Ontogenetic moulting behavior of the Cambrian oryctocephalid trilobite Arthricocephalites xinzhaiheensis

PeerJ

article

Yifan Wang¹  Jin Peng¹  Dezhi Wang²  Hui Zhang¹  Xiuchun Luo¹  Yunbin Shao¹  Quanyi Sun¹  Chenchen Ling¹  Qiujun Wang¹ 

[1] College of Resources and Environmental Engineering, Key Laboratory of Karst Georesources and Environment, Ministry of Education, Guizhou University, Guiyang, Guizhou Province;State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences;School of Geography and Resources, Guizhou Education University

关键词: Arthricocephalites xinzhaiheensis;    Trilobite;    Gradual transition;    Ontogenetic moulting behavior;    Cambrian;    South China;   

DOI  :  10.7717/peerj.12217

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Moulting behaviors in trilobites are a crucial strategy during development. Previous studies have demonstrated inter-and intraspecific variability of moulting behavior in trilobites. Currently, ecdysial motifs for trilobites are considered not stable even within species and fewer detailed studies dealt with moulting behaviors in a single species of trilobite during development. Here a large sample of meraspid to holaspid exuviae of Arthricocephalites xinzhaiheensis (131 specimens) from the Cambrian Balang Formation of South China has allowed description of the reasonably complete ontogenic moulting sequence. Both ontogenetic stage and body size reveal gradual transition of configuration from Somersault configuration to Henningsmoen’s configuration during development. Somersault configuration is exclusive till meraspid degree five and exists in subsequent growth stages. This suggests that opening of the facial and rostral sutures allowing the emergence forward of the post-ecdysial trilobite was prevalent in early growth stages. In later development, Henningsmoen’s configuration (showing disarticulation of the cranidium) became more dominant. This study indicates that gradual transition of ontogenetic moulting behavior occurred in oryctocephalid trilobites in the early Cambrian.

【 授权许可】

CC BY