The Trenton Limestone of the Quebec City area contains a moderately abundant and diverse ichnofauna including numerous simple trails that formed at the sediment–water interface. A rare specimen of one of these trails demonstrates that its producer was an errant polychaete annelid, Trentonia shegiriana gen. et sp. nov. It is suggested that T. shegiriana or a morphologically similar errant polychaete annelid was responsible for the production of not only the trails described herein but also the ichnospecies Walcottia rugose. Faunal, ichnofaunal and sedimentological evidence suggests that T. shegiriana inhabited a shallow water subtidal environment with water depths in the order of 10 m or less and preferred a calcisiltite substrate. In the absence of T. shegiriana these simple trails can therefore be utilized as useful palaeoenvironmental indicators.