ommatophore

mollusk anatomy

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July 1, 2026

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An ommatophore is a movable stalk that bears an eye. These structures are found in some gastropods, which are a class of mollusks. In land snails, the upper tentacles are called ommatophores, and they have eyes at their tips. Mollusks are a diverse group of invertebrates, many of which have a shell secreted by a soft mantle. While some mollusks have well-developed eyes, like those in cephalopods, others have simpler photoreceptors. The term "ommatidium" refers to a single unit that makes up a compound eye, such as those found in arthropods.123456

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gastropod
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…snails the upper tentacles, or ommatophores, are invaginable (capable of being rolled in), and the eyes are borne at the tips. In freshwater basommatophorans and most prosobranchs the eyes are located at the base of the tentacles, although in such forms as Strombus the eyes are elevated onto an accessory…
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…snails the upper tentacles, or ommatophores, are invaginable (capable of being rolled in), and the eyes are borne at the tips. In freshwater basommatophorans and most prosobranchs the eyes are located at the base of the tentacles, although in such forms as Strombus the eyes are elevated onto an accessory…
Read More