Before revision: Invertebrate group Phylum Image Estimated number ofdescribed species Insects Arthropoda 180px 1,000,000 Arachnids Arthropoda 180px 102,248 Snails Mollusca 180px 85,000 Crustaceans Arthropoda 180px 47,000 Clams Mollusca 180px 20,000 Corals Cnidaria 180px 2,175 Octopuses/Squid Mollusca 180px 900 Velvet worms Onychophora 180px 165 Nautilus Mollusca 180px 6 Horseshoe crabs Arthropoda 180px 4 Othersjellyfish, echinoderms,sponges, other worms etc.
After revision: Paul Ryan thumbInvertebrate group Phylum Image Estimated number ofdescribed species Insects Arthropoda 180px 1,000,000 Arachnids Arthropoda 180px 102,248 Snails Mollusca 180px 85,000 Crustaceans Arthropoda 180px 47,000 Clams Mollusca 180px 20,000 Corals Cnidaria 180px 2,175 Octopuses/Squid Mollusca 180px 900 Velvet worms Onychophora 180px 165 Nautilus Mollusca 180px 6 Horseshoe crabs Arthropoda 180px 4 Othersjellyfish, echinoderms,sponges, other worms etc.