Monotypic form, without taxonomic complexities (Baagøe 2001).

A rare species that occurs at low densities and has specific habitat requirements. Its population is fragmented and its sedentary habits mean that it does not colonise new areas easily. There is very little information on population trends, but it is suspected that the species is declining as a result of the loss and degradation of specific types of old-growth woodland, compounded by other threats such as human disturbance. It is suspected that these threats may result in a population decline approaching 30% over a 15 year period including both the past and the future. Consequently it is assessed as Near Threatened (approaching A4c). There is unlikely to be any rescue effect - populations are very structured and based on genetic data there is little interchange.

A western Palaearctic species, it occurs in central and southern Europe and temperate south-western Asia (Caucasus region and Asia Minor). It is found on several islands including Bornholm, Corsica, Elba, Capri, Sicily (Baagoe 2001). It has been recorded from sea level to as high as 1,500 m in central Spain (Benzal and de Paz 1991). Although only a single record has been recorded in central Montenegro, it is possibly present in most of the country (Milan Paunovic pers. comm. 2007)

It is considered rare throughout its range, although in optimal habitat it may be regularly found, and it is a typical member of central European bat communities. In southern Europe and the Caucasus it is rare (K. Tsytsulina pers. comm. 2005), and there has been only one confirmed individual in Iran (Sharifi et al. 2000). There are also few records from Turkey, where it has been found in groups of up to six individuals in six localities (A. Karatash pers. comm. 2007). Breeding colonies are small, numbering up to 10-30 individuals (K. Tsytsulina, J. T. Alcalde, A. Hutson pers. comm. 2006). Populations are fragmented as a result of the loss in historic times of the majority of its forest habitat. There is very little information on recent population trends. However, one of the few colonies known from Spain has disappeared in recent years because of human disturbance (J. T. Alcalde and J. Juste pers. comm. 2006).

This species has specialised habitat requirements, and is largely dependent on mature natural forests. In the south-west Asia region it is found in broadleaf forest and sometimes mixed forest (K. Tsytsulina pers. comm. 2005). In Europe, it tends to prefer mature deciduous woodland of beech and oak with a high proportion of old trees. Densities of this species are highest in forests that are managed according to environmental (rather than strictly economic) principles. It is occasionally found in artificial habitats such as pasture, plantations (especially orchards) and rural gardens. In summer it roosts in tree-holes, or occasionally in buildings; bird and bat boxes are fairly readily accepted (Schlapp 1999). In winter it hibernates in underground habitats, and possibly also in hollow trees. It forages in woodland and along woodland edge for Lepidoptera, Diptera, Planipennia, and also non-flying insects. A sedentary species (Hutterer et al. 2005).

Threats include inappropriate management and development of woodland habitats, intensive agriculture (e.g., use of pesticides on farmland adjacent to woodland occupied by the species) and human disturbance of roost sites. The loss of old trees with hollows is a particular problem. In Germany, infrastructure developments (and associated habitat fragmentation) and forestry are the main threats (Schulenberg 2005).

It is protected by national legislation in most range states. There are also international legal obligations for its protection through the Bonn Convention (Eurobats) and Bern Convention. It is included in Annex II (and (IV) of EU Habitats and Species Directive, and hence requires special measures for conservation including designation of Special Areas for Conservation. There is some habitat protection through Natura 2000, and the species is found in protected areas all over its range. It benefits directly or indirectly from a number of LIFE funded projects in Europe, and there are current research projects focussing on the species. Appropriate habitat management involves leaving old trees in sufficient numbers, as each individual colony uses up to 30 trees in the summer. Monitoring is required to determine population trends in this species.