Phylum Chaetognatha (Arrow Worms)
Approximate Number of Species: 1oo
Largest: Pseudosagitta gazellae at a length of 4.33 inches (110 mm)
Smallest: Spadella boucheri at a length of 0.43 inches (11 mm)
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References:
Brusca RC & Brusca GJ (2003) Invertebrates (Sinauer Associates, Inc., Publishers, Sunderland, MA) 2nd Ed.
E. Thuesen, personal communication
Casanova JP & Perez Y (2000) A dwarf Spadella (Chaetognatha) from Bora Bay (Miyako Island, Japan). Cahiers de Biologie Marine 41:137-141.