Nguyen Xuan Dang

Description of a new species of Myotis (Vespertilionidae) from Vietnam

During the examination of a series of specimens, formerly referred to Myotis montivagus, recently collected in Vietnam and Lao PDR, we found that they differ in several important ways from any species formerly included in M. montivagus. We describe them as a new species characterised by a relatively long forearm, moderately long ears, flat cranial profile and wide anteorbital bridge. Based on characters classically used to separate the ‘subgenera’ of Myotis the new species shows affinities to both the nominate subgenus ‘Myotis’ and ‘Selysius’. Our morphological investigations support recent phylogenetic analyses showing that the former ‘subgenera’ of Myotis are in fact paraphyletic groups, even within Southeast Asia. Nevertheless, many of the external and craniodental features formerly used to separate these subgenera provide a practical means of grouping species. Using these characters we provide an identification key to identify the new species, as well as other currently recognized medium and large sized, small-footed Myotis species from the Indomalayan Region.

New genus and species of stripe-bellied rat Pseudoberylmys muongbangensis Tran. H. H., T. H. Viet, L. X. Canh, N. X. Dang, 2008 gen.sp.nov. (Mammalia, Rodentia, Muridae) from Vietnam

After researching clearly about the appearance characteristics, form and microstructure of hairs, skull structure and form of 8 strange rat specimens and compare it with these other big rats of Vietnam, the authors has affirmed that this is a new genus and new species of rat and named that: New genus: Pseudoberylmys Tran. H. H, T. H. Viet, L. X. Canh, N. X. Dang, 2008 gen.nov. New species: Pseudoberylmys muongbangensis Tran. H. H, T. H. Viet, L. X. Canh, N. X. Dang, 2008 gen.sp.nov. Type material : Eight animals was collected during six years from 2002 to 2008. One Holotype with the number 2002-10-T3, 7 Paratype with the number 2003-02-T2, 2003-11-T5, 2004-04-T6, 2006-03-T2, 2007-10-T3, 2008-05-T4 and 2008-11-T7 are deposited in Vietnam Cryptozoic and Rare Animals Research Centre. Type locality : Soc village, Muong Bang commune, Phu Yen district, Son La province, Vietnam. Habitat : Pseudoberylmys muongbangensis Tran. H. H, T. H. Viet, L. X. Canh, N. X. Dang, 2008 gen.sp.nov. was found in the manioc field. Etymology : The new species was named after the commune Muong Bang, where the species was first found. Skull measurement: Occipitonasal length 51.8 - 56.4 Length of auditory bulla 8.0 - 8.7 Length of rostrum 17.8 - 20.5 Breadth of rostrum 12.8 - 14.7 Length of nasal 22.0 - 23.5 Zygomatic breadth 25.6 - 26.9 Length of bony palate 28.4 - 30.2 Interororbital breadth 7.5 - 8.0 Length of incisive foramina 10.5 - 11.2 Breath of braincase 19.5 - 21.2 Length of diastema 15.2 - 16.7 Zygomatic plate breadth 5.2 - 5.9 Leng of interparietal middle 6.5 - 7.5 Foramina insicive breadth 3.4 - 3.9 Length of toothrow maxilla 9.5 - 10.2 Breadth of greatest molar 2.6 - 2.8 Stripy-bellied rat’s skull have many points like with the Berylmys bowersi’skull: long and tapering rostrum, length of nasal bone is longer than 1/3 occipitonasal length, make up a triangular form which project to front and hide the incisors, reduce at rearward and fit in frontal bone to create an V shape. Frontal bone is strait, frontal and parietal joins is arched, parietal edge is short and don’t emerge, the lacrimal bone is very small. In profile of skull, the occiput is a incline plane which project to rearward. Below surface: Auditory bulla is big and bloat. The length of it is longer than 15% length of occipitonasal. Compare with the length of occpitonasal, length of bony palate is roughly 53.22% to 53.68%, length of diastema is roughly 28 to 19% and length of incisive foramina is roughly 19 to 20%. Description: The stripe-bellied rat belonging to the gray rat group in Vietnam. Its length of head and body is 220-260 mm, length of tail is 240-290 mm, length of hind feet is 50-55 mm, length of ears is 29-34 mm and mammals is 2-2 = 8. The pelage is coarse, but not spiny which have two kind of hair: 71-76% is soft underhairs, 24-29% is overhairs. In general, back is grizzled grayish-brown, made of many big overhairs beyond the overhairs which are gray at proximal and black at distal and overhairs is grayish white at proximal, blackish at medial and brownish yellow or dirty white at distal. Darker in the midline of back, paler on flanks to belly. The flanks is more speckled than back so flank’s color become more brownish than dorsal surface. Belly hairs (both overhairs and soft underhairs) are pure white, color of belly is sharply dimarcated from that of back. Specially that, the midline of belly skin from inguinal to breastbone is bare, flesh color with many across wrinkles which haven’t known its biological role. The midline wide is about 1/10 the belly wide. The colour of outside limbs is the same of flanks, inside color is the same of belly. Digits and dorsal surface of the hands and hind feet covered by white short hairs, but the midline dorsal surface of hind feet covered by blackish brown hairs. Tail is much longer than combined length of head and body, round in cross-section, bicolored (dark gray above, dirty white below) and near tip is whitish or pure white. Maxilla toothrow is long and medium size, The incisors are big, in profile is perpendicular with above nasal bone plane. Dental is strong, all of condyloit process, angular processes, coronoit processes develop very much. Differential diagnosis Based on these description and skull measurements, the new species - stripe-bellied rat can be distinguished from Berylmys bowersi, Leopoldamys edwardsi, L. sabanus, Bandicota indica and Dacnomys millardi .

The status of indochinese grey langur Trachypithcus crepusculus at Xuan Lien nature reserve, Thanh Hoa province

Field surveys and interviewing local residents and forest rangers from 2013 to 2015 in Xuan Lien Nature Reserve have recorded 7 groups/troops of Indochinese grey langur (5 groups were sighted and 2 groups recorded by from interview). Each group consistS of 30-35 individuals as maximum and total of 100-200 individuals of Indochinese grey langurs was estimated to exist in the reserve. For all recorded groups, each group consists of at least on adult male, several adult females and sub-adults, and four groups have juveniles. The langurs were found in 4 little-affected forest types (Limestone evergreen forest, Sub-tropical evergreen forest, Lowland evergreen forest and Mixed wood-bamboo forest) located in 8 forest compartments which are situated far away from human settlements. The population of Indochinese grey langur in Xuan Lien NR is among the largest populations of this species in Vietnam. The population is facing with many threats such as wildlife hunting/trapping; Forest habitat degradation; Illegal timber poaching; Habitat disturbance by illegal encroachment of local residents and free-ranging cattle raising. Recommended measures for conservation of the langur population in Xuan Lien NR includestrengthening enforcement of forest and wildlife protection laws; promotion of natural regeneration of forest habitat; awareness education for local residents; monitoring of the langur population and habitat state; study of the species ecological requirement and investigation of Indochinese grey langur population in adjacent Pu Hoat Nature Reserve for collaborative actions on the species conservation.

Results of the survey of the mammal fauna in the Tamdao national park, Vinhphuc province

Rapid assessments of the mammal fauna in the Tamdao national park (NP) were conducted in December of 2004, January and May of 2005 through village interviews and extensive field investigations. Eight (8) large mammal species were reported to be extirpated from the Tamdao NP. Seventy-four (74) mammal species were recorded to be existing in the Tamdao NP. A new checklist of 77 mammal species belonging to 24 families,18 orders was compiled. Out of these 77 recorded species, 21 species were of conservation concern, including 16 nationally threatened species, 17 globally threatened species and 16 species enlisted in the Government Decree 48/2002/NDCP. Current threats to mammal fauna in the Tamdao NP were illegal wildlife hunting, wildlife trade, exploitation of forest products, forest fire and domestic cattle raising.

The first record of living “Fossil” species (Laonestes aenigmanus) in Phong Nha - Ke Bang, Quang Binh province, Vietnam

Laotian Rock Rat Laonastes aenigmamus was first discovered in Hin Nammo NBCA, Khammoune Province, Lao PDR in 2005 by Jenkins et al. (2005). This species was later recognized as living species of the ancient family Diatomyidae which was thought to be extinct since the Miocene, about 11 millions years ago. Conservation of this species is recommended at the highest priority not only due to its limited range but also due to its status as the single living representative of an ancient family. During biodiversity survey on small mammals in Phong Nha - Ke Bang National Park, Quang Binh Province, Central Vietnam, we obtained 4 specimens of un-usual small animals in Thuong Hoa Commune, Minh Hoa District, Quang Binh Province. Based on analysis of appearance, body measurements and skull charasters of these specimens, we confirm that they belong to Laotian Rock Rat Laonastes aenigmamus which was described in 2005 based on specimens collected in Hin Nam No National Biodiversity Conservation Area, Khammoune Province, Lao PDR . Morphological features and some ecological attributes of this species are provided. This species is proposed to be included in the Checklist of wild mammal species of Vietnam under name as Truong son Rat (Annamite Rat). Main threats to Annamite Rat in Vietnam are wildlife hunting/snaring and forest destruction. Snaring small mammals for food and for trade is common habit of local residents in Thuong Hoa and nearby communes. Urgent conservation actions and further studies on population genetics and ecology of this elusive species are recommended.

Preliminary survey results of the mammal species composition of the Xuan Son national park, Phu Tho province

Preliminary survey results of the mammal species composition of the Xuan Son national park, Phu Tho province