门: 未定
纲: 未定
目: 未定
科: 未定
属：云南虫属
种: 铅色云南虫
描述:
身体前部有七对弓型结构，边缘发育丝状结构。上下两个棒状结构，每个结构上具一条线性结构。在弓型丝状架构与腹侧连接处发育一个小的，圆形结构。囊状结构位于弓型丝状架构外部，在每个囊之间有一个开口。身体后部背侧为重复的近矩形结构组成。该结构的最后单元有一个小的后凸，最前端的单元为三角形轮廓。腹侧是一系列重复的轴向条纹。大约在身体的中部区域，腹侧边缘具四对的圆形结构。螺旋状肠道位于身体的腹侧，从中部延伸至末端。
Phylum: uncertain
Class: uncertain
Order: uncertain
Family: uncertain
Genus：Yunnanozoon Hou, Ramsköld & Bergström, 1991
Specie: Yunnanozoon lividum Hou, Ramsköld & Bergström, 1991
Description:
Seven paired filamentous arches in the anterior part of the body; each rod exhibiting at least one linear structure. A ventral rod small circular structures are present in the filamentous arches. Sac‐like structures lie exterior to the arches, with openings to the exterior between them. The dominant feature of the posterior part of the body, termed the dorsal repetitive units, is an elongate, semi‐circular structure made up of subrectangular subunits. The posterior‐most subunit of this structure bears a small posterior projection; the anterior‐most subunit has a distinctive triangular morphology. Ventral to the dorsal repetitive units is an anteroposteriorly oriented axial zone exhibiting transverse stripes. At approximately mid‐length, close to the ventral margin, a series of four, paired circular structures occurs. The ventral side of the body, from midlength posteriorly, also bears a ventral tube that in some specimens appears coiled.
时代：寒武纪，第二统，第三阶
主要产地: 中国云南澄江生物群。
Age: Cambrian, Series 2, Stage 3
Principal localities: The Chengjiang Lagerstaätte, Yunnan Province, China.
Shu, D.G., Zhang, X.L., and Chen, L. 1996. Reinterpretation of Yunnnaozoon as the earliest known hemichordate. Nature, 380, 428-430.
Cong, P.Y. et al. 2015. New data on the palaeobiology of the enigmatic Yunnanozoans from the Chengjiang biota, lower Cambrian, China. Palaeontology, 58:1, 45-70.