Short S-shaped chaeta, either simple-pointed or bearing two teeth on its distal end. The commonest type of chaetae in Oligochaeta; particularly, prevailing in ventral bundles of most taxa.

Cernosvitoviella atrata.
C. atrata 2 , chaetal bundle.
A. psammophilum 3 , chaetae.
H. gordioides 2 , chaetae.
P. volki 2 , chaeta.

Alternative form for sigmoid chaeta : sigmoid chaetae.