Subgenus Sipunculus (Sipunculus) Cutler & Cutler

Remarks. Cutler and Cutler (1985) reappraised the taxonomy of Sipunculus Linnaeus, and recognized two subgenera: Sipunculus (Sipunculus) Linnaeus, and Sipunculus (Austrosiphon) Fisher. In Sipunculus (Sipunculus), the nephridiopore is anterior to the anus and the spindle muscle originates on the body wall anterior to the anus. In Sipunculus (Austrosiphon), the nephridiopore is posterior to the anus and the spindle muscle originates on the rectum. Of the 10 species of Sipunculidae known in the world, eight belong to Sipunculus (Sipunculus): S. (S.) lomonossovi Murina, S. (S.) longipapillosus Murina, S. (S.) marcusi Ditadi, S. (S.) norvegicus Danielssen, S. (S.) nudus Linnaeus, S. (S.) phalloides phalloides (Pallas), S. (S.) phalloides inclusus (Sluiter), S. (S.) polymyotus Fisher, and S. (S.) robustus Keferstein. The subgenus Sipunculus (Austrosiphon) contains only two species, S. (A.) indicus Peters, and S. (A.) mundanus Selenka & Bülow. Of these 10 species, S. (S.) robustus is new to Taiwan.