443.

Anna Tess’s Myotis

Myotis annatessae

French: Murin d'Anna Tess / German: Anna-Tess-Mausohr / Spanish: Ratonero de Anna Tess

Other common names: Anna Tess's Bat

Taxonomy. Myotis annatessae Kruskop & Borisenko, 2013,

“Song Con river valley, Saola Basecamp, Vu Quang, Ha Tinh Province, Vietnam.”

Subgenus Myotis; muricola species group. See M. ater . This species is closely related to M. ancricola, but their relationships with other Myotis are still unclear; limited genetic data suggest a possible link with M. montivagus, M. annectans, and M. rosset, whereas earlier studies found M. annatessae to be close to M. muricola . Populations of China show genetic differences from those of Laos and Vietnam, and may be taxonomically separable. Six specimens from West Bengal were previously attributed to M. muricola . Monotypic.

Distribution. N Vietnam, C Laos, C China (Shaanxi and Guizhou), and NE India (West Bengal).

Descriptive notes. Head-body 37-44 mm, tail 33-8—40- 2 mm, ear 11-5-13- 8 mm, hindfoot 6-8 mm, forearm 32-6-35- 3 mm; weight 2-9- 4-8 g. Anna Tess’s Myotis differs from the Valley Myotis ( M. ancricola)in somewhat lighter pelage, longer tibia, and smaller skull on average. Fur is moderately thick; dorsally grayish brown (hairs blackish basally, gradually becoming brown toward tip); ventrally slightly paler (hairs with blackish base, brown middle section, and silvery whitish tip). Bare face, ears, and membranes are medium brown. Ears moderately long with bluntly pointed tips and weak notch on posterior margin; tragus is just under half ear-height and is bluntly pointed. Wings attach at base of outer toe; calcar is unkeeled. Baculum is short (c. 0-7 mm long) and saddle-shaped; lateral sides converge forward and the anterior end is blunt; there is no constriction on anterior third, and tip curves downward; overall it is less robust than in the Valley Myotis, and has a prominent basal notch. Skull is small with low, narrow rostrum, bulbous braincase, and concave frontal region; sagittal crest is reduced, lambdoidalcrests are visible but weak. Canines are small and both C' and C, are only slightly taller than their respective anterior premolars; all upper and lower premolars are within tooth row; lower molars are myotodont.

Habitat. Found around large rivers in mountain foothills, at elevations of 200-1300 m.

Food and Feeding. Anna Tess’s Myotis has been observed foraging 1-7 m above water.

Breeding. No information.

Activity patterns. Calls are a steep FM sweep, with peak frequencies of 45-50 kHz (Vietnam).

Movements, Home range and Social organization. No information.

Status and Conservation. Not assessed on The IUCN Red List, due to its recent recognition as a species. Virtually nothing is known.

Bibliography. Kruskop (2013a), Kruskop & Borisenko (2013), Kruskop, Borisenko et al. (2018), Ruedi et al. (2015).