Body large, resembling a mass of vegetal debris, with large cerata and a greatly dilated and rounded oral hood around its mouth, fringed with retentive tentacles. Rhinophores very small and lamellate, emerging from tall sheaths, into which they can be retracted. Large cerata arranged along the notal edge (up to 10 pairs), easily autotomized and regenerated. Each one is oar-like shape, with a cylindrical stem and a flattened distal blade. Surface of the body and cerata bearing tubercles and ramified appendages (gills).
somewhat translucent with a pale yellow-brown or greenish ground color. The tubercles are brown, and the branched appendages paler.
common size :
usually 10-20 cm.
This bizarre-looking nudibranch is the largest and widespread Indo-Pacific. Melibe fimbriata is clearly different from Tethys fimbria, the native representative species of the family Tethyidae in the Mediterranean which is also large, but it is whitish, with the cerata bifurcated apically with black spots.
BIOLOGY / ECOLOGY
Species of this genus prey upon crustaceans, which they trap with their oral hood. Most species are capable of swimming by moving their body from side to side. Many species gain additional nutrition from symbiotic zooxanthellae. The spawn formed a delicate colorless jelly-ribbon and contained spiralling strings of egg capsules. Each egg capsule contained up to 3 embryos. The swimming veligers hatched after 8 days at 21°C. The cerata of this species contain scattered defensive glands that secrete a characteristic hyaline slime, evident when handling the living animals.
on Milos Island the specimens were found drifting, swimming and crawling around and among Cymodocea nodosa beds, at 10-12 m in depth, in a geothermally heated area; usually found in muddy seagrass beds or on muddy bottoms 2-3 m deep.