Abstract
Macaronichnus segregatis-like traces, mostly horizontal to subhorizontal, unbranched, light mineral sand-filled burrows surrounded by heavy mineral halo, are found from modern foreshore sand of Kujukuri-hama Coast, central Japan. Although some workers have considered trace fossil M. segregatis in Quaternary sediments of Japan as locomotion traces of isopod Excirolana chiltoni, the isopod was not collected from the modern sediments in which the traces occur. On the other hand, the trace-bearing sediments contain many individuals of opheliid polychaete which is well known as a trace maker of modern M. segregatis-like traces in the North America. This suggests that the traces found in the foreshore sediments of the Kujukuri-hama Coast are also produced by the opheliids.
