[This article is from issue # 38 of the newsletter BioNews, produced by the Dutch Caribbean Nature Alliance (DCNA)—now available online. Among other items, this issue includes articles on Assisted natural recovery of sea urchin populations around Saba and St. Eustatius, Protecting Saba Bank’s Red Hind and Queen Triggerfish Populations, Using Sound to Track Marine Mammals in Saba Bank, and the one mentioned below, Discovery of a new host coral for a Caribbean parasitic crab species.]

Werner de Gier (Naturalis Biodiversity Center) reports that, working in collaboration, scientists from the University of Puerto Rico-Mayagüez, Naturalis Biodiversity Center, and the ANEMOON Foundation have discovered a new host coral for a Caribbean parasitic crab species. De Gire writes, “During one of the scientific expeditions to Bonaire in the Caribbean Netherlands, the scientists found a parasitic gall-crab, Opecarcinus hypostegus, on the previously unknown host coral Agaricia undata (a member of the lettuce corals). With help of DNA-barcoding and pictures taken in the field as well as in the labs, the identity of the coral-inhabiting crab was confirmed. With this record, all species within Agaricia are now listed as hosts of gall-crabs.”

Abstract: The Caribbean scleractinian reef coral Agaricia undata (Agariciidae) is recorded for the first time as a host of the coral-gall crab Opecarcinus hypostegus (Cryptochiridae). The identity of the crab was confirmed with the help of DNA barcoding. The association has been documented with photographs taken in situ at 25 m depth and in the laboratory. The predominantly mesophotic depth range of the host species suggests this association to be present also at greater depths. With this record, all seven Agaricia species are now listed as gall-crab hosts, together with the agariciid Helioseris cucullata. Within the phylogeny of Agariciidae, Helioseris is not closely related to Agaricia. Therefore, the association between Caribbean agariciids and their gall-crab symbionts may either have originated early in their shared evolutionary history or later as a result of host range expansion. New information on coral-associated fauna, such as what is presented here, leads to a better insight on the diversity, evolution, and ecology of coral reef biota, particularly in the Caribbean, where cryptochirids have rarely been studied.

To access full newsletter, see https://www.dcnanature.org/wp-content/uploads/2020/10/BioNews38.pdf

For more information above, see García-Hernández, J.E., de Gier, W., van Moorsel, G.W.N.M., Hoeksema, B.W. (2020). “The scleractinian Agaricia undata as a new host for the coral-gall crab Opecarcinus hypostegus at Bonaire, southern Caribbean.” Symbiosis 81, pp. 303–311(2020): https://doi.org/10.1007/s13199-020-00706-8