Several new sauropodomorphs have been described in recent years, including the unaysaurid sauropodomorph Macrocollum itaquii (Late Triassic, Brazil). This study presents a detailed description of the craniomandibular anatomy of M. itaquii based on the holotype, a paratype and a newly referred specimen. A phylogenetic analysis using an updated dataset is performed to test a previous hypothesis regarding the affinities of this taxon and its potential influence in the phylogeny of Triassic and Early Jurassic sauropodomorphs. The taxon is supported as a member of Unaysauridae. This clade is recovered as the basal-most group within Massopoda rather than the sister group to Plateosauria. However, the position of M. itaquii (and unaysaurids) is likely to be highly labile due to specific, transitional aspects of its anatomy. The most recently discovered M. itaquii specimen, in conjunction with other newly discovered specimens, serve to elucidate the transition from slender basal sauropodomorphs to more robust derived members within this group.

近年来，已经描述了几种新的蜥脚类目，包括unaysaurid蜥脚类目Macrocollum itaquii（巴西晚三叠纪）。这项研究提供了基于整体型，副型和新近引出的标本对意大利分枝杆菌的颅下颌解剖结构的详细描述。使用更新的数据集进行了系统发育分析，以测试有关该分类单元亲和性及其对三叠纪和早侏罗世人鳄形系统发育的潜在影响的先前假设。支持该分类单元作为Unaysauridae的成员。这个进化枝是马索波达最基层的群体，而不是板脲纲的姐妹群体。但是，itaquii的位置（和un科）的解剖结构特定，过渡，因此可能非常不稳定。最新发现的M. itaquii标本与其他新发现的标本一起用于阐明该组中从细长的基底拟人变体到更坚固的衍生成员的过渡。