Amphibious mudskipper populations are genetically connected along coastlines, but differentiated across water

Aim: Many mudskippers in the family Gobiidae are obligately amphibious, requiring both aquatic and terrestrial portions of their life cycle. The terrestrial phase involves restrictions to mudflat habitats during breeding, when adults build burrows in the mud to lay eggs. The effects of this restricted out-of-water phase might be reflected in the population structure of the species. However, dispersal during the aquatic larval phase could connect distant populations. We examine one such mudskipper, Periophthalmus modestus, to test whether populations separated by water are more differentiated than those connected along a coastline.
Location: South and East China Sea
Taxon: Periophthalmus modestus (family: Gobiidae, subfamily: Oxudercinae) (Cantor 1842)
Methods: We collected 236 individuals from ten locations around the East and South China Seas. We used a targeted capture sequencing method, RADcap, to call SNPs from 365 loci. We used multiple spatial and population genetics analyses and ...