A New Helmetiid Arthropod from the Cambrian Chengjiang Biota

The Helmetiids is a group of weakly sclerotized Cambrian arthropods that have aroused interest on account of their trilobite affinities. Because of edge-to-edge tergite articulations and the supposed shared derived character of dorsoventral mismatch, they are considered closely related with trilobites as their possible sister taxon. The first species to be described was Helmetia expansa Walcott, 1918 from the middle Cambrian Burgess Shale Biota, but details of the ventral morphology of this species are still poorly known. Among exceptionally well-preserved arthropods from the Chengjiang Biota, Helmetiids are represented with five species: Kuamaia lata Hou, 1987; Kuamaia muricata Hou and Bergstr？m, 1997; Rhombicalvaria acanthi Hou, 1987; Saperion glumaceum Hou, Ramsk？ld and Bergstr？m, 1991, and Skioldia aldna Hou and Bergstr？m, 1997. Together these six species comprise a substantial proportion of the taxon Helmetiida.

Recently, Dr. ZHAO Fangchen from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences and his colleagues described a new helmetiid arthropod, Haifengella corona n. gen. n. sp., from the Chengjiang Lagerst？tte in Journal of Paleontology. The discovery provides new materials for the evolution and species diversity of helmetiids.

This research was supported by Chinese Academy of Sciences, National Basic Research Program of China and the National Natural Science Foundation of China.

Related information of this paper: Zhao Fangchen, Hu Shixue, Zeng Han, Zhu Maoyan. 2014. A new helmetiid arthropod from the early Cambrian Chengjiang Lagerst？tte, Southwest China. Journal of Paleontology, 88(2): 367-370.