The Phantom Nudibranch: this sea slug's body is almost completely transparent, revealing the delicate network of organs within
The scientific name of this species is Melibe colemani, and it's regarded as one of the most elusive nudibranchs in the world. It's also known as the phantom nudibranch (or ghost nudibranch) because its body is largely transparent, and the sea slug's digestive glands are clearly visible. The network of glands make it look almost like a mass of tangled yarn.
Above: the outline of the nudibranch's head is visible toward the upper left-hand corner of this photo
These strange-looking creatures can measure up to 5cm long, and they're typically found on the coral reefs that surround the Philippines, Indonesia, and Malaysia.
Above: close-up of the sea slug's head, showing a pair of rhinophores (which look like bunny ears) and an oral hood/mouth
The phantom nudibranch actively hunts smaller molluscs and crustaceans, using an expandable oral hood to capture and ingest its prey. The sea slug's head is also equipped with a pair of rhinophores, which are chemosensory organs that resemble eyestalks or "bunny ears;" the rhinophores can detect chemicals in the surrounding environment, allowing the nudibranch to find prey and locate other members of the same species.
Above: a phantom nudibranch with its oral hood stretched open
This species was discovered by an underwater photographer named Neville Coleman in 2004, and it was formally described eight years later.
Sources & More Info:
Systematics and Biodiversity: Diversification of Filter-Feeding Nudibranchs: Two Remarkable New Species of Melibe
Reef ID Books: Melibe colemani, Iconic Nudibranch
The Slug Site: Melibe colemani
Nudibranch Domain: Melibe colemani
Bubbles Underwater & Beyond: Melibe colemani, the Grail of Nudibranchs
