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Based on a series of 11 specimens collected in north Vietnam between 2006 and 2007, a new species of tube-nosed bat belonging to the genus Murina is described. Externally similar to Murina aurata Milne-Edwards, 1872, from which it differs primarily in dental characteristics, the new species is distinguished from all other existing species of Murina by a combination of its small size, pelage and craniodental features. It is currently known from three localities in north Vietnam, all of which include significant areas of forest over limestone karst.
Bats constitute a substantial proportion of mammal diversity within the Asian tropics and subtropics and are particularly susceptible to population losses associated with human activities. This poses a conservation concern in Asian karst areas which support high bat species diversity, yet are experiencing habitat loss and degradation and increasing pressure from tourism and extractive industries. As disturbance during crucial reproductive periods (late pregnancy, lactation and weaning) threatens reproductive success, we investigated the reproductive phenology of a bat assemblage at two karst sites in North Vietnam. Our results indicate that the timing of major reproductive events coincides among two cave-dwelling pteropodids, and among 26 cave and foliage dwelling rhinolophids, hipposiderids and vespertilionids. March-July is the primary reproductive period for all insectivorous species sampled, and protection of maternity roosts during this time is critical. Reproduction in cave-dwelling pteropodids spanned a greater period (March-December), due to two birth periods each year. Lactation in the three insectivorous families studied was positively correlated with rainfall and temperature, with weaning occurring during the peak wet season. The strong congruence in reproductive phenologies in our results and climatic homogeneity of North Vietnam (18-23°N) suggests that our study may have wider applicability within the region. Vietnamese caves support high bat diversity which is likely threatened by harvesting for consumption and tourism development nationwide. Studies to investigate and address these threats should be given high priority.
The long-toothed pipistrelle (Hypsugo dolichodon) was recently described as a new bat species based on four specimens from Laos and Vietnam. During investigations of taxa in the Vespertilionini tribe, we noted that specimens reported as Falsistrellus affinis (recently transferred to genus Hypsugo) from Myanmar and Cambodia have mtDNA sequences and craniodental characteristics similar to H. dolichodon and different from genuine H. affinis. Mitochondrial homogeneity within H. dolichodon was also apparent as there was no nucleotide difference between the widely distributed Cambodian, Lao and Vietnamese specimens in CO1 or Cytb genes. Although ecological data are scarce, H. dolichodon appears to be a cave-dweller which would suggest that conservation measures are a priority because tropical caves are under high pressure from human use.
Recent field studies have provided new data for a review of the taxonomy, acoustic characters, distribution, and ecology of two often confused rhinolophid species, which have essentially parapatric distributions in continental Southeast Asia. Rhinolophus coelophyllus is widespread ranging from northern Myanmar to northern Malaysia, eastern Thailand and provisionally western Lao PDR. R. shameli is restricted to eastern Thailand, Cambodia, Lao PDR, and central and southern Vietnam. There are well defined differences in skull morphology, size, and echolocation call frequency, which discriminate between the two taxa.
Rhinolophus affinis sensu lato is a widespread bat species in South and Southeast Asia which shows considerable geographical variation in its morphology, echolocation call frequencies and genetics. The taxonomic status of the taxon in the Sundaic subregion remains uncertain however as the limited studies to date have been largely based on morphology. The aim of the present study was to determine the taxonomic status of subspecific forms recognized in the subregion and to evaluate phylogeographic distinctiveness between those occurring in Borneo and the Malay Peninsula using genetic, morphological and acoustic datasets. Two forms were confirmed: R. a. nesites from Borneo and R. a. superans from the peninsula. The previous recognition of a population from southernmost Sumatra as R. a. superans was not supported, however, as this form is likely R. a. affinis. Genetic divergence between these three forms is rather deep and is estimated to have occurred during the arid climatic period of the Pleistocene when suitable habitats were reduced to isolated pockets. Our results support the phylogeographic distinctiveness hypothesis as R. affinis sensu lato shows discrete affinities between Borneo and the Malay Peninsula. Discovery of new forms of R. affinis is likely with greater sampling effort throughout the region. Our study also demonstrates the importance of employing multiple datasets in taxonomic evaluations, as the use of morphological and/or acoustic datasets alone could lead to erroneous conclusions.
A new species of Kerivoula is described from Seima Biodiversity Conservation Area, Cambodia. It is widely distributed in mainland Southeast Asia, with referred material from 12 additional localities in Myanmar, Thailand, Lao PDR and Vietnam. Superficially similar to Kerivoula flora, it is distinguished by its flattened skull, a character shared with the larger, recently described, Kerivoula kachinensis. It is known from a variety of habitat types, both pristine and disturbed, including deciduous dipterocarp forest, moist evergreen and semi-evergreen forest, forest on limestone karst and upper montane forest.
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