<p> For over 3.5Ga microbial activities have profoundly altered planetary geochemistry. In particular, sulfur-cycling hydrothermal vent communities have been important players in shaping biogeochemistry and the habitability of Earth. However, the remote nature of deep-sea vents makes investigations challenging. Using the White Point (WP) shallow-sea hydrothermal vent field as a proxy, I employed molecular sequencing, fluorescent in situ hybridization (FISH) and ³⁵S-radiotracer assays to investigate the diversity and function of chemoautotrophic microbial mats. This study revealed a highly active and diverse sulfur-cycling microbial community. Potential epibiotic associations between sulfur-oxidizing (SOxB) and sulfate/sulfur-reducing bacteria (SRB) were identified using FISH. Comparative analyses of 16S rRNA sequences revealed the WP sulfur vent microbial mat community to be similar to deep-sea microbial communities from hydrothermal vents in a range of biotopes and lithologic settings and supported the relevancy of the WP hydrothermal sulfur-vent microbial mats as an excellent model for studying "thiobiotic" vent communities.</p>