Laboratório de Paleobiologia, Unipampa Campus São Gabriel, São Gabriel, Rio Grande do Sul, Brazil.
Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA.
Anat Rec (Hoboken). 2024 Apr;307(4):851-889. doi: 10.1002/ar.25294. Epub 2023 Aug 17.
Proterochampsidae is a clade of non-archosaurian archosauriforms restricted to the Middle to the Late Triassic of the Ischigualasto-Villa Unión Basin of Argentina and the Santa Maria Supersequence of Brazil. A reappraisal of proterochampsid specimens from the Brazilian Dinodontosaurus Assemblage Zone (AZ) of the Pinheiros-Chiniquá Sequence (late Ladinian-early Carnian) is presented here. One of the specimens was preliminary assigned to Chanaresuchus sp., whose type species comes from the Massetognathus-Chanaresuchus AZ of the Chañares Formation of Argentina. However, our revision indicates that it differs from Chanaresuchus, being more closely related to the middle-late Carnian Rhadinosuchus gracilis. We therefore propose the new taxon, Pinheirochampsa rodriguesi, to reallocate this specimen. Additionally, we present a revision of other putative Chanaresuchus occurrences in Brazil, including the only known specimen described for the Santacruzodon AZ (Santa Cruz do Sul Sequence; early Carnian), also proposing it as a new taxon: Kuruxuchampsa dornellesi. Both new species are characterized, among other features, by transverse expansion of the anterior end of the rostrum, similar to the condition present in Rhadinosuchus, but absent in Chanaresuchus, Gualosuchus, Pseudochampsa, and non-rhadinosuchine proterochampsids. These two new species expand the growing knowledge of the non-archosaurian archosauriform diversity during the Middle-Late Triassic in South America and enhance faunal and chronological comparisons between approximately coeval geological units between Argentina and Brazil.
原鳄类是一类仅局限于阿根廷伊斯奇瓜拉斯托-维拉乌尼翁盆地的中到晚三叠世和巴西圣玛丽亚超层序的非主龙类主龙形类。本文重新评估了产自巴西皮涅鲁斯-钦尼夸序列（晚拉丁期-早卡尼期）的恐龙龙类组合带的原鳄类标本。其中一个标本最初被归入查纳雷斯鳄属（Chanaresuchus），其模式种来自阿根廷查纳雷斯组的马塞托纳加托鳄-查纳雷斯鳄组合带。然而，我们的修订表明，它与查纳雷斯鳄不同，与中晚卡尼期的雷迪诺鳄更为接近。因此，我们提出了一个新的分类单元，皮涅罗鳄（Pinheirochampsa），以重新分配这个标本。此外，我们还对巴西其他可能的查纳雷斯鳄属标本进行了修订，包括圣克鲁斯组（圣克鲁斯序列；早卡尼期）中唯一已知的标本，也将其归入一个新的分类单元：库鲁夏鳄（Kuruxuchampsa）。这两个新物种的特征包括吻部前段的横向扩张，类似于雷迪诺鳄的情况，但在查纳雷斯鳄、瓜拉鳄、伪鳄龙属和非雷迪诺鳄类原鳄类中都没有。这两个新物种增加了我们对南美的中晚三叠世非主龙类主龙形类多样性的认识，并增强了阿根廷和巴西同期地质单元之间的古生物和年代学比较。
