Willinakaqe is an extinct 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 saurolophine hadrosaurid

Hadrosaurid

Hadrosaurids or duck-billed dinosaurs are members of the family Hadrosauridae, and include ornithopods such as Edmontosaurus and Parasaurolophus. They were common herbivores in the Upper Cretaceous Period of what are now Asia, Europe and North America. They are descendants of the Upper...

 dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 which lived during the late 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...

 (late Campanian

Campanian

The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma ...

-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...

 stage) of the Río Negro Province

Río Negro Province

Río Negro is a province of Argentina, located at the northern edge of Patagonia. Neighboring provinces are from the south clockwise Chubut, Neuquén, Mendoza, La Pampa and Buenos Aires. To the east lies the Atlantic Ocean.Its capital is Viedma...

 of southern Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

.

Willinakaqe is known from several disarticulated specimens, among them juvenile and adult individuals found at the Salitral Moreno site of the Lower Member of the Allen Formation

Allen Formation

The Allen Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous The Allen Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous The Allen Formation is a geological formation in Argentina whose strata date back to the...

. The holotype

Holotype

A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 is MPCA-Pv SM 8, a right premaxilla. A second site in the Malvinas Argentinas Partido

Malvinas Argentinas Partido

Malvinas Argentinas Partido is a partido in Buenos Aires Province, Argentina, in the Gran Buenos Aires urban area. It has an area of and a population of 321,833 ....

 has rendered additional specimens. Together the material represents the majority of the skeleton.

Willinakaqe was first named by Rubén D. Juárez Valieri, José A. Haro, Lucas E. Fiorelli and Jorge O. Calvo in 2010

2010 in paleontology

-Anomalocaridids:-Newly named crustaceans:-Newly named insects:* A new family, Cascopleciidae, is published by Poinar Jr.* A new family of ceraphronoid Hymenopters, Radiophronidae, is published by Ortega-Blanco, Rasnitsyn, and Delclòs....

 and the type species

Type species

In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 is Willinakaqe salitralensis. The generic name means "Southern duck-mimic", in the Mapuche language (willi, "south", iná, "mimic" and kaqe, "duck"). The specific name refers to the Salitral.

The largest individuals found were about 9 metres (30 ft) long. Willinakaqe had long spines on its pelvis

Pelvis

In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...

 and tail base.

Phylogeny

The decribers assigned Willinakaqe to the Saurolophidae within the Hadrosauroidea

Hadrosauroidea

Hadrosauroidea is a clade or superfamily of ornithischian dinosaurs that includes the "duck-billed" dinosaurs, or hadrosaurids, and their close relatives. Many primitive hadrosauroids, such as the sail-backed Ouranosaurus, have traditionally been included in a paraphyletic "Iguanodontidae"...

.

In 2010 cladistic analyses by Prieto-Márquez confirmed that the only two hadrosaurid taxa known from South America, Willinakaqe and Secernosaurus

Secernosaurus

Secernosaurus is a genus of herbivorous dinosaur. Secernosaurus was a hadrosaur, a "duck-billed" dinosaur which lived during the Late Cretaceous. Its fossils have been found in Argentina....

, form a clade within the Saurolophinae. Prieto-Márquez & Salinas 2010, Prieto-Márquez, 2010 and Juárez Valieri e.a. considered "Kritosaurus

Kritosaurus

Kritosaurus is an incompletely known but historically important genus of hadrosaurid dinosaur. It lived about 73 million years ago, in the Late Cretaceous of North America...

" australis to be identical to Secernosaurus.

Cladogram

Cladogram

A cladogram is a diagram used in cladistics which shows ancestral relations between organisms, to represent the evolutionary tree of life. Although traditionally such cladograms were generated largely on the basis of morphological characters, DNA and RNA sequencing data and computational...

 after Prieto-Márquez, 2010: