OKINAWAN
OPISTHOBRANCH OF THE WEEK

Plocamopherus ceylonicus (Kelaart, 1858) 20mm
Photo by Atsushi Ono

Opisthobranch of the Week Data

Taxonomy:

Frequency on Okinawa: Collection Data:
[brackets indicate range for all Okinawa-collected specimens of the species]


Species Account:

        Plocamopherus ceylonicus is considered to be very rare in Okinawan waters; I've not seen the animal here on Okinawa's main island although I've previously featured several members of the genus from Okinawan waters (included in list below). Atsushi mentions (pers. comm.) collecting two of the three individuals he has seen in the Keramas* and of course considers the species to be very rare here. I've added a second image of P. ceylonicus from the Keramas, also furnished by Atsushi. Bill Rudman has a series of photographs of T. ceylonicus posted on the Sea Slug Forum and I've added the following comments concerning the species from the Forum (Rudman, 2000) as well:

Brown patches and speckling with orange-yellow spots around the edge of the foot and on the mantle. The four papillae surrounding the gills are tipped by a large rounded pinkish knob which flashes light when disturbed. It is not known how this luminescence occurs. The posterior tip of the foot extends into a long tapering 'tail'.

        Previously I've featured several members of the genus Plocamopherus on these pages and as of the current date, there are several described and undescribed species reported from Okinawan waters. These featured animals are as follows:

  • P. ceylonicus (the above featured animal)
  • P. imperialis
  • P. maculatus
  • P. tilesii
  • P. species 1
  • P. species 2
  • P. species 3
  • Literature Cited:

            * Keramas = the Kerama Islands Group, located 30 ~ 40 kilometers west of the Okinawa capitol, Naha.


    Page Date: 04 Oct '04
    Page Modification Date: 19 Mar '12
    Digitally manipulated photo
    Copyright © 2012 Robert F. Bolland