The taxonomy of the genus
Myotis is "considered to be one of the most challenging topics in European bat systematics", and the species count within the genus and the
M. mystacinus group has varied considerably over the years. The analysis of morphological, behavioural, and especially genetic characters have since identified further
cryptic species of whiskered bats in the genus
Myotis, including
Myotis alcathoe (described in 2001 from Europe).
Myotis aurascens and
Myotis ikonnikovi are other similar species.
Myotis hajastanicus was also included in
M. mystacinus until recently, but it was differentiated on the base of morphological comparison. As of 2016, three subspecies are accepted: •
M. m. mystacinus, found over most of its range, •
M. m. occidentalis, found in Iberia and Morocco, •
M. m. caucasicus, found in the
Caucasus. == Description ==