Phylum Annelida (True Worms)
Approximate Number of Species: 16,500
Largest: The hydrothermal vent tubeworm, Riftia pachyptila, reaches lengths of 7.9 feet (2.4 meters)
Smallest: Dinophilus gyrociliatus reaches lengths of only 0.002 inches (0.05 mm)
References:
Brusca RC & Brusca GJ (2003) Invertebrates (Sinauer Associates, Inc., Publishers, Sunderland, MA) 2nd Ed.
Rouse GW & Pleijel F (2001) Polychaetes (Oxford University Press, London).
Westheide W (1990) Polychaetes: interstitial families. Synopsis of the British Fauna, eds Kermack DM & Barnes RSK (Universal Book Services, Oegstgeest), pp 1-152.