Phylum Porifera (Sponges)
Approximate Number of Species: 5,000
Largest: The cloud sponge, Aphrocallistes vasus can cover an area of 11.15 feet (3.4m) x 3.6 feet (1.1m)
Smallest: The tiny sponge, Sycon cillatum, reaches a hight of only 0.002 inches (0.05mm)
References:
Brusca RC & Brusca GJ (2003) Invertebrates (Sinauer Associates, Inc., Publishers, Sunderland, MA) 2nd Ed.
B. Austin, personal communication
Grzimek B (1974) Grzimek’s Animal Life Encylopedia (Van Nostrand Reinhold Co., New York).