My Temple of Nature: Gaudy Gastropods II

Monday, December 17, 2012

Gaudy Gastropods II

And now about the Opisthobranch family. This group, also marine mollusks, includes sea slugs known as headshield slugs which have a broader head than the nudibranchs, using it to burrow under the sand where they often live just beneath the surface. The 'shield' prevents the sand from entering the mantle. Some species have well developed cilia around the mouth which are used to track their prey. Some are also brightly colored like the nudibranchs (see previous post). This group includes the sacoglossa, or 'sap-sucking' sea slugs that digest the 'sap' from the algae. Some species use the chloroplasts, the organelles that conduct photosynthesis, within their own tissues so the sea slug can conduct photosynthesis for their own use, which explains their nickname as the 'solar-powered sea slug'. The opisthobranch family also includes some shelled species. Besides sea slugs, sea snails, sea hares, sea angels and sea butterflies are included in the family. Even though they are called sea hares, they are a type of sea slug with an internal soft shell, are herbivores, and their color indicates the color of seaweed that they eat. They are the largest gastropod species reaching up to 30 inches long. Sea angels are also a type of small sea slug, but the foot has developed into flapping appendages they use to 'fly' through the water and they are mostly transparent. Sea butterflies are actually sea snails, that may or may not have a shell. Their foot has also taken on wing-like properties and they swim freely or float on the currents.