Background. Microichthys coccoi Rüppell, 1852 was originally described based on a stranded individual collected in the Strait of Messina, Sicily, central Mediterranean. The distribution range of the species is poorly known, as very few individuals have been recorded from Italy, Greece, and Turkey in the Mediterranean, and from the Azores in the north eastern Atlantic. The aim of this study was to report the presence of M. coccoi from the Balearic Islands (western Mediterranean). The history of species’ known records is compiled and its presence in the Atlantic is discussed. Materials and methods. A specimen of M. coccoi was collected from a bottom trawl sampling, carried out at 591 m depth in the south of Mallorca (Balearic Islands) during the survey MEDITS_ES05_17 in June 2017. The fish (a female) was subjected to standard descriptive procedures and subsequently deposited in the collection of the Hebrew University of Jerusalem. Results. Microichthys coccoi is recorded for the first time from the Balearic Islands, which expands its distributional range inside the Mediterranean more than 1000 km westwards. Conclusion. Like the other known specimens, except for those collected in the Strait of Messina, the presently described individual was caught on the slope, confirming that M. coccoi is a deep-water species. The comparison of this fish with Azorean specimens indicated differences in the number of pectoral-fin rays, the most important character distinguishing the species of Microichthys. Hence, further work is necessary to classify the Azorean population, which if confirmed as M. coccoi, would make necessary a modification of the species’ description and if rejected, an additional Atlantic species should be described.

Epigonidae, cardinalfish, morphometry, expanded distribution