门: 节肢动物门
纲: 易尾纲
目: 融背目
科: 未定
属: Skioldia
种: 古盾形虫
描述:
古盾形虫是一种稀有物种，最大的超过 10 厘米长。
其背甲外骨骼融合成一体，形似近椭圆形的盾牌，边缘具有许多小刺。它的特征很少，非常不显著的轴部，在背甲侧边缘几乎消失的背沟大致划分出了13个前后缘紧贴的体节。外骨骼的中部（胸部）大约有九节，其边界比假定的头部和尾部要长。前缘附近具一对眼睛，毗邻发育良好的轴向硬骨（喙板），其后被认为存在唇瓣。多分的节触角弯回向外骨骼下方，其后是每个体节下成对的双肢型附肢。
Skioldia仅存在一个种，并只保存在澄江生物群
Phylum: Arthropoda
Class: Vicissicaudata
Order: Cheloniellida
Family: uncertain
Genus: Skioldia
Specie: aldna
Description:
Skioldia aldna is a rare species, the largest of which are over 10 cm long.
The dorsal exoskeleton is fused into a single, broadly suboval‐shaped shield much of which is bordered by tiny spines. It is mostly featureless apart from a weakly defined axis and furrows that demarcate some 13 segments that meet edge‐to‐edge and are lost at the margin. The middle (thoracic) part of the exoskeleton has about nine segments, whose boundaries are longer than those on the putative head and tail regions. A pair of eyes occurs close to the anterior margin, adjacent to a well‐developed axial sclerite (rostral plate) behind which there is a putative hypostome. The multisegmented antenna curves back under the exoskeleton. It is succeeded by paired biramous appendages under each segment, as seen impressed on the dorsal surface of the exoskeleton.
Skioldia is known only from one species and the Chengjiang biota.
时代: 寒武系第二统第三阶
主要产地: 澄江生物群，中国，云南
Age: Cambrian Series 2 Stage 3
Principal localities: Chengjiang biota, Yunnan, China
Xian-Guang H., Siveter D. J., Siveter D. J., et al. The Cambrian fossils of Chengjiang, China: The flowering of early animal life[M]. John Wiley & Sons, 2017.
Legg D. A., Sutton M. D., Edgecombe G. D.. Arthropod fossil data increase congruence of morphological and molecular phylogenies[J]. Nature communications, 2013, 4(1): 1-7.