When I first posted images of this dorid to social media, I got numerous responses: “Oh, it looks like a dessert. . . . “a birthday cake with two candles on it” . . . “a bunny rabbit” . . . “I just want to pet his stomach or head or whatever that big white area is.” Yes, this teeny (this one was 20 mm max) Cockerell’s Dorid is beyond cute, and finding it had my heart leaping for at least 24 hours — that is, until I came across the Golden Dirona the very next day in the same area. Apparently these little ones use their strong raspers to feed on the orangish-brown bryzoan Hincksina velata — there was plenty of that in the low intertidal zone where s/he was found — see photos below.
If you happen to find one of these beauties with a line of orange bumps down the centre of its mantle, you have found an entirely different species. Check out the Monterey Bay Aquarium site for more information on the difference between the Limacia cockerelli and the Limacia macdonaldi. If you happen to see a MUCH larger version of a nudibranch with similar colouring, you have likely come across the Sea Clown Triopha.