Sues Hans-Dieter, Schoch Rainer R
Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Staatliches Museum für Naturkunde Stuttgart, Stuttgart, Germany.
R Soc Open Sci. 2023 Mar 22;10(3):230083. doi: 10.1098/rsos.230083. eCollection 2023 Mar.
We report the first trilophosaurid stem-archosaur from Central Europe, gen. et sp. nov., from the Middle Triassic (Ladinian) Erfurt Formation of Baden-Württemberg (Germany). It is currently known from two jaw fragments with distinctive teeth. The labiolingually wide but mesiodistally narrow maxillary and dentary teeth each have a large labial cusp from which an occlusal ridge extends lingually to a small lingual cusp. A mesial and a distal cingulum extend between the labial and lingual cusps. The mesial and distal faces of the labial cusp each bear three prominent, lingually curved apicobasal ridges (arrises). A referred partial dentary has an edentulous, expanded symphysis similar to the mandibular 'beak' in . A review of , from the Lower Triassic (Olenekian) of southwestern Russia, supports its referral to Trilophosauridae rather than Procolophonidae. Based on this reassessment and the new material from the Middle Triassic, the temporal range of trilophosaurids now spans nearly the entire Triassic Period, from the Olenekian to the Rhaetian. Trilophosaurids present craniodental features that indicate omnivory or herbivory with limited oral food processing. They were more diverse in terms of dental structure (and presumably diet) than previously assumed.
我们报道了来自中欧的首例三棱龙类干群主龙，这是一个新属新种，产自德国巴登-符腾堡州中三叠世（拉丁期）的埃尔福特组。目前已知的标本为带有独特牙齿的两块颌骨碎片。唇舌向宽但近远中向窄的上颌齿和齿骨齿均有一个大的唇侧齿尖，从该齿尖向舌侧延伸出一条咬合嵴至一个小的舌侧齿尖。一条近中缘和一条远中缘在唇侧齿尖和舌侧齿尖之间延伸。唇侧齿尖的近中面和远中面各有三条突出的、向舌侧弯曲的顶基嵴（棱）。一件归入标本的部分齿骨有一个无齿的、扩展的联合部，类似于俄罗斯西南部下三叠统（奥伦尼克阶）的下颌“喙”。对俄罗斯西南部下三叠统（奥伦尼克阶）的重新审视支持将其归入三棱龙科而非前棱蜥科。基于这一重新评估以及来自中三叠世的新材料，三棱龙类的时间范围现在跨越了几乎整个三叠纪时期，从奥伦尼克阶到瑞替阶。三棱龙类呈现出的颅齿特征表明其为杂食性或草食性，口腔食物处理能力有限。它们在牙齿结构（以及推测的食性）方面比之前认为的更加多样。
