| Within the Vespertilionidae the genus Pipistrellus Kaup, 1829 is characterized by the presence of a calcar lobe (epiblema) attached to the calcar bone, the presence of two upper premolars on each side and a forearm length smaller than 38 mm. Two representatives of this genus occur in The Netherlands: Pipistrellus pipistrellus (Schreber, 1774) and P. nathusii (Keyserling & Blasius, 1839). These two species probably are closely related and are difficult to distinguish. Many authors over the years have used different morphological, dental and skull characters to differentiate these species. In this study the characters are divided into two groups: descriptive characters and biometric characters. Scanning electron photographs indicate a more pronounced... |
