Table 3. Comparison of morphological characters among four noticeable species, Polydora haswelli, Polydora aura, and Polydora uncinata, in Korean waters

	Boring/Non-boring	Body color	Palps	Pigmentation (prostomium)	Interchaetigers 1–4	Pygidium	Occipital tentacle	Notochaetae on chaetiger 5	Special notochaetae
Polydora haswelli	Boring	Tan	Black bars	Black or absent	Black or absent	Absent	Absent	Present	Absent
Polydora aura	Boring	Orange to tan	Absent	Absent	Absent	Absent	Present	Absent	Tight cylindrical bundles of short needles accompanying capillaries
Polydora uncinata	Boring	Tan	Black bars	Black or absent	Black or absent	Absent	Present	Present	Recurved hook accompanying capillaries

Data from Sato-Okoshi et al. (2012).