Species, study area & species locations
Four species are particularly known for their link to cold areas and for
their rarity: Bombus alpinus helleri , Bombus mendax ,Bombus mucidus and Bombus konradini . Bombus
(Alpinobombus) alpinus (Linnaeus, 1758) has a disjoint distribution, as
the subspecies alpinus occurs in the high Fennoscandia andhelleri occurs in the Alps at the highest elevation and formerly
in the Carpathians, where it is now considered extinct (Rasmont et al.
2015, Biella et al. 2017). Bombus (Mendacibombus) mendaxGerstaecker, 1869 occurs at the highest elevation of the Alps with the
subspecies mendax (Amiet et al. 2017) and of the Pyrenees with
the subspecies latofasciatus Vogt 1909 (Ornosa et al. 2017), with
a few more records on the Cantabrian mountains(SantamarĂa et al. 2011).Bombus (Mucidobombus) mucidus Gerstaecker, 1869 occupies the
middle and high elevations of the Alps and of the Apennines (Manino et
al. 2007), it occurs in the Pyrenees and it occurs also locally on the
Cantabrian Range (Ornosa et al. 2017) and patchily in the Balkans and
the Carpathians (Rasmont et al. 2015). Bombus (Pyrobombus)
konradini Reinig 1965 (i.e. the central Apennines populations of the
formerly known Bombus monticola konradini ) occurs exclusively at
the high elevations of the central section of the Apennines and little
is known on its ecology (Ricciardelli D’Albore and Piatti 2003).
The study area encompasses the Alps, the Apennines and the Pyrenees.
Occurrence locations were retrieved from the literature, private and
museum collections, with details available in supporting text A1. The
coordinates of the records were visually validated with satellite images
(i.e. corresponding to alpine areas in a broad sense and within the
known elevational range of the species); unlabelled, inconsistent,
dubious or duplicated data were excluded. Cumulatively, 1771 data were
available for the analyses: 172 for B. alpinus , 722 for B.
mendax , 826 of B. mucidus and 50 of B. konradini from the
Alps, Apennines and Pyrenees study areas (we excluded the Cantabrian
Range and Balkans because of too scattered and mostly old records
available from there). As the investigated species are large and
conspicuous, they are unlikely to go undetected and these available
records are representative for describing the distribution with
sufficient accuracy. The datasets used in the analyses constitute the
most comprehensive ones available for the study species.