Díaz-Martínez Ignacio, Pereda-Suberbiola Xabier, Pérez-Lorente Félix, Canudo José Ignacio
CONICET-Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro, General Roca 1242, 8332 Fisque Menuco (General Roca), Río Negro, Argentina; Facultad de Ciencas, Estudios Agroalimentarios e Informática, Universidad de La Rioja, Madre de Dios 51-53, 26006 Logroño, La Rioja, Spain.
Universidad del País Vasco/Euskal Herriko Unibertsitatea, Facultad de Ciencia y Tecnología, Departamento de Estratigrafía y Paleontología, Apartado 644, 48080, Bilbao, Spain.
PLoS One. 2015 Feb 12;10(2):e0115477. doi: 10.1371/journal.pone.0115477. eCollection 2015.
Large ornithopod tracks are known from the Upper Jurassic to the uppermost Cretaceous rocks of all continents but Antarctica. They include the tracks historically called Iguanodon footprints, iguanodontid footprints, hadrosaur/hadrosaurid footprints, and other large ornithopod tracks that have been used to define ichnotaxa. More than 40 ichnospecies based on large ornithopod tracks have been defined, but the validity of many of them is questionable.
METHODOLOGY/PRINCIPAL FINDINGS: 34 ichnogenera and 44 ichnospecies have been analysed in this work. Many of them are considered to be invalid because they have been defined on the basis of poorly preserved tracks without diagnostic features, have an inadequate diagnosis, or are based on temporal and/or geographical criteria. Only eight ichnospecies belonging to the ichnogenera Caririchnium, Iguanodontipus and Hadrosauropodus are here regarded as valid.
CONCLUSIONS/SIGNIFICANCE: The monospecific ichnogenus Iguanodontipus (I. burreyi) is characterized by a small, rounded heel and elongate, narrow digit impressions. Its distribution is limited to the Berriasian-Valanginian of Europe. Caririchnium consists of four ichnospecies (C. magnificum [type ichnospecies], C. kortmeyeri, C. billsarjeanti and C. lotus) with a large, rounded heel and short, wide digit impressions. This ichnogenus ranges from the Berriasian-Hauterivian to the Aptian-Albian of South America, North America, Asia and Europe. Finally, Hadrosauropodus (three ichnospecies: H. langstoni [type ichnospecies], H. leonardii and H. kyoungsookimi) shows a large, bilobed heel and short, wide digit impressions. It is known from the Aptian-Albian to the Maastrichtian of North America, Asia and Europe. The ichnofamily Iguanodontipodidae includes large iguanodontian tracks characterized mainly by mesaxonic, tridactyl and subsymmetrical pes tracks that are as wide as (or wider than) long and have one pad impression in each digit and one in the heel. Its distribution is confidently limited to the Cretaceous of Europe, Asia, North America and South America.
除南极洲外，在各大洲的上侏罗统至上白垩统岩石中均发现了大型鸟脚类足迹。它们包括历史上被称为禽龙足迹、禽龙科足迹、鸭嘴龙/鸭嘴龙科足迹以及其他用于定义遗迹分类单元的大型鸟脚类足迹。基于大型鸟脚类足迹已定义了40多个遗迹种，但其中许多的有效性值得怀疑。
方法/主要发现：本研究分析了34个遗迹属和44个遗迹种。其中许多被认为是无效的，因为它们是基于保存不佳且无诊断特征的足迹定义的，诊断不充分，或者是基于时间和/或地理标准。在此，仅属于Caririchnium、禽龙足迹属（Iguanodontipus）和鸭嘴龙足迹属（Hadrosauropodus）的8个遗迹种被视为有效。
结论/意义：单种遗迹属禽龙足迹属（I. burreyi）的特征是足跟小而圆，趾痕细长且窄。其分布仅限于欧洲的贝里亚阶-瓦朗吉阶。Caririchnium由4个遗迹种组成（C. magnificum [模式遗迹种]、C. kortmeyeri、C. billsarjeanti和C. lotus），足跟大而圆，趾痕短而宽。该遗迹属分布于南美洲、北美洲、亚洲和欧洲的贝里亚阶-豪特里维阶至阿普特阶-阿尔比阶。最后，鸭嘴龙足迹属（3个遗迹种：H. langstoni [模式遗迹种]、H. leonardii和H. kyoungsookimi）显示足跟大且呈双叶状，趾痕短而宽。在北美洲、亚洲和欧洲的阿普特阶-阿尔比阶至马斯特里赫特阶均有发现。禽龙足迹科遗迹包括大型禽龙类足迹，其主要特征是中轴型、三趾且近对称的足印，长宽相等（或宽于长），每个趾有一个肉垫印，足跟有一个肉垫印。其分布确切地限于欧洲、亚洲、北美洲和南美洲的白垩纪。
