This study provides the first micro-thermometric data of fluid inclusions in mafic loose xenocrysts and ultramafic xenoliths in explosive products of the melilitite-carbonatite Mt. Vulture volcano (southern Italy). We found within ultramafic xenoliths CO2-dominated fluid inclusions with trapping pressures between 8.5 and 8.9 kbar, corresponding to a depth of 26-27 km, in proximity of the local crust-mantle boundary. In contrast, trapping pressures within the loose xenocrysts are up to 2.8 and 3.2 kbar (8-9 km). We estimated an ascent rate of the latest 141 ka old melilititic-carbonatitic magmas from the Moho depth to the surface in the range of few hours. Considering the ongoing degassing of mantle-derived CO2 rich gases at Mt. Vulture, together with geophysical evidences of the presence of low amount of melts at depth, and the tectonic control of the past volcanic activity, our study opens new perspective about the hazardous nature of the “quiescent” melilitite-carbonatite volcanoes.