Occurrence patterns of coral-dwelling gall crabs (Cryptochiridae) over depth intervals in the Caribbean

Abstract

Coral-associated invertebrates form a major part of the diversity on reefs, but their distribution and occurrence patterns are virtually unstudied. For associated taxa data are lacking on their distribution across shelves and environmental gradients, but also over various depths. Off Curaçao we studied the prevalence and density of coral-dwelling gall crabs (Cryptochiridae), obligate symbionts of stony corals. Belt transects (10 × 0.5m2) were laid out at 6, 12 and 18 m depth intervals at 27 localities. Twenty-one known host coral species were surveyed, measured, and the number of crab dwellings was recorded to study the influence of host occurrence, depth distribution, and colony size on the occurrence rates of three Atlantic gall crab species: Opecarcinus hypostegus, Troglocarcinus corallicola and Kroppcarcinus siderastreicola. The overall gall crab prevalence rate was 20.3% across all available host corals at all depths. The agariciid-associated species O. hypostegus was found to mostly inhabit Agaricia lamarcki and its prevalence was highest at deeper depths, following the depth distribution of its host. Kroppcarcinus siderastreicola, associated with Siderastrea and Stephanocoenia, inhabited shallower depths despite higher host availability at deeper depths. The generalist species T. corallicola showed no clear host or depth specialisation. These results show that the primary factors affecting the distribution and occurrence rates over depth intervals differed between each of the three Atlantic cryptochirid species, which in turn influences their vulnerability to reef degradation.

Holobiont Diversity in a Reef-Building Coral over Its Entire Depth Range in the Mesophotic Zone

“…In the Southern Caribbean, Agaricia undata (Ellis and Solander, 1786) is a dominant coral species between 60 and 100 m depth (Bongaerts et al, 2010(Bongaerts et al, , 2015b, and provides an important habitat for a diverse array of organisms, such as fish (Hoeksema et al, 2017) and crabs (van Tienderen and van der Meij, 2016). Similarly, on the oceanic reefs of Colombia, this species is abundant at lower mesophotic depths (≥60 m).…”

Extreme mitochondrial variation in the Atlantic gall crab Opecarcinus hypostegus (Decapoda: Cryptochiridae) reveals adaptive genetic divergence over Agaricia coral hosts

“…If a male O. hypostegus mates with females on the same coral colony, a genetic preference for that coral host might end up getting fixed in a population. The study on gall crab occurrence rates on the leeward side of Curaçao revealed significant higher O. hypostegus prevalence in A. lamarcki compared to A. agaricites and A. humilis , suggesting a preference for inhabiting A. lamarcki 34.…”

“…1C). This difference may be explained by the higher abundance of A. agaricites corals off Curaçao, compared to A. lamarcki 34, providing suitable habitat closer to the natal site of the O. hypostegus larvae settling on A. agaricites . Furthermore, A. lamarcki has a wider depth distribution than A. agaricites 19, which may influence the isolation-by-distance results.…”

“…Transect data at 6 m, 12 m, and 18 m revealed a depth preference in O. hypostegus for the deeper reefs. Prevalence rates at 6 m were highest in Agaricia agaricites (Linnaeus, 1758) and at 12 m and 18 m highest in Agaricia lamarcki Milne Edwards and Haime, 185134. High genetic diversity was observed at the cytochrome-c oxidase I (COI) gene for the 19 collected specimens obtained from different localities along the Curaçaoan coast, from various depths and five Agaricia coral hosts.…”

Editorial: biodiversity of Caribbean coral reefs (with a focus on the Dutch Caribbean)

“…In addition to professional scientists, students were also accommodated by CARMABI, which resulted in a considerable number of marine biodiversity publications based on graduate school research over five decades (e.g., Roos 1964Roos , 1971Bak 1975;Westinga and Hoetjes 1981;De Weerdt 1984;Van Duyl 1985;Vonk 1988Vonk , 1989Vonk , 1990Meesters et al 1991;Nagelkerken et al 2001;Diekmann et al 2002;Vermeij et al 2003;Dorenbosch et al 2004;Frade et al 2008;Reijnen et al 2010;Snijders and Fransen 2010;Van der Meij 2014;Wolf et al 2014;De Bakker et al 2016;Van Tienderen and Van der Meij 2016;Böhm and Hoeksema 2017;Potkamp et al 2017). In addition, research vessels of the Royal Netherlands Navy performed scientific surveys in the Caribbean and other parts of the Atlantic, such as an expedition to Saba Bank in 1972 ( Van der Land 1977;Hoeksema et al 2011).…”