ramshorn

gastropod family

Also known as: Planorbidae

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Last updated

June 11, 2026

Quick Summary

Ramshorns are a type of snail belonging to the family Planorbidae. These aquatic snails are known for their coiled shells, which are flat and round, resembling a ram's horn. Many species are used as aquarium scavengers due to their ability to clean algae and debris. They feed by secreting a mucous net to capture food particles from the water.12

It is important to note that "ramshorn crab" refers to a different creature, a small Australian spider crab (Noxia aries), and is not related to the gastropod family.3

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gastropod
Classification
Limpets (Ancylidae), ramshorns (Planorbidae), and pond snails (Physidae); all restricted to freshwater habitats. Superorder Stylommatophora Mantle cavity a pulmonary sac; gonopores with common opening on right side or at most narrowly separated; shell conical to vestigial, heavily to weakly calcified; eyes at tips of upper (usually) tentacles;
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Limpets (Ancylidae), ramshorns (Planorbidae), and pond snails (Physidae); all restricted to freshwater habitats. Superorder Stylommatophora Mantle cavity a pulmonary sac; gonopores with common opening on right side or at most narrowly separated; shell conical to vestigial, heavily to weakly calcified; eyes at tips of upper (usually) tentacles;
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