Which annelid fossils are found most often?

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annelid *The structure of polychaetes.* (Left) Free-moving polychaetes. (A) *Neanthes,* (B) *Nereis.* (Right) Tube-dwelling (sedentary) polychaetes. (C) *Amphitrite,* (D) *Sabella.*

Because annelids possess almost no hard body parts, their fossil record is limited. The specimens encountered most frequently are the tubes constructed by polychaetes and the tough, chitinous jaws of polychaetes, which are known as scolecodonts.1