These are almost certainly large individuals of the recently described Cyerce katiae. The larger specimens have the same loose brown network on the head and the same yellow pustules as C. katiae, but the brown network does not extend over the paddles. Possibly this coloration is lost as the animal grows. We first observed this species of Cyerce on 6 May 2007 when 50 or more specimens were found aggregating under several different chunks of dead coral at depths of 8 to 10m on a coral and rubble reef behind an island along Kwajalein Atoll's east reef. The next day we revisited the site to take additional photos and only a few specimens under one rock could be found. Only one additional specimen was seen for well over a year after that, but seven more were found on 15 September 2008 and a few additional ones since then. The things we must miss by not being in the right place at the right time. This is figured in Gosliner et al (2018) as Cyerce sp. 5.
The specimen below was found on a night dive on the north end of the same island where these had been found previously. You can see a faint trace of Cyerce katiae's brown network on the lower portions of the anterior paddles, evidence that the brown network fades in larger specimens.
Here is a cluster of them found under one small rock on 15 September 2008.
Created 4 November 2007
Updated 14 June 2025