Claim: Biomphalaria straminea is part of the phylum Mollusca, the second largest phylum of invertebrate animals.
Evidence: Biomphalaria straminea is a species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails. Phylum: Mollusca Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda.