Sacoglossa

gastropod order

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Last updated

June 17, 2026

Quick Summary

The Sacoglossa are a division within the Opisthobranchia, a subclass of gastropods, which are commonly known as snails and slugs. This group includes sea slugs that are often classified under the suborder Nudibranchia.12

Gastropods, in general, are a diverse class of mollusks with over 65,000 species found in marine, freshwater, and land environments. The classification of gastropods has undergone significant debate, with ongoing revisions based on anatomical, neurological, and molecular data.2

Within the Opisthobranchia subclass, the Sacoglossa are characterized by having a single file of radular teeth and a closed sperm duct. Some species in this order have a bivalved shell, and many feed by consuming the juices of algae.2

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gastropod
Classification
Order Sacoglossa One file of radular teeth; sperm duct a closed tube; shell reduced to bivalved (Juliidae); many feed by sucking juices out of algae; several families with uncertain limits. Order Thecosomata Shell present; pelagic ciliary feeders; no gill; 6 families. Order Gymnosomata
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Order Sacoglossa One file of radular teeth; sperm duct a closed tube; shell reduced to bivalved (Juliidae); many feed by sucking juices out of algae; several families with uncertain limits. Order Thecosomata Shell present; pelagic ciliary feeders; no gill; 6 families. Order Gymnosomata
Read More