Talenkauen is a genus of basal iguanodont dinosaur from the Campanian or Maastrichtian age of the Late Cretaceous Cerro Fortaleza Formation, formerly known as the Pari Aike Formation of Patagonian Lake Viedma, in the Austral Basin of Santa Cruz, Argentina. It is based on MPM-10001A, a partial articulated skeleton missing the rear part of the skull, the tail, and the hands. The type and only species is Talenkauen santacrucensis. Discovery and naming One among a string of discoveries of ornithopods in South America, following taxa such as Gasparinisaura and Anabisetia, the specimen that would become Talenkauen was collected in February 2000 and would later be described and named in a short 2004 paper by Fernando E. Novas and colleagues. It was discovered on Los Hornos Hill on the coast of Viedma Lake, in the Santa Cruz Province region of Argentina. Geologically, it hails from the Cerro Fortaleza Formation. The holotype specimen is MPM–10001A, a relatively complete and articulated skeleton. The name Talenkauen is derived from the words "Talenk, meaning small, and kauen, meaning skull, both from the Aonikenk language. The specific name santacrucensis refers to the province of Argentina where it was found. Following its original, preliminary description, the taxon was described more thoroughly described in an unpublished PhD disseration in 2007 by Andrea V. Cambiaso. In 2020 an extensive description was published by Sebastián Rozadilla and colleagues. It has been recognized that, nestled amongst the rock matrix of the holotype specimen, are a collection of minuscule bone fragments and teeth. Identifiable as the teeth of some degree of ornithopod, and associated with the adult specimen, this is considered to be a neonatal, or recently hatched, baby specimen of Talenkauen. It was described in a 2013 paper, which separated the specimen number MPM–10001 into MPM–10001A, for the adult specimen, and MPM–10001B, for the neonate. The specimen is one of only very few embryonic or hatchling ornithopod specimen, and was the very first discovered from the southern hemisphere. Wear on the tiny, 1.7mm wide tooth crowns indicate the individual had fed, meaning it was not an embryo and had hatched, but only recently before death. It was noted as possible that the adult had been practicing parental care due to the individuals being found together, but that more concrete evidence would be needed to confidently make such an assertion. Description Talenkauen was rather like Dryosaurus in shape and build, but with