A stem-group cnidarian described from the mid-Cambrian of China and its significance for cnidarian evolution

作者：Park, Tae-yoon; Woo, Jusun; Lee, Dong-Jin; Lee, Dong-Chan; Lee, Seung-bae; Han, Zuozhen; Chough, Sung Kwun; Choi, Duck K.^*

来源：Nature Communications, 2011, 2(1): 442.

DOI：10.1038/ncomms1457

• PHYLOGENY
• NUCLEAR
• GENOME
• CORAL

Palaeontological data of extinct groups often sheds light on the evolutionary sequences leading to extant groups, but has failed to resolve the basal metazoan phylogeny including the origin of the Cnidaria. Here we report the occurrence of a stem-group cnidarian, Cambroctoconus orientalis gen. et sp. nov., from the mid-Cambrian of China, which is a colonial organism with calcareous octagonal conical cup-shaped skeletons. It bears cnidarian features including longitudinal septa arranged in octoradial symmetry and colonial occurrence, but lacks a jellylike mesenchyme. Such morphological characteristics suggest that the colonial occurrence with polyps of octoradial symmetry is the plesiomorphic condition of the Cnidaria and appeared earlier than the jelly-like mesenchyme during the course of evolution.

• 出版日期2011-8
• 单位山东科技大学; 中国极地研究中心