Population genetics of a broadcast-spawning coral across a tropical-temperate transition zone reveals regional differentiation and isolation of high-latitude reefs

Aim: Genetic connectivity is a key component of species resilience to climate change in terms of recovery capacity following disturbance and capacity to disperse to novel locations as the climate warms and isotherms shift poleward. We aimed to strengthen our understanding of resilience in this context by characterizing patterns of connectivity and genetic diversity in a broadcast spawning coral across a tropical-temperate transition zone. We hypothesize genetic differentiation between tropical and temperate populations and decreasing genetic diversity with higher latitudes.

Location: Western Australia (WA).

Taxon: Turbinaria species complex. Turbinaria reniformis Oken, 1815 (Dendrophylliidae).

Methods: Samples from 930 target corals were collected from ten locations between 13 - 32 o latitude spanning a 9° C mean temperature range. In-situ species identification of T. reniformis is hindered by morphological plasticity and homoplasy with sister species. We combined Sanger sequen...