Opisthobranch of the Week Data
This small haminoeid, Atys sp. 1, is one which was photographed but not collected from a sandy bottom off of Ama Beach in Zamami Island, within the Kerama Islands Group, which are located 30 ~ 40 kilometers west of the Okinawa capitol, Naha. This featured animal was photographed by Atsushi Ono during December of 2008 in twelve meters of water. Atsushi's photographs are used here with his kind permission. It should be noted that Atsushi considers the species to be very rare in the Kerama Islands ... he has seen only the above featured animal (pers. comm.). I've added a second image, showing the shell of the above animal.
The following information is taken from Rudman (1998) on the Sea Slug Forum:
Atys is a herbivorous genus of shelled opisthobranchs related to Haminoea and Phanerophthalmus. It is possible when more of the many tropical species are studied that they will be placed in other genera. At present most species are tropical and have heavy well-calcified shells. In most cases the true foot is short and the shell extends a considerable distance beyond its posterior end. The parapodial flaps, which are part of the foot, therefore only fold around the anterior end of the shell. The posterior flap of tissue which looks like part of the foot, is in fact an outgrowth from the mantle cavity. A similar "false posterior foot" is found in species of Haminoea.