Nudibranchs of Hawaii, Main Page
Why this nudibranch has the common name of “gloomy” is beyond me. Its colour, shape and form are anything but. The black/green background is highlighted with deep china-blue spots, and gills that are a luscious blue-green, deep blue and black. There can be some variation on this and I have included an image of a brownish-orange juvenile to highlight the possible differences. The front of its notum looks a bit like the toe of a Keen shoe, and it has a velvety soft appearance overall. According to Cory Pittman and Pauline Fiene it feeds on a Blue Bryzoan, Bugula dentata which I have included a few photos of. For the past several years (2014 to 22) we have seen a fairly consistent number of “Gloomies” in the North Kihei, Maui area. For more information and photos of them on their food bryzoan, please see Sea Slugs of Hawaii. To about 3″ or 75 mm.