Shishania is a chancelloriid and not a Cambrian mollusk

• 成果类型: Article
• 署名作者: Yang, Jie; Li, Wei; Chen, Ai-lin; Du, Kun-sheng; Peng, Xiao; Wang, Yu; Zhang, Xi-guang; Smith, Martin R.
• 署名单位: Yunnan University; Yuxi Normal University; Yunnan University; Durham University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13571
• DOI: 10.1126/science.adv4635
• 发表日期: 2025-05-08
• 页码: 662-664
• 关键词: eastern yunnan; shaanxi province; guanshan biota; stage 4; morphology; fossils

摘要

The Cambrian evolutionary radiation is noted for its profusion of bizarre and unfamiliar body forms, many of which illuminate the early ancestry of major animal groups. The spine-covered fossil Shishania aculeata (Cambrian Stage 4, Yunnan, China) has been interpreted as intermediate between mollusks and their lophotrochozoan ancestors. Our new material challenges this interpretation. We propose taphonomic explanations for apparent molluscan features and instead identify prominent anatomical similarities to coeval chancelloriids from nearby strata. Our reinterpretation of Shishania as an early-diverging chancelloriid helps to consolidate a model for the early evolution of this enduringly problematic group of sponge-like metazoans.