Species richness, sampling bias and phylogenetics in deep-sea mussels

Mussels have been thoroughly studied to understand the evolutionary history of symbiont-bearing organisms living in deep-sea reducing environments. However, most conclusions regarding habitat use and evolution of symbiosis have been drawn from datasets that have recently proved strongly biased toward vent and seeps species. We address herein, from available molecular data, the species diversity of deep-sea mussels across environments and localities. The results confirm the need to analyse more species from organic falls. Various sampling strategies and their possible impacts on phylogenetic patterns are discussed.