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Nembrotha aurea -

This species is found in the western Indian Ocean, off the coast of Tanzania, as well as in the Pacific. 

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Nembrotha megalocera - This exotic-looking sea slug is confined exclusively to the Red Sea.

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Nembrotha kubaryana -

This species occurs in the tropical Indian and Pacific oceans.

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Nembrotha cristata -

Likewise, the teeming reefs of the tropical Indian and western Pacific oceans are where you'll find this sea slug.

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Phyllidia varicosa -

This species is widely distributed throughout the Indian Ocean, the central Pacific Ocean, and the Red Sea.

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Phyllidia ocellata - This species is confined to the biogeographical regions of the central Indo-Pacific Ocean, from Malaysia to the Solomon Islands, and Indonesia.

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Goniobranchus tinctorius - A Red Sea resident, this species is also found in waters off the coast of Oman.

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Goniobranchus kuniei - Discovered off New Caledonia, this delicate species is widely distributed throughout the western Pacific Ocean and the eastern Indian Ocean.

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Hypselodoris bullockii - This lovely species is widespread and mostly spotted in shallow water in the central Indo-Pacific biogeographical region.

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Hypselodoris kanga - This elegant species has been recorded off the coasts of Tanzania and Mozambique, and throughout the Indian Ocean.

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Hypselodoris apolegma - The tropical western Pacific Ocean is where you'll come across this handsome species.

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Chromodoris annae - Malaysia, Indonesia, and the Philippines to the Marshall Islands are the spots to spy this slinky sea slug.

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Chromodoris dianae - This species has been spotted in the Philippines, Indonesia, and Borneo.

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Chromodoris magnifica - Indonesia and the Philippines to New Guinea and eastern Australia is where this sea slug species resides.

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Hexabranchus sanguineus - The tropical and subtropical waters of the Indo-Pacific biogeographical region are the domain of this species, from Africa to Japan.

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Doriprismatica atromarginata -

Likewise, the tropical and subtropical waters of the Indo-Pacific biogeographical area is also the preferred habitats of this species.

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Fryeria rueppelii - Widely distributed throughout the Red Sea, this species has also been reported in the Gulf of Oman.

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Ardeadoris egretta - Found in the Great Barrier Reef, the species also occurs in the Indian Ocean and the tropical western Pacific in Malaysia, Indonesia, and the Solomon Islands.

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Glaucus atlanticus - This species is found around the east and south coasts of South Africa, European waters, the east coast of Australia, and Mozambique.

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Halgerda okinawa -

This species is found in waters off Japan's Okinawa Prefecture, and from Sulawesi and Alor Island in Indonesia to East Timor and the Philippines.

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Costasiella kuroshimae -

The Japanese islands of Kuroshima, Taketomi, Okinawa, and Ryukyu are home to this species, whose face resembles that of a horned beast.

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Trinchesia yamasui -

Look for this textured species on reefs off Okinawa, Japan.

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Peltodoris atromaculata -

This spotty sea slug species is found almost exclusively in the Mediterranean Sea.

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Felimare cantabrica - Found in the eastern Atlantic Ocean, especially in the Bay of Biscay, and off the Atlantic coasts of Spain and Portugal.

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Felimare picta - The rocky seabeds of the Mediterranean Sea, the North Atlantic, and the Gulf of Mexico are the marine habitats of this species.

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Flabellina verrucosa - This species commonly inhabits areas off the west coast of North America, from southern Alaska to northern Washington state.

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Hermissenda crassicornis - You'll find this particular sea slug in waters off Alaska's Kodiak Island, all the way to northern California.

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Dirona albolineata -

This species is distributed throughout the eastern Pacific Ocean, from Alaska to California.

See also: Ferocious flying insects you don't want to meet

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