In the last decade, the trade of marine ornamental species has experienced a significant expansion worldwide; however, this industry still relies on a large number of unsustainable practices (e.g., cyanide fishing, overexploitation of target species) and needs to shift its operations urgently to avoid collapsing. Under this scenario, traceability and certification emerge as important management tools that may help this industry to shift toward sustainability. This industry relies on the trade of thousands of small-sized species that are traded live on a unitary basis with high market value. These features, along with a fragmented and complex supply chain, make the traceability of marine ornamental species a challenging task. This study presents the most commonly used methods to trace aquatic organisms and discusses their suitability to trace marine ornamental species. The use of bacterial fingerprints appears to be the most promising method to successfully trace marine ornamentals, but it is most likely that a combination of two or more traceability methods need to be implemented to cover all the unique features displayed by the live trade of marine ornamental species.

Seahorses are currently experiencing an unprecedented level of anthropogenic pressure promoted by habitat destruction and increasing fishing effort to supply premium markets. This study provides an overview of the scientific literature on seahorses in the 21st century and critically discusses five major knowledge gaps and research opportunities to advance the state of the art on this research field. The average number of publications per year increased from 10 (2001–2002) to ∼40 (2001–2015), the majority addressing issues on seahorse ecology, biology, and aquaculture, with the most studied species being Hippocampus kuda, H. guttulatus, H. reidi, H. abdominalis, H. erectus, H. hippocampus, and H. trimaculatus. This study explores the opportunity of using seahorses as flagship species to foster mangrove conservation and decrease trawling fisheries. It also suggests that further scientific studies are needed to better understand and manage the populations of the most heavily traded seahorse species, as well as the need to monitor their vulnerability to emerging pollutants and climate change. Sustainable seahorse aquaculture can play an important role in seahorse conservation, as well as in the development of reliable traceability tools to fight the illegal trade of these highly priced organisms.