SP-520 PEANUT WORM, Themiste (=Dendrostomum) alutacea
A small fat peanut worm that bores into rocks and coral. Under a dissecting scope it’s fascinating to watch this dwarf unsegmented worm withdrawing its introvert and then thrusting it out like the finger of a rubber glove. They can live for months in a covered finger bowl. Size: 0.5-1.0 cm.