A review of contemporary patterns of endemism for shallow water reef fauna in the Red Sea

Abstract

Aim The Red Sea is characterised by a unique fauna and historical periods of desiccation, hypersalinity and intermittent isolation. The origin and contemporary composition of reef-associated taxa in this region can illuminate biogeographical principles about vicariance and the establishment (or local extirpation) of existing species. Here we aim to: (1) outline the distribution of shallow water fauna between the Red Sea and adjacent regions, (2) explore mechanisms for maintaining these distributions and (3) propose hypotheses to test these mechanisms.Location Red Sea, Gulf of Aden, Arabian Sea, Arabian Gulf and Indian Ocean.Methods Updated checklists for scleractinian corals, fishes and non-coral invertebrates were used to determine species richness in the Red Sea and the rest of the Arabian Peninsula and assess levels of endemism. Fine-scale diversity and abundance of reef fishes within the Red Sea were explored using ecological survey data.Results Within the Red Sea, we recorded 346 zooxanthellate and azooxanthellate scleractinian coral species of which 19 are endemic (5.5%). Currently 635 species of polychaetes, 211 echinoderms and 79 ascidians have been documented, with endemism rates of 12.6%, 8.1% and 16.5% respectively. A preliminary compilation of 231 species of crustaceans and 137 species of molluscs include 10.0% and 6.6% endemism respectively. We documented 1071 shallow fish species, with 12.9% endemic in the entire Red Sea and 14.1% endemic in the Red Sea and Gulf of Aden. Based on ecological survey data of endemic fishes, there were no major changes in species richness or abundance across 1100 km of Saudi Arabian coastline.Main conclusions The Red Sea biota appears resilient to major environmental fluctuations and is characterized by high rates of endemism with variable degrees of incursion into the Gulf of Aden. The nearby Omani and Arabian Gulfs also have variable environments and high levels of endemism, but these are not consistently distinct across taxa. The presence of physical barriers does not appear to explain species distributions, which are more likely determined by ecological plasticity and genetic diversity.

Comparative phylogeography of the ocean planet

“…The Caribbean Province has 33% endemism for fishes (10), 32% for decapod crustaceans (11), and 37% for corals (12). In the Red Sea, endemism is 13% for fishes and polychaetes, 8% for echinoderms, 17% for ascidians, and 5.5% for corals (13). This concordance across diverse taxonomic groups indicates unifying evolutionary processes.…”

Metabarcoding Reveals Seasonal and Temperature-Dependent Succession of Zooplankton Communities in the Red Sea

“…The Red Sea is considered unique in terms of its distinctive physico-chemical conditions that include year-round high levels of irradiance, high temperature and salinity levels, and low nutrient concentrations (Acosta et al, 2013;Raitsos et al, 2013). Moreover, it harbors a unique fauna characterized by one of the highest levels of endemism for marine organisms in the world (DiBattista et al, 2016). Historically access to the main body of the Red Sea has been limited and as a consequence whole community studies of zooplankton are scarce and very little is known about the composition and the annual cycle of zooplankton communities in this marine environment.…”

A review of the Callogobius (Teleostei: Gobiidae) from the Red Sea with the description of a new species

“…Even so, the endemism of Callogobius in the Red Sea (28%) is higher than that reported for the region as a whole (13%; DiBattista et al 2015), and is perhaps indicative of the tendency for demersal, egg-guarding species to have more restricted ranges. For example, Pseudochromis (Pseudochromidae) exhibits about 75% endemism in the Red Sea (Gill 2004;Golani & Bogorodsky 2010).…”