This would appear to be a species of Flabellina . It has tall, smooth rhinophores, about as long as the anterior tentacles, but also pointed foot corners. We had never seen this previously, but three specimens along with two of another species (Cratena sp. e640) came up in a small sample of hydroid we brought up from about 60m on the seaward slope. The hydroid is common and I had examined colonies in place several times before, but had never seen anything on it. There may be a lot of these if three could come off one small sample, but despite the colors they may be hard to see. The largest of the three, the one figured below, measured 12mm. The smallest, behind a hydroid stalk in the second photo, was about 9mm. The third specimen was in poor condition with tiny cerata and mostly black material inside the body, probably deteriorating even before found. Unfortunately, these photos are all rather low resolution. One of these photos is printed in Gosliner et al (2018) as Tenellia sp. 53, but the foot corners would seem to preclude it being in that genus.
Created 13 October 2011
Updated 5 March 2022