User:LittleLazyLass/List of large ornithopod ichnotaxa

This list of large ornithopod ichnotaxa is a listing of ichnotaxa - taxa based on ichnites, or fossilized footprints - pertaining to dinosaurs of the group Ornithopoda.

Large ornithopod tracks have been studied since their first discovery in 1846, around the time the earliest vertebrate ichnology began to be studied. For a long time, these were simply referred to as "Iguanodon footprints", and others later as "hadrosaur footprints". Eventually, ichnogenera were coined for some of this tracks, beginning with Charles M. Sternberg's ichnogenera Amblydactylus and Gypsichnites in 1932. Over time, over fourty large ornithopod ichnospecies were coined, and many of these received little attention beyond their initial descriptions. Various studies proposed that the vast majority of these were invalid, leaving only a handful of valid taxa, and comprehensive reviews were eventually published on the issue.

Historical background
https://books.google.ca/books?hl=en&lr=&id=rCDYCQAAQBAJ&oi=fnd&pg=PA61&dq=Tetrapod+ichnofacies+of+the+Cretaceous+Hunt+2006&ots=c-YkxeWLI0&sig=uNs0ZKa2a9xPL_6Pb_oynfLu-IE&redir_esc=y#v=onepage&q=Tetrapod%20ichnofacies%20of%20the%20Cretaceous%20Hunt%202006&f=false

https://books.google.ca/books?hl=en&lr=&id=fugoCgAAQBAJ&oi=fnd&pg=PA357&dq=Hadrosaur+footprints+from+the+Upper+Cretaceous+Fruitland+Formation,+San+Juan+Basin,+New+Mexico,+and+the+ichnotaxonomy+of+large+ornithopod+footprints+Lucas+2011&ots=KZgcChxeQs&sig=GWqvpXE-RAdaUTZduD-Ja_GitrI&redir_esc=y#v=onepage&q=Hadrosaur%20footprints%20from%20the%20Upper%20Cretaceous%20Fruitland%20Formation%2C%20San%20Juan%20Basin%2C%20New%20Mexico%2C%20and%20the%20ichnotaxonomy%20of%20large%20ornithopod%20footprints%20Lucas%202011&f=false

Akmechetosauropus
Akmechetosauropus makhkamovi was described in 1993 based on a poorly preserved track from the Babtpag II site of the Luchak Formation, 6 km northwest of Akmechel, Tadjikistan, dating to the Albian. Due to its imprecise diagnosis and the quality of the associated figure, Díaz-Martínez et al. considered it to be a nomen dubium. They found the original description paper to be the only one to mention it.

Batagosauropus
Babatagosauropus bulini was described in 1993 based on a poorly preserved track from the Babtpag I site of the Luchak Formation, 45 km southwest of Hissar, Babatag Ridge, Tadjikistan, dating to the Albian. Due to its poor diagnosis and the quality of the associated figure, Díaz-Martínez et al. considered it to be a nomen dubium. They found the original description paper to be the only one to mention it.

Bonaparteichnium
Bonaparteichnium tali was named by Jorge O. Calvo in a 1991 paper alongside the other ornithopod ichnogenera Sousaichnium and Limayichnus; it hails from the Candeleros Formation of Neuquén Province, Argentina. The name of the genus honours Argentinian palaeontology José Bonaparte for his contributions to palaeontology in Argentina. The taxon was named for a 60cm footprint of a bipedal ornithopod; the heel of the track is 28cm long, making it 45% of the track. This length, above that expect for an ornithopod foot, along with the width and robustness of the heel, was the distinguishing trait cited in naming the specimen as a new ichnospecies, and is the basis of the species name tali, referring to word "talon" which means heel. In a 1999 paper Calvo would revise his opinion and consider his three ichnogenera to be synonyms. He noted the extreme similarity of the front half of the foot between Bonaparteichnium and Limayichnus, and that the length and size of a heel in a track is dependent on the method of walking; a bipedal animal walking abnormally low to the ground would produce a track such as that used to name Bonaparteichnium even in lack of a large heel as a genuine anatomical feature. He referred to B. tali as a nomen vanum. Díaz-Martínez and colleagues considered it a nomen dubium as opposed to referring the specimen to Limayichnus, as they also considered that taxon dubious. They noted that Bonaparteichnium can also be considered a taphotaxon, a term proposed by Spencer G. Lucas to refer to invalid taxa who were thought distinct due to taphonomic distortions.