Zoological Institute of the Russian Academy of Sciences, Universitetskaya nab. 1, 199034, Saint Petersburg, Russia.
Section Paleontology, Institute of Geosciences, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 8, 53115, Bonn, Germany.
Naturwissenschaften. 2023 Aug 2;110(4):40. doi: 10.1007/s00114-023-01868-3.
Eutriconodonta are an important group of early crown mammals with a wide distribution in the Jurassic-Cretaceous of the Northern Hemisphere and few occurrences in the Southern Hemisphere. Three taxa of eutriconodontans are known from the Early Cretaceous high-latitude Teete vertebrate assemblage in Yakutia, Russia: Sangarotherium aquilonium (Eutriconodonta incertae sedis), Gobiconodon sp. A (large), and Gobiconodon sp. B (small) (Gobiconodontidae). These three taxa are based on four specimens and indicate a remarkable taxonomic diversity of eutriconodontans at this locality. The coexistence of two Gobiconodon species, large and small, is characteristic for several Early Cretaceous vertebrate assemblages in Asia. Gobiconodon sp. A from the Teete locality is the largest species of this genus known from Asia, but is smaller than the North American G. ostromi. The spreading of Gobiconodon from Asia to North America likely occurred during the Aptian-Albian faunal dispersal event. The discovery of Gobiconodon in the Teete locality is further evidence for a dispersal route via Beringia from Asia to North America which previously has been postulated based on the occurrence of Asian dinosaur taxa in western North America at this time. The questionable record of Gobiconodon from Europe and its lack from eastern North America make a dispersal from Asia to North America via Europe less probable.
真三尖齿兽类是一类分布广泛的早白垩世-晚白垩世北半球的重要的原始有胎盘类哺乳动物,在南半球鲜有发现。俄罗斯雅库特的早白垩世高纬度 Teete 脊椎动物组合中,已知有三种真三尖齿兽类:北极兽(分类位置不定)、Gobiconodon sp. A(大型)和 Gobiconodon sp. B(小型)(真三尖齿兽科)。这三个分类单元基于四个标本,表明该地点的真三尖齿兽类具有显著的分类多样性。两种 Gobiconodon 物种,大型和小型的共存是亚洲几个早白垩世脊椎动物组合的特征。来自 Teete 地点的 Gobiconodon sp. A 是亚洲已知的该属最大的物种,但比北美的 G. ostromi 小。Gobiconodon 从亚洲传播到北美的情况很可能发生在早白垩世-晚白垩世的生物扩散事件期间。Gobiconodon 在 Teete 地点的发现进一步证明了通过白令海峡从亚洲到北美的扩散途径,此前基于此时亚洲恐龙类群在北美西部的存在提出了这种途径。欧洲有 Gobiconodon 的可疑记录,但在北美东部却没有,这使得通过欧洲从亚洲到北美的扩散不太可能。