A Red Sea Depth Record of the Coral-Dwelling Crab Opecarcinus (Decapoda: Cryptochiridae) in the Mesophotic Zone

Coral-dwelling gall crabs (Cryptochiridae) are obligate symbionts of stony corals and occur on shallow and deep reefs across the tropical belt. The circumtropical genus Opecarcinus associates with Agariciidae corals, a dominant component of Mesophotic Coral Ecosystems (MCEs). Here, we report the first Red Sea mesophotic record, with 89 m as the deepest record to date, for Opecarcinus-collected from Leptoseris cf mycetoseroides-from the NEOM marine area in Saudi Arabia. This observation reconfirms the depth range flexibility of Opecarcinus species and highlights the need for further mesophotic explorations of reef-associated fauna.