a few are found in thick...
, the ancient and diverse group of modern birds that includes for example gull
Gull
Gulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...
s, auk
Auk
An auk is a bird of the family Alcidae in the order Charadriiformes. Auks are superficially similar to penguins due to their black-and-white colours, their upright posture and some of their habits...
s and waders.
A cladistic analysis of the forelimb skeleton (Varricchio 2002) found it highly similar to the Great Crested Grebe and unlike the Painted Buttonquail (now known to be a basal charadriiform lineage), the Black-necked Stilt (a more advanced charadriiform), or the Limpkin (a member of the Grui suborder of Gruiformes), namely in that its dorsal condyle of the humerus was not angled at 20°–30° away from long axis of the humerus. The analysis did not result in a phylogenetic pattern but rather grouped some birds with similar wing shapes together while others stood separate. It is thus unknown whether this apparent similarity to grebes represents an evolutionary relationship, or whether Telmatornis simply had a wing convergent on that of grebes and moved it like they do.