[D] Willinakaqe salitralensis [sG] [T]
Juarez-Valieri, Haro, Fiorelli & Calvo 2010
Cretaceous Late Campanian Maastrichtian
Ornithischia Ornithopoda Hadrosauridae
Allen Formation, Salitral Moreno locality, north of the Provincia de Rio Negro, Argentina
A new hadrosaurid taxon from the Late Cretaceous Allen Formation is erected, on the basis of abundant cranial and postcranial material from the Salitral Moreno locality of the Rio Negro Province, Argentina. The new taxon is here named as Willinakaqe salitralensis gen. et. sp. nov., which is characterized by having an autapamorphous premaxilla with a long and convex rostrolateral surface rostral to the narial fossa and associated postcrania developing an unique character combination, inlcuding: dorsal vertebrae with a shallow fossa upon the base of the transverse processes; sacral and proximal caudal neural spines more than three times the height of the centrum; distal region of the postacetabular process of ilium ventrally defelcted, among others.
This new hadrosaurid closely resembles Secernosaurus koerneri, the other valid hadrosaurid species from South America, based in several synapomorphies, as: angle greater than 115o between the lateral margin of the facet for scapular articulation and the glenoid in the coracoid; supra-acetabular process of the ilium asymmetrical, caudodorsal margin of ilium with a well-defined ridge continuous with the dorsal margin of the proximal region of the postacetabular process. Moreover, previous records of Lambeosaurinae from the Late Cretaceous of South America are referred to W. salitralensis, and thus, the presence of lambeosaurines in this continent is here rejected. Accordingly, Wilinakaqe salitralensis gen. et sp. nov. is currently the only hadrosaurid species reported from the Allen Formation.
MPCA-Pv SM 8, a right premaxila
MPCA-Pv SM 2, partial skeleton including: dorsal, sacral and caudal vertebrae, ossified ligaments, haemapophyses, ribs, left scapula, right ilium and ischium, femora, tibiae, fibulae, calcanea and distal tarsals, end left astragalus and foot; MPCA-Pv SM 12, left maxillae with teeth; MPCA-Pv SM 03, right lower jaw, including dentary, surangular, angular, and teeth; MPCA-Pv SM 27, left scapula; MPCA-Pv SM 29, rigt coracoid; MPCA-Pv SM 32, left sternum; MPCA-Pv SM 33, left humerus; MPCA-Pv SM 39, left ilium; MPCA-Pv SM 41, right incomplete pubis.
MPCA-Pv SM 10, left maxilla; MPCA-Pv SM 4 to 6, left end right dentaries; MPCA-Pv SM 7 and 9, isolated teeth; MPCA-Pv SM 11,13 and 14, cervical vertebrae; MPCA-Pv SM 15 to 22, dorsal vertebrae; MPCA-Pv SM 22 to 25, caudal vertebrae; MPCA-Pv SM 26, dorsal rib; MPCA-Pv SM 28, scapula, MPCA-Pv SM 30 and 31, coracoids; MPCA-Pv SM 34 to 38, humeri; MPCA-Pv SM 40, ilium; MPCA-Pv SM 42 to 44, femora; MPCA-Pv SM 45 and 46, tibiae; MPCA-Pv SM 47, fibula, MPCA-Pv SM 48 to 51, metatarsals; MPCA-Pv SM 52 to 55, phalanges and unguals; MPCA-Pv SM 01, partial single skeleton including cervical, dorsal, sacral and caudal vertebrae, dorsal ribs, left scapula and coracoid, right femur, and two pedal phalanges, one of which is an ungual.
The generic name is formed by the combination of the following words of the Mapuche language: willi meaning South, iná meaning mimic and kaque meaning duck; the name thus meaning \\\"the duck-mimic of the South\\\". - The name salitralensis refers to the Salitral Moreno locality, where the first remains were recovered.
Willinakaqe salitralensis gen. nov. et sp. nov. is diagnosed by the following combination of characters among Hadrosauroidae: premaxilla with a long and convex rostrolateral surface rostral to the narial fossa (autapomorphy); narial fossa shallow, with presence of a premaxillary foramen; caudodorsal and caudolateral precesses of the premaxilla widely divergent, premaxillary denticcles not well developed; dorsal vertebrae with a shallow fossa located on the lateral surface of the neural arch, upon the base of the transverse process (autapomorphy); eight sacral vertebrae in adults, the first with a ventral keel; high neural spines in sacral and proximal caudals, more then three times the hight of the centrum; caudal neural spines showing a progressive distal expansion; dorsal border of the proximal section of the scapula straight; distal region of teh postacetabular process of ilium ventrally defelcted (autapomorphy); femur without enclosed cranial intercondylar groove.