''Bombus inexspectatus'' is an

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...

bumblebee A bumblebee (or bumble bee, bumble-bee, or humble-bee) is any of over 250 species in the genus ''Bombus'', part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related gener ...

native to Europe.

Distribution and habitat

''Bombus inexspectatus'' occurs in

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

, and

Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...

. The species inhabits high mountain habitats, especially on the southern slopes, in the alpine and subalpine zone in open areas and on the edges of woodland habitat. It occurs in the

Cordillera Cantábrica The Cantabrian Mountains or Cantabrian Range ( es, Cordillera Cantábrica) are one of the main systems of mountain ranges in Spain. They stretch for over 300 km (180 miles) across northern Spain, from the western limit of the Pyrenee ...

and the

Alps The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Sw ...

. populations may also occur in the

Pyrenees The Pyrenees (; es, Pirineos ; french: Pyrénées ; ca, Pirineu ; eu, Pirinioak ; oc, Pirenèus ; an, Pirineus) is a mountain range straddling the border of France and Spain. It extends nearly from its union with the Cantabrian Mountains to C ...

, but its presence there is as yet unconfirmed. This distribution is fragmented, and it is likely that ''B. inexspectatus'' is a relictual species that once occurred more widely but became limited to mountaintops as conditions changed.

Ecology

Like some other bumblebee taxa, this species is a social parasite. It does not produce its own worker bees and cannot maintain its own colony; instead, individuals live inside the nest of another bumblebee species. ''B. inexspectatus'' lives inside the nest of the more common red-shanked bumblebee (''Bombus ruderarius''). It is supported by its host, as it cannot produce the wax used to build nests and it does not have pollen baskets on its legs. Thus, it is an obligate social parasite, one that must be supported by another species, rather than a facultative parasite, which can live on its own if necessary. This species has apparently evolved obligate parasitism separately from the few other taxa that practice it, such as the cuckoo bees (subgenus ''Psithyrus''). This bee is closely related to its host, a condition known as Emery's rule. In fact, the two are sometimes confused because they look so similar. ''B. ruderarius'' is the only known host for this species, but there may be others.

Conservation

The species has been classified as

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

. The bee is already rare with geographically separated populations, and available high-mountain habitat is shrinking due to

climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

. Its parasitic lifestyle also makes it susceptible to indirect damage from population reductions in its host species.

References

{{Taxonbar, from=Q2702503 Bumblebees Hymenoptera of Europe Insects described in 1963