Compound chaetae of A Sphaerosyllis pirifera (falciger, unidentate, almost smooth on margin) B Trypanosyllis coeliaca (falciger, bidentate with both teeth similar, moderate spines on margin) C Eusyllis assimilis (falciger, bidentate, proximal tooth longer than distal one, short spines) D Syllis garciai (spiniger-like, long spines on margin); E Syllis garciai (falciger, bidentate, both teeth similar, long spines) F Syllis krohnii (falciger, bidentate, proximal tooth shorter than distal one, short spines on margin) G Syllis amica (thick simple chaeta by blade loss and shaft enlargement) H Syllis gracilis (thick simple chaeta by blade and shaft fusion). Aciculae of: I T. coeliaca (straight, pointed) J E. assimilis (distally bent at an angle) K S. gracilis (acuminate) L Syllis prolifera (distally rounded).