Recent findings of the deep–sea fish species Tetragonurus cuvieri Risso, 1810 and Notacanthus bonaparte Risso, 1840 (Chordata, Teleostei) in Southwestern Europe (Gulf of Cádiz, SW Spain)

Two specimens of the deep–sea fish Tetragonurus cuvieri Risso, 1810 and Notacanthus bonaparte Risso, 1840 were captured in the Gulf of Cadiz on January 2023 at a depth of 14.15 m and on March 2023 at a depth of 532 m, respectively. The identity of the specimens was verified using both morphological and genetic criteria. In this study, we compile information on the global occurrences of these two deep–see species, and they are uncommonly observed in these shallow waters of the Iberian Peninsula. It highlights the importance of conducting further research to understand the full range of species inhabiting these shallow waters. The presence of these species can provide insights into the environmental conditions and specific habitats within the Gulf of Cádiz, as these fish are often associated with particular depth ranges and oceanographic features.