节头虫属Arthricocephalus的概念和异名问题得到了新的厘定和更正：过去所认为的“Arthricocephalus”属中的绝大部分种应归入小掘头虫属Oryctocarella，而似节头虫属Arthricocephalites则是Arthricocephalus的晚出异名。根据采自湖南湘西花垣县子腊村一些Arthricocephalus处于不同个体发育时期的化石标本，研究并对比前人的材料后发现，诸如胸节数不同等区别很可能是由于处于个体发育不同阶段所致，而非属种间的差异，因此提出目前节头虫属的各个种整理归并至乔氏节头虫Arthricocephalus chauveaui Bergeron 1899一种中，进而根据节头虫属与其它掘头虫类三叶虫形态和地层上的比较，讨论其演化关系。%Recently, the concept and synonyms of the genus Arthricocephalus have been redefined, most species of the traditional“Arthricocephalus”should be assigned into Oryctocarella, and the Arthricocephalites is the junior synonym of Arthricocephalus. Based on several specimens of different ontogenetic development stages collected from Zila Village, Huayuan County of northwestern Hunan, this study shows that the different thoracic segments may be accounted for different development stages, but not the interspecific variations. Furthermore, several species have been reassigned into Arthricocephalus chauveaui Bergeron 1899, and the intraspecific vitiations within the genus have been discussed. The morphology and stratigraphical information of Arthricocephalus with other oryctocephlid trilobties have been compared and their evolutionary relationships have also been discussed in the current study.
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