A long awaited description has finally been done by T. Görföl and his colleagues – a new species of Hypsugo was already mentioned as Hypsugo sp.A in their SE Asian bat barcoding study by Francis et al. in 2010. The species can be readily distinguished from all other SE Asian congeners by its blackish pelage and conspicuously long canines; hence its name H. dolichodon, Long-toothed Pipistrelle. It resembles to H. pulveratus, a widely distributed species in Indochina and although H. dolichodon is presently known from Vietnam and Lao PDR only, it is worth to check previously collected materials as its distribution area may not be limited to the known territory!
TAMÁS GÖRFÖL, GÁBOR CSORBA, JUDITH L. EGER, NGUYEN TRUONG SON & CHARLES M. FRANCIS (2014). Canines make the difference: a new species of Hypsugo (Chiroptera: Vespertilionidae) from Laos and Vietnam. Zootaxa 3887 (2): 239–250
The article can be downloaded here