This pretty little species of the family Gastropteridae is known in the Marshalls from several specimens, and an animal that looks pretty much the same has also been recorded from Okinawa as Sagaminopteron sp. 1. The first Marshall Islands specimen was found on 25 May 2008 at a depth of 9m on Halimeda algae on the lagoon slope of the east reef of Kwajalein Atoll. It measured 12mm when crawling. We have seen these figured as Sagaminopterum nigropunctatum, but do not think they are the same as some others we figure as that species, which to us look more like the original description in Carlson & Hoff (1973).
The second specimen, shown below, was found on 29 June 2008 on a Dysidea sponge in a Halimeda patch on a Kwajalein Atoll lagoon reef at a depth of about 9m. This one was a bit smaller than the first, measuring 7mm. Two more specimens were found in similar Halimeda patches in August of 2008.
A fourth specimen, found in the same general area on 25 August 2008, measured 13mm in length and is shown below.
A pair was found in a Kwajalein reef quarry by Christina Sylvester on 11 November 2016. Note the second, smaller individual on the left side in the photo immediately below.
Created 23 June 2008
Updated 22 July 2020