Characteristics Of Gastropoda (Snails, Sea Slugs and Sea Hares)

Festive Nudibranch / aa7ae, Flickr
Festive Nudibranch or Diamondback Nudibranch (Tritonia Festiva). aa7ae, Flickr

Do you know what the marine biology term " Gastropoda" means? The class Gastropoda includes snails, slugs, limpets and sea hares. These are all animals referred to as 'gastropods.' Gastropods are mollusks, and an extremely diverse group that includes over 40,000 species. Envision a sea shell, and you're thinking about a gastropod although this class contains many shell-less animals as well. This article explains the many Gastropoda characteristics.


Gastropoda Characteristics


Here's what most of them have in common:

  • Many gastropods have one shell in which the animal can withdraw. The shell is usually coiled and may be 'left-handed' or sinistral (spiraled counter-clockwise) or 'right-handed' or dextral (clockwise).
  • Gastropods move using a muscular foot.
  • All young (larval stage) gastropods undergo a process called torsion, in which the entire top of their body twists 180 degrees on their foot. This results in the placement of the gills and anus above the head. Gastropods have adapted in a variety of ways to avoid polluting their breathing water with their own wastes.
  • Due to torsion, adult gastropods are asymmetrical in form.

Scientific Classification of Gastropods

  • Kingdom: Animalia
  • Phylum: Mollusca
  • Class: Gastropoda

Feeding and Living

This diverse group of organisms employ a wide range of feeding mechanisms. Some are herbivores, and some are carnivores. Most feed using a radula.

The whelk, a type of gastropod, use their radula to drill a hole into the shell of other organisms for food. Food is digested in the stomach. Because of the torsion process described earlier, the food enters the stomach through the posterior (back) end, and wastes leave through the anterior (front) end.



Once eggs hatch, the gastropod is usually a planktonic larvae called a veliger, which may feed on plankton or not feed at all. Eventually, the veliger undergoes metamorphosis and forms a juvenile gastropod.

Habitat and Distribution

Gastropods live just about everywhere on Earth -- in salt water, fresh water and on land. In the ocean, they live in both shallow, intertidal areas and the deep sea.

Many gastropods are used by humans for food, decoration (e.g., sea shells) and jewelry.