一种来自秘鲁沙漠的中新世新须鲸。

A new Miocene baleen whale from the Peruvian desert.

作者信息

Marx Felix G, Kohno Naoki

机构信息

Department of Geology and Palaeontology, National Museum of Nature and Science, Tsukuba, Japan; School of Biological Sciences, Monash University, 25 Rainforest Walk, Clayton, Victoria 3800, Australia; Geosciences, Museum Victoria, Melbourne, Australia; Directorate of Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium.

Department of Geology and Palaeontology, National Museum of Nature and Science, Tsukuba, Japan; Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan.

出版信息

R Soc Open Sci. 2016 Oct 5;3(10):160542. doi: 10.1098/rsos.160542. eCollection 2016 Oct.

The Pisco-Ica and Sacaco basins of southern Peru are renowned for their abundance of exceptionally preserved fossil cetaceans, several of which retain traces of soft tissue and occasionally even stomach contents. Previous work has mostly focused on odontocetes, with baleen whales currently being restricted to just three described taxa. Here, we report a new Late Miocene rorqual (family Balaenopteridae), gen. et sp. nov., based on two exceptionally preserved specimens from the Pisco Formation exposed at Aguada de Lomas, Sacaco Basin, southern Peru. overall closely resembles modern balaenopterids, but stands out for its unusually gracile ascending process of the maxilla, as well as a markedly twisted postglenoid process of the squamosal. The latter likely impeded lateral (omega) rotation of the mandible, in stark contrast with the highly flexible craniomandibular joint of extant lunge-feeding rorquals. Overall, expands the still meagre Miocene record of balaenopterids and reveals a previously underappreciated degree of complexity in the evolution of their iconic lunge-feeding strategy.

秘鲁南部的皮斯科-伊卡盆地和萨卡科盆地以保存异常完好的大量鲸类化石而闻名，其中一些化石还保留着软组织痕迹，甚至偶尔还有胃内容物。此前的研究主要集中在齿鲸类，须鲸目前仅有三个已描述的分类单元。在此，我们基于在秘鲁南部萨卡科盆地阿瓜达德洛马斯暴露的皮斯科组中发现的两个保存异常完好的标本，报道一种新的晚中新世须鲸（须鲸科），新属新种。总体而言，它与现代须鲸科动物非常相似，但因其上颌骨异常纤细的上升突以及鳞状骨明显扭曲的关节后突而引人注目。后者可能阻碍了下颌骨向侧面（ω形）旋转，这与现存冲刺式捕食须鲸高度灵活的颅下颌关节形成鲜明对比。总体而言，它扩展了仍然稀少的须鲸科中新世记录，并揭示了它们标志性的冲刺式捕食策略在进化过程中此前未被充分认识的复杂程度。