Updated list of bumblebees (Hymenoptera: Apidae) from the Spanish Pyrenees with notes on their decline and conservation status.

The Pyrenees, where Euro-Siberian, Mediterranean and alpine faunas join together, have a large biodiversity of bumblebees. We compiled historical literature records of bumblebee species from the Spanish Pyrenees, and then compared these to contemporary surveys to assess trends in elevational distribution. Twenty-eight species (including thirty-five subspecies) were found in the contemporary survey. Nine species and two subspecies previously present were not detected, some included on the Spanish Red List. With the exception of a few species, a reduction of the altitudinal range and an orophilous tendency was observed at both upper and lower elevational levels, suggesting an upward trend towards better-preserved high areas. Our results reinforce the need to develop new protection programs and more restrictive conservation measures for bumblebee populations, species and their habitats.