Data from: Population structure and dispersal of the coral excavating sponge Cliona delitrix

Some excavating sponges of the genus Cliona compete with live reef corals,
often killing and bioeroding entire colonies. Important aspects affecting
distribution of these species, such as dispersal capability and population
structure, remain largely unknown. Thus, the aim of this study was to
determine levels of genetic connectivity and dispersal of Cliona delitrix
across the Greater Caribbean (Caribbean Sea, Bahamas and Florida), to
understand current patterns and possible future trends in their
distribution and effects on coral reefs. Using ten species-specific
microsatellite markers, we found high levels of genetic differentiation
between six genetically distinct populations: one in the Atlantic
(Florida-Bahamas), one specific to Florida and four in the South Caribbean
Sea. In Florida, two independent breeding populations are likely separated
by depth. Gene flow and ecological dispersal occur among other populations
in the Florida reef tract, and between some Florida locations and the
Bahamas. Similarly, gene flow occurs between populations in the South
Caribbean Sea, but appears restricted between the Caribbean Sea and the
Atlantic (Florida-Bahamas). Dispersal of C. delitrix was farther than
expected for a marine sponge and favoured in areas where currents are
strong enough to transport sponge eggs or larvae over longer distances.
Our results support the influence of ocean current patterns on genetic
connectivity, and constitute a baseline to monitor future C. delitrix
trends under climate change.