Diodora aspera (Rough keyhole limpet)
2005 Mary Jo Adams
from above, the rough keyhole limpet is oval in shape with a circular
hole marking the apex, just anterior to the center. Course
ribs radiate out from the hole. It reaches a length of about
2 ¾ inches. The animal is gray or white, sometimes
with darker lines. The actual surface of the animal may however
be obscured due to the presence of encrusting algae or other organisms.
spite of its common name, the rough keyhole limpet is not a true
limpet but is more closely related to abalones. Its gills
are more primitive than those of true limpets and water circulation
through the animal is also different. In addition, unlike limpets,
which tend to be herbivores, this species prefers a carnivorous
diet, feeding more on encrusting sponges and bryozoans than on algae.
It is preyed on by several species of sea stars.
keyhole limpets carry the commensal scaleworm Arctonoe vittata
up under its shell in the mantle groove. If attacked
by a sea star, the scaleworm has been known to come to the defense
of its host by biting the sea star's tube feet.
This page was created by Mary Jo Adams on 12/5/05.