Abstract:
Eight fossil tetrapod footprints from lake-shore deposits in the Lower Jurassic Moenave Formation at the St. George Dinosaur Discovery Site (SGDS) in southwestern Utah cannot be assigned to the prevalent dinosaurian (Anomoepus, Eubrontes, Gigandipus, Grallator, Kayentapus) or crocodyliform (Batrachopus) ichnotaxa at the site. The tridactyl and tetradactyl footprints are incomplete, consisting of digit- and digit-tip-only imprints. Seven of the eight are likely pes prints; the remaining specimen is a possible manus print. The pes prints have digit imprint morphologies and similar anterior projections and divarication angles to those of Brasilichnium, an ichnotaxon found primarily in eolian paleoenvironments attributed to eucynodont synapsids. Although their incompleteness prevents clear referral to Brasilichnium, the SGDS tracks nevertheless suggest a eucynodont track maker and thus represent a rare, Early Mesozoic occurrence of such tracks outside of an eolian paleoenvironment.
摘要:
犹他州西南部圣乔治恐龙发现地点(SGDS)的下侏罗纪Moenave地层湖岸沉积物中的八个化石四足动物足迹无法分配给流行的恐龙(Anomoepus,Eubrontes,Gigandipus,施莱托,Kayentapus)或该地点的鳄鱼形(Batrachopus)ichnotaxa。三指和四指足迹不完整,由数字和数字尖端的印记组成。八个中的七个可能是pes指纹;其余的标本可能是Manus指纹。pes印刷品具有数字印记形态,并且与the的前投影和分叉角相似,一种主要存在于风尘古环境中的冰球,归因于新球藻突触。尽管它们的不完整性阻止了明确的转诊,尽管如此,SGDS曲目仍建议使用eucynodont曲目制造商,因此代表了一种罕见的曲目,在风成古环境之外,这种轨迹的早期中生代发生。