Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
Département Sciences de la Terre, Faculté des Sciences et Techniques-Guéliz, Université Cadi Ayyad, Avenue Abdelkrim el Khattabi BP 549, 40000 Marrakech, Morocco.
Sci Rep. 2017 Feb 17;7:42616. doi: 10.1038/srep42616.
Xandarellida is a well-defined clade of Lower Palaeozoic non-biomineralized artiopodans that is exclusively known from the early Cambrian (Stage 3) Chengjiang biota of South China. Here we describe a new member of this group, Xandarella mauretanica sp. nov., from the middle Cambrian (Stage 5) Tatelt Formation of Morocco, making this the first non-trilobite Cambrian euarthropod known from North Africa. X. mauretanica sp. nov. represents the youngest occurrence of Xandarellida - extending its stratigraphic range by approximately 10 million years - and expands the palaeobiogeographic distribution of the group to the high southern palaeolatitudes of West Gondwana. The new species provides insights into the lightly sclerotized ventral anatomy of Xandarellida, and offers stratigraphically older evidence for a palaeobiogeographic connection between Burgess Shale-type euarthropod communities in North Africa and South China, relative to the (Tremadocian) Fezouata biota.
Xandarellida 是一个明确的下古生代无矿化节肢动物类群，仅从华南早寒武世（阶段 3）澄江生物群中得知。在这里，我们描述了一个来自摩洛哥中寒武世（阶段 5）塔泰尔特组的该组的新成员，Xandarella mauretanica sp. nov.，这是已知的第一个来自北非的无三叶虫寒武纪真节肢动物。X. mauretanica sp. nov. 代表了 Xandarellida 的最年轻出现 - 将其地层范围延长了约 1000 万年 - 并将该组的古生物地理分布扩展到了西冈瓦纳的高南部古纬度。新物种深入了解了 Xandarellida 轻度硬化的腹侧解剖结构，并提供了有关北非和华南伯吉斯页岩型节肢动物群落之间古生物地理联系的更早的地层证据，相对于（塔伦阶）费祖阿塔生物群。
