Palm ruff ( Seriolella violacea , Guichenot 1848) has been identified as a promising candidate for aquaculture in northern Chile. During the winter of 2023, an outbreak of an external infectious disease affected 3740 juvenile Palm ruff at the Marine Fish Farming Laboratory of the Universidad Católica del Norte. The macroscopic signs, particularly external ulcers, were consistent with tenacibaculosis. Microbiological, genomic a...