Despite an astounding paucity of information on population levels anywhere, Ocean Sunfish (Mola mola) was recently listed as vulnerable by the IUCN. The concerns are high levels of by-catch in various fisheries across the globe, and a very limited understanding of population dynamics. Details of sunfish interactions in the Australian and New Zealand longline fisheries have been recorded by fisheries observers for over 15 years, and could hold valuable information on recent population trends in these areas. But which species are caught? Over 200 years of taxonomic confusion has rendered Molidae species identification no easy feat. To determine which sunfish species are caught in the longline fisheries across Australia and New Zealand, Australian Fisheries Management Authority and the New Zealand Ministry for Primary Industries provided us with tissue samples through their longline observer programs. We also used social media to locate stranded sunfish and secure tissue samples. The surprising genetic results have provided an excellent opportunity to review the zoogeography of Australian and New Zealand sunfish, and comment on the uncertainty associated with assessing their population trends and vulnerability to fishing pressure, based on by-catch data.