Tambja tentaculata from Guam

Dear Clay & Patty Jo,
Thanks for this photo of what is at present a rare species, known only from Apra Harbour. Perhaps the publicity will bring a few more records to light from elsewhere. I have included a close-up of the head alongside because it shows the large enrolled oral tentacles which gave this species its name. These tentacles are more characteristic of a species of Roboastra then a species of Tambja. In your photo you can also see the 'lateral slot' as a dark line midway between the rhinophores and the oral tentacles.

As I mentioned when recently discussing Tambja gratiosa [message #14519], the long Roboastra-like oral tentacles in T. tentaculata, which on all other anatomical features is a species of Tambja, may explain the similar long tentacles in T. gratiosa, which was reported by Bergh to have radular teeth characteristic of Tambja.

While preparing a Fact Sheet for this species, and adding it to the Tambja affinis colour group page, I noticed its very close similarity in colour to Tambja olivaria. I wonder if the enrolled oral tentacles can partly unroll? If so they would look very like the large flaps in the photos of  T. olivaria on the Fact Sheet for that species.

Best wishes,
Bill Rudman