Reconstruction of A. erjiensis (left) and A. phrixothrix (right) from the Chengjiang biota

Allonnia is a genus of coeloscleritophoran known as complete scleritomes from the Middle Cambrian Burgess Shale. It is also a constituent of the small shelly fauna.

Its earliest occurrence in Yunnan dates to the Upper Meishucunian (~ Tommotian / Cambrian Stage 2)