Select Page

Pleurobranchidae Family

Family Pleurobranchidae

The molecular sequencing of Moles et al, 2023 has shown that Pleurobranchaeidae and Pleurobranchidae are two good and distinct families, recovering them to be monophyletic, after a long and tortured history of combinations and separations.
Species of Pleurobranchidae are usually easily recognized by the plump body shape with a full and rounded dorsum. There is no external shell but an internal remnant is present.
The mantle may be smooth or evenly covered with rounded pustules. Glands in the skin secrete acidic fluid for defensive purposes. A broad oral veil lies above the mouth formed between the oral tentacles. Both the oral tentacles and rhinophores are enrolled by virtue of a longitudinal slit.
Rhinophores are carried close together on top of the head.
The plume-like gill is located on the right side between the mantle and the foot. Locomotion is by cilia on the foot assisted by mucus from an anterior pedal groove. Their diet varies among species and ranges from sponges to corals and anemones to ascidians. They feed through a protrusible oral tube.
Most often seen at night or found under rocks or coral plates during the day.
In general, to differentiate from species of the Pleurobranchaeidae family, look for:
– Closely situated rhinophores
– Mantle covering foot
– Oral veil not fused to anterior of mantle
– Notum not wrinkled