Sipunculids are worm-like animals with tough elastic skin that inhabit tubular burrows eroded within coral or free-living in sand or mud.  They have a highly extensible proboscis called the introvert used to capture organic matter from the water column or to graze algae from the substrate.  The anal opening is located along its side.  Positive identification is based on internal anatomy.  These are preyed upon by fishes and snails and serve as intermediate hosts to a number of internal parasites.

http://en.wikipedia.org/wiki/Sipuncula

Siphonosoma sp.

FREE-LIVING SIPUNCULID

Spoon worms inhabit U-shaped burrows in soft sediment.  They have a highly extensible proboscis to capture organic matter from the substrate.

Ochetosoma erythrogrammon sp.

RED SPOON WORM