Palaeocursornis
Encyclopedia
Palaeocursornis is a monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 genus of prehistoric bird
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...

. The species P. corneti, described in 1984, was initially assumed to be a flightless paleognathe
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....

, possibly a ratite
Ratite
A ratite is any of a diverse group of large, flightless birds of Gondwanan origin, most of them now extinct. Unlike other flightless birds, the ratites have no keel on their sternum—hence the name from the Latin ratis...

, but it may actually be more primitive and not even a neornithine but an ornithuromorph bird or indeed not a bird at all (Benton et al., 1997). The distal part of a left femur
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...

 (MTCO-P 1637) is the only material known to date. It was found in Early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 (Berriasian
Berriasian
In the geological timescale, the Berriasian is an age or stage of the Early or Lower Creteceous. It is the oldest or lowest subdivision in the entire Cretaceous. It spanned between 145.5 ± 4.0 Ma and 140.2 ± 3.0 Ma...

, around 143 mya) rocks in a mine at Cornet
Brusturi, Bihor
Brusturi is a commune in Bihor County, northwestern Romania with a population of 4,238 people. It is composed of eight villages: Brusturi, Cuieşd, Loranta, Orvişele, Păuleşti, Picleu, Ţigăneştii de Criş and Varasău....

 near Oradea
Oradea
Oradea is the capital city of Bihor County, in the Crișana region of north-western Romania. The city has a population of 204,477, according to the 2009 estimates. The wider Oradea metropolitan area has a total population of 245,832.-Geography:...

 in northwestern Romania
Romania
Romania is a country located at the crossroads of Central and Southeastern Europe, on the Lower Danube, within and outside the Carpathian arch, bordering on the Black Sea...

.

The animal occurred on what at that time was an archipelago
Archipelago
An archipelago , sometimes called an island group, is a chain or cluster of islands. The word archipelago is derived from the Greek ἄρχι- – arkhi- and πέλαγος – pélagos through the Italian arcipelago...

 of volcanic and coral island
Coral island
A coral island is the result of an atoll whose lagoon has dried up or been filled in with coral sand and detritus. This state is typically the last in the life cycle of an island, the first being volcanic and the second being an atoll. Most of the world's coral islands are in the Pacific Ocean...

s towards the east of the Piemont-Liguria Ocean
Piemont-Liguria Ocean
The Piemont-Liguria basin or the Piemont-Liguria Ocean was a former piece of oceanic crust that is seen as part of the Tethys Ocean...

. As the archipelago lay around 35°N latitude
Latitude
In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the Equator. The latitude is an angle, and is usually measured in degrees . The equator has a latitude of 0°, the North pole has a latitude of 90° north , and the South pole has a...

 in a warmer, wetter climate than exists today, it was roughly similar to today's Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...

 or Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

. The habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...

 of Palaeocursornis was hilly, karst
KARST
Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...

ic terrain with numerous freshwater and/or brackish rivers, lakes and swamps.(Benton et al., 1997)

Taxonomy

Initially, the bones were described as Limnornis corneti (Kessler & Jurcsák, 1984). However, that genus name had already been given to the Curve-billed Reedhaunter
Curve-billed Reedhaunter
The Curve-billed Reedhaunter is a species of bird in the Furnariidae family. It is found marshy areas of north-eastern Argentina, south-eastern Brazil, and Uruguay. It occupies a similar ecological niche to some reed warblers.The Curve-billed Reedhaunter is placed in the monotypic genus Limnornis...

 (L. curvirostris), an ovenbird
Ovenbird (family)
Ovenbirds or furnariids are a large family of small suboscine passerine birds found in Mexico, and Central and South America. They form the family Furnariidae...

. Moreover, the bones ascribed to the new taxon turned out to be from two different species, possibly not even closely related. Unfortunately, the new name to replace Limnornis corneti was referring to the material of the other species (which thus became Eurolimnornis corneti
Eurolimnornis
Eurolimnornis is the name given to a monotypic genus of fossil bird from the Early Cretaceous. E. corneti probably was a primitive, but essentially modern bird and may indeed be an early neognathe ancestral to the grebes, although the alternative theories that it was a theropod or pterosaur or a...

), creating considerable confusion since it assigned the same binomen
Binomen
In zoological nomenclature, a binomen , is the two-part name of a species. The term was introduced in 1953, abolishing the previously used "binomial name" . A binomen consists of a generic name and a specific epithet...

 (corneti) to both species. Subsequent attempts to redescribe the femur as Palaeocursornis biharicus were invalid as far as the binomen is concerned, but at least established a correct genus (Kessler & Jurcsák, 1986). The currently valid name, Palaeocursornis corneti, was first mentioned by Jurcsák & Kessler in 1985, but it was a nomen nudum
Nomen nudum
The phrase nomen nudum is a Latin term, meaning "naked name", used in taxonomy...

at that time and only became valid the following year, when the current genus was validly established (albeit with an unnecessarily synonymous species name), as mentioned above. This confusing history of synonymy was clarified by Bock & Bühler (1996):

Synonyms
  • Limnornis corneti Kessler & Jurcsák 1984
  • "Palaeocursornis corneti" Kessler & Jurcsák 1985 (nomen nudum)
  • "Palaeocursornis biharicus" Kessler & Jurcsák 1985 (nomen nudum)
  • Palaeocursornis biharicus Kessler & Jurcsák 1986
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