January 20, 2004
From: Bill Rudman
The prominent yellow spots on Jun Imamoto's photos of Siphopteron pohnpei reminded me of the yellow spots on some examples of Siphopteron sp. 5 in Nils Anthes' message from Lizard Island. Although we know nothing of the internal anatomy of Siphopteron sp. 5, it, like S. pohnpei, lacks a flagellum on the visceral hump. Interestingly, Terry Gosliner (1989) reports on a population of animals from Kaneohe Bay, Oahu, Hawaii which he identified as Siphopteron pohnpei, which showed the same colour variation from red to brown with white and yellow spots, as reported by Nils Anthes from Siphopteron sp. 5. Gosliner also reports that the different colour forms in Hawaii mate with each other.
I will wait for comments from others familiar with living Siphopteron pohnpei, but it would seem to me that Siphopteron sp. 5 is most probably S. pohnpei, which would mean its distribution extends far into the southern Pacific.
• Gosliner,T.M. (1989): Revision of the Gastropteridae (Opisthobranchia: Cephalaspidea) with descriptions of a new genus and six new species. The Veliger, 32(4): 333-381.