The polythyridium is a component of the gut that surrounds the entrance of the intestine in priapulids of genus Tubiluchus. It comprises tuberculate and hairy plates associated with a strong muscle. These plates may help to keep unwanted particles out of the gut.[1]

References

edit
  1. ^ J. van der Land (1970). "Systematics, zoogeography, and ecology of the Priapulida". Zoologische Verhandelingen. 112 (1): 1–118. ISSN 0024-1652.