The first ciguatera fish poisoning (CFP) in Portugal dates from 2008 when 11 people reported CFP symptoms after consuming a 30 kg amberjack caught around the Selvagens Islands (Madeira Archipelago). Since then, 49 human poisonings have been reported. The emergence of a new threat challenged scientists and regulators, as methods for toxic microalgae analyses and ciguatoxin (CTX) detection were not implemented. To minimise the risk of ciguatera, the Madeira Archipelago authorities interdicted fisheries in Selvagens Islands and banned the capture of amberjacks weighing more than 10 kg in the entire region of Madeira Archipelago. The accurate identification and quantification of the benthic toxin-producing algae species spreading to new areas require efforts in terms of both microscopy and molecular techniques. Two ciguatera-causing dinoflagellates, Gambierdiscus excentricus and Gambierdiscus australes, were identified in the Madeira Island and Selvagens sub-archipelago, respectively. Regarding the CTX analysis (N2a cell-based assay and LC-MS) in fish, the results indicate that the Selvagens Islands are a ciguatera risk area and that fish vectoring CTX are not limited to top predator species. Nevertheless, advances and improvements in screening methods for the fast detection of toxicity in seafood along with certified reference material and sensitive and selective targeted analytical methods for the determination of CTX content are still pending. This study aims to revise the occurrence of ciguatera cases in the Madeira Archipelago since its first detection in 2008, to discuss the risk management strategy that was implemented, and to provide a summary of the available data on the bioaccumulation of CTX in marine fish throughout the marine food web, taking into consideration their ecological significance, ecosystem dynamics, and fisheries relevance.

The dinoflagellate genus Gambierdiscus was detected for the first time in the Azores Archipelago, representing its northernmost record to date (> 39°N). Two strains were isolated from macroalgal substrates on Corvo and Faial Islands during the summer of 2024, coinciding with a marine heatwave in which sea‐surface temperature anomalies exceeded +2°C. Morphological and molecular analyses identified both isolates as Gambierdiscus carolinianus , extending further North the known range of this genus in the Atlantic and complementing previous records from other Macaronesian archipelagos. The Azorean isolate from Corvo clustered more closely with western Atlantic populations than with Madeira or the Canary Islands strains, suggesting long‐range connectivity potentially driven by oceanographic processes. Although no ciguatera poisoning (CP) cases have been reported in the Azores, the occurrence of Gambierdiscus highlights the need for sustained monitoring and ecological assessments to evaluate the risk of CP emergence in this remote temperate archipelago under shifting environmental conditions.