Figure 1.

Map indicating collection sites for reef fishes sampled in the Red Sea and Arabian Sea including eight regional endemics (indicated by asterisks) and two widespread species. Colored circles indicate the proportion of samples per species at a site as indicated by the key; circle size is scaled by sample size. Major oceanographic currents and features are represented by arrows. Three putative barriers to larval dispersal are outlined by opaque orange solid lines: b1, 17°N in the Red Sea; b2, Strait of Bab Al Mandab between the Red Sea and Gulf of Aden; and b3, monsoonal upwelling system in the Arabian Sea