This relatively large smooth pale-bodied nudibranch, or shell-less sea slug, is fairly common in the waters of the Red Sea, the Indian Ocean, and the Arabian Sea. Its binomial name was given in 1904 by Sir Charles Norton Edgecumbe Eliot, a British diplomat, colonial administrator, and botanist who came across them in Kenyan waters during his term as Commissioner of British East Africa, from 1900-1904. The present photograph was taken at Old Club Reef in Qatar, at a depth of approximately 15m. The dive site, which was created from wreckage and reef balls in the 1970s, now serves as an artificial reef that lays on the sandy bottom. It is nestled in the east of the country between Umm Said and the Sea Lion Beach Resort and tends to attract a variety of fish, like the yellow bar angel fish. On warmsummer days when the fish tend to head for deeper and somewhat cooler water, these nudibranchs can often be seen on the wrecks or even on the sand around them. (Photograph taken in August 2014 by Erik Van Wellen, DEME, Zwijndrecht, Belgium.)