Fuxianhuiida

All currently known species are from Cambrian Series 2 aged deposits in Yunnan Province, including the Chengjiang biota.

The cephalon is covered by a head shield and contains stalked eyes connected by the anterior sclerite, antennae, a butterfly shaped hyposome and a posterior facing mouth.

Fuxianhuiids possess specialized post-antennal appendages with serrated edges used for food processing.

[1] In most Fuxianhuiids, the thorax tergites narrow posteriorly, terminating in either a swimming paddle or paired flukes with a tail spine.

In members of Fuxianhuiidae the thorax is divided into two sections, the anterior wide opisthothorax and the posterior narrow limbless tail-like abdomen.

Restoration of Alacaris , with anterior of Chengjiangocaris bottom right.