Abstract Palaeoscolecidomorphs (Palaeoscolecida and Cricocosmiidae) are widespread early Palaeozoic worms crucial to understanding the early evolution of Ecdysozoa. They are well known from the early–middle Cambrian of the Yangtze Platform of South China, but research has disproportionately focused on the well‐known Cambrian Stage 3 Chengjiang biota of Yunnan Province. Here, palaeoscolecid specimens from the Cambrian Stage 4 Guanshan biota are described, collected from a new locality in Yunnan's Fumin county. A new species of Guanduscolex Hu et al . ( Guanduscolex hexagonus ) is described , and species of Wronascolex Ivantsov they are probably an ancestral character for palaeoscolecidomorphs, regardless of the monophyly of the group.
Shi et al. (Thu,) studied this question.