Abstract
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.
The research expedition was funded by NEOM. The material and KAUST team logistics and molecular analyses were supported by KAUST (award FCC/1/1973-50-01 and baseline research funds to F. Benzoni). G. Chimienti was supported by the Italian Ministry of Education, University and Research (PON 2014–2020, Grant AIM 1807508-1, Linea 1). This research was undertaken in accordance with the policies and procedures of the King Abdullah University of Science and Technology (KAUST). Permission relevant for KAUST to undertake the research was obtained from the applicable governmental agencies in the Kingdom of Saudi Arabia. We thank NEOM for facilitating and coordinating the Red Sea Deep Blue expedition and, specifically, in addition to A.A.E., Thamer Habis, Justin Myner, Paul Marshall, Giacomo Palavicini, Peter Mackelworth, and Abdulaziz Alghamdi. We want to thank OceanX and the crew of OceanXplorer for their operational and logistical support for the duration of this expedition. In particular, we would like to acknowledge Andrew Craig, Olaf Dieckoff, and Ewan Bason for sample collection and OceanX for support of scientific operations on board OceanXplorer. We also wish to thank OceanX Media for documenting and communicating the scientific outcomes of the RSDB expedition with the larger public. Finally, we thank the KAUST Sanger Sequencing Core Lab for helping with sequencing.
