门: 叶足动物门
纲: 异虫纲
目: 始有爪目
科: 贫腿虫科
属: 贫腿虫属
种: 无饰贫腿虫
描述:
这种动物是迄今为止已知的最大的寒武纪异虫类之一。标本均保存为浅棕到粉红色，除了肠道和腿部衔接处偶尔呈低突起以外，其余的在黄色围岩中呈平面。这种软躯体动物的所有标本的边缘几乎都是光滑而清晰的。只有在更高的放大倍率下，才会出现表示环形纹路的轻微的波浪状外观。身体细长，向两端逐渐变细，腹部外侧有九对附肢。一个完整的标本长125.0mm，宽4.9mm。头部比尾部窄得多，两端均向末端逐渐变细。头部的长度是宽度的2~3倍，且头部的长宽比要比尾部的相应比值易变率低。附肢都向两端轻微的拉长、略微变细。可以将其划分为叶状足间距，即以叶足附着位点各圆形区域中心之间的距离来衡量。明显可见叶状足间距长度不等，中间一节长度最大。其躯干上有非常细的环纹，大约每毫米4~5个环纹，靠近头部的环纹似乎比躯干中部的环纹多一点，躯干上缺少背板。叶状足相当长，并在末端依次变细，排在中间的那些比排在末尾的更长更结实。和身体一样，叶状足也有精细的环状结构。每个叶状足都有两个爪子，并向两端变短。躯干在两端均延伸超过腿部，身体的躯干、头部和尾部之间没有明显的边界。无饰贫腿虫以活着的或死去的伊尔东体为食。这种动物更适合攀爬而不是行走，可进一步证明这种生活方式的是其肢上出现的末端爪子。这个种仅可见于澄江生物群。
Phylum: Lobopodia
Class: Xenusia
Order: Archonychophora
Family: Paucipodiidae
Genus: Paucipodia
Specie: P.inermis
Description:
This animal is one of the largest Cambrian xenusians so far known. Specimens are preserved in a light brown to pinkish color and strongly flattened against the yellow matrix, except for the occasional relief of the sediment filled parts of the gut or the leg attachment areas. The margin of all specimens of this soft-bodied animal is virtually sleek and clear. Only at higher magnication is there a slight wavy appearance indicating an annulation. The body is elongated and tapers towards both ends, and bears nine pairs of appendages ventrolaterally. A complete specimen is 125.0mm long and up to 4.9mm wide. The head is much narrower than the tail, and both ends taper towards the termination. The head is 2±3 times longer than wide. This ratio is less variable than the corresponding ratio for the tail. The appendage-bearing part is elongate and tapers slightly towards both ends. It can be divided into lobopod inter-spacings, measured as the distance between the centres of each circular area of lobopod attachment site. It is obvious that the lobopod inter-spacings are unequal in length, being largest in the middle. The trunk carries very fine annulations, about 4~5 annulations per millimetre, and the annulations near the head seem to be a little more numerous than in the middle part of the trunk. The trunk lacks dorsal plates. The lobopods are fairly long and taper successively toward the end. Those in the middle of the row are longer and sturdier than those towards the ends. Like the body, the lobopods are finely annulated. Each lobopod carries two claws, which become shorter toward both ends of the animal. The trunk extends beyond the legs at both ends, without a distinct boundary between the trunk, head, and tail sections of the body. P. inermis may have fed on living or dead Eldonia. Further evidence for this lifestyle is the occurrence of terminal claws on the limbs of P. inermis, which suggests that it was better adapted for climbing rather than walking. This species is only known from the Chengjiang biota.
时代：寒武系第二统第三阶，始莱德利基虫-武定虫化石带
主要产地: 中国云南省澄江生物群（筇竹寺组玉案山段）
Age: Cambrian Series 2, Stage 3, Eoredlichia-Wutingaspis Zone
Principal localities: Chengjiang biota (Yu’anshan Member of Chiungchussu Formation), eastern Yunnan Province, China
Xian-guang Hou,2007.The lobopodian Paucipodia inermis from the Lower Cambrian Chengjiang fauna, Yunnan, China.Lethaia,Volume37, Issue3.