The general muscular architecture in Tubiluchus troglodytes (Priapulida). Meiofauna Marina

We describe here the general muscular architecture of Tubiluchus troglodytes (Priapulida) based on phalloidin staining, confocal laser scanning and transmission electron microscopy. The body wall musculature is composed of a grid of circular and longitudinal muscle bundles, in the introvert, there is additional outer longitudinal musculature. T. troglodytes has pharynx protractors, wheras the introvert retractors could not be sufficiently resolved in this investigation. The muscular pharynx is followed by an organ with solid circular musculature, the polythyridium. The body wall musculature proceeds into the long tail. In the posterior region, anus and urogenital pores are surrounded by circular musculature.