Catalogue of Bombus wurflenii Radoszkowski, 1860 (Hymenoptera, Apidae) specimens deposited in the State Museum of Natural History NASU, Lviv, Ukraine

Abstract

Bombus wurflenii Radoszkowski, 1860 belongs to the subgenus Alpigenobombus and is one of the 40 bumblebee species that occur in Ukraine. This Boreal-Alpine species has a disjunctive range and is confined to the mountains and hills of Europe. It occurs in Scandinavia, in central and southern Europe (the Cantabrian Mountains, the Pyrenees, the Alps, the Apennines, the Balkans, the Carpathians). It is also known from the far east of Europe (the Ural Mountains), and from the north-eastern Turkey and the Caucasus (Rasmont, Iserbyt, 2010-2012; Rasmont et al., 2015). All scenarios of future distribution of Bombus wurflenii project a moderate reduction of suitable areas by 2050. By 2100 the climatic niche space of the species would be even more restricted. With low dispersal capability and since Bombus wurflenii is a specialized species linked to cold boreal and alpine-subalpine conditions, it would suffer substantially from global warming (Rasmont et al., 2015). Bombus wurflenii is a medium sized bumblebee. It is highly adapted for “nectar robbing”, i. e. perforating holes at the base of long flower corollas to reach the nectar. To do this, it uses its modified mandibles, each with six denticles on outer margin . In Ukraine the species is represented by the subspecies B. wurflenii mastrucatus Gerst. and occurs in the Ukrainian Carpathians only. It inhabits mountain forests from a height of 500 m a. s. l. to the subalpine zone inclusive. The highest number of population of the species is observed within the altitude range of 800-1100 m above sea level (Konovalova, 2010). B. wurflenii is nesting underground, using the abandoned nests of rodents in beech, beech-spruce and spruce forests, in polonynas, meadows and also on rocky slopes in the subalpine. The emergence of queens from hibernation happens in late spring and early summer. The development of small colonies lasts until July-August, culminating in the emergence of new reproductive generation. In the Carpathian highlands B. wurflenii is considered a common one. However, during last decades, the destruction of both nesting sites and forage flora of this species due to excessive recreational pressure, is a serious factor threatening the persistence of its population. For this reason, B. wurflenii has been included into the Red Book of the Ukrainian Carpathians as vulnerable one, also taking into account a relatively limited area inhabited by populations of the species. The species plays a significant role in the pollination of high mountain flora. A feeding diet of this bumblebee in the Ukrainian Carpathians includes at least 23 plant species belonging to 16 families (unpublished data of the author). Among its favourite forage plants are: Centaurea phrygia subsp. carpatica (Porcius) Dostál, Cirsium waldsteinii Rouy, Gentiana asclepiadea L., Rhododendron kotschyi Simonk., Vaccinium spp., Aconitum spp. In the entomological collection of the State Museum of Natural History, National Academy of Sciences of Ukraine, 42 specimens of B. wurflenii have been deposited. Only one specimen belongs to an old historical collection. It was collected from the Tatry Mts. in Poland on 30.07.1905 and identified by J. Snieżek. From the present territory of Ukraine B. wurflenii was recorded for the first time in 1939 in Chornohora mountain range, at an altitude of 1500 m a.s.l. (Fudakowski et al., 1939). The recent part of the collection includes specimens, found from 2000 to 2006 in mountain regions of Ivano-Frankivska and Zakarpatska provinces of Ukraine (fig. 1). The recent collection of B. wurflenii represents all three castes of the species: 1 queen, 32 workers and 8 males. Bumblebees were collected during June, July and August within altitudes of 800-1700 m a.s.l. in the following physiographic regions: UC: PlChr: Chornohora massif; UC: PlChr: Svydovets massif; UC: OCVV: Gg: Outer Gorgany range. The vast majority of specimens have been collected in protected territories: Carpathian Biosphere Reserve (Chornohora protected massif, Svydovets protected massif) and Carpathian National Nature Park.