The Keys Simnia, also known as the Mediterranean Ovulid, is a species in the class of the Gastropoda and thus belongs to the phylum of the Mollusca. Simnia spelta is still mentioned as Neosimnia spelta in many sources. Under this synonym it was first described in 1758 by Linnaeus. Neosimnia is to be seen as synonymous but does not exist in the correct taxonomy.
Description
The Keys Simnia has an elongated shell, which is mostly covered by the mantle. If this is not the case, you can see the smooth surface of the shell.
The colouration is variable and depends on the gorgonian on which the snail has settled. Depending on whether it is red, yellow or white the snail adapts the colour. In addition it usually has light or dark spots.
Quite centrally, you can see a longitudinal stripe where the mantle closes.
Simnia spelta is up to 2cm long.
Habitat and Distribution
The Keys Simnia lives on gorgonians of the genera Leptogorgia, Eunicella, Paramuricea and Lophogorgia. In the Canaries at least Leptogorgia ruberrima and Leptogorgia viminalis are inhabited. In the Mediterranean Sea it is also observed on the species Eunicella singularis, Paramuricea clavata o Leptogorgia sarmentosa.
When diving in the Canaries you can find them quite often on Red Gorgonia.
Its distribution area extends from the Bay of Biscay, along the European and African coast to Angola. Simnia spelta is also found in the Mediterranean Sea, around the Azores, Cape Verde and Madeira.
Biology
The diet of the Keys Simnia consists of the polyps of Gorgonians and Coenenchym, a living tissue type that covers the skeleton. This probably also results in their colour variations, which happens by storing the pigments of the host. When eating, they are not greedy, so the host animal does not die.
Simnia spelta has seperated sexes. Fertilization occurs internally. The eggs are then deposited on the host.
References