Hypsugo affinis ( Dobson, 1871 )

Saikia, Uttam, Chakravarty, Rohit, Csorba, Gabor, Laskar, Mostaque Ahmed & Ruedi, Manuel, 2025, Taxonomic reassessment of bats from the Western Himalayas, India and description of a new species of the Myotis frater complex (Mammalia, Chiroptera, Vespertilionidae), Zootaxa 5644 (1), pp. 1-78 : 29-30

13. Hypsugo affinis ( Dobson, 1871)

(Chocolate pipistrelle)

New material: 1 M, 19.04.2019, Mandal, Chamoli district , Uttarakhand, V /M/ERS/638; 1 M , 05.05.2021, Mandal, Chamoli district , Uttarakhand, released .

Morphological description of specimen: An adult male had a forearm of 37.9 mm. The pelage appeared uniform smoky black dorsally and smoky greyish brown ventrally ( Fig. 11C ). The head appeared flat; the lip fringes were hairy, ears were small, rhomboidal, and thick at the proximal part with a small tragus. The wings were essentially naked which join at the base of the digits. There were seven caudal vertebrae, the terminal one projecting out of the tail membrane. A prominent calcar lobe was present. Penis was pendulus and hairy on the distal part.

The skull had a broad and elongated rostrum and gradually rised to lambda in a straight line ( Fig. 13A ). There was a midline depression in the orbital region. The zygoma was thin with a distinct process in the jugal bones. The upper canine was only moderately exceeding the height of the last corresponding premolar (in contrast with the conspicuously long canines of Hy. dolichodon ; see Fig. 3 . in Görföl et al. 2018). The first upper premolar was small and intruded. Lower molars were myotodont. The baculum was small (2.5 mm), broad in the middle and slightly constricted at both ends ( Fig. 14F ). The distal end was slightly groved but without any expansion. This corresponds well to the depiction of the baculum of Hy. affinis in Hill & Harrison (1987) and differs sharply from the baculum of Hy. dolichodon ( Fig. 5 in Görföl et al. 2018).

DNA: no biological material was obtained from this species.

Distribution and ecological notes: At present, two localities in Western Himalayas are known: Uttarakhand: Kumaon division and Mandal (1500 m) in Chamoli district ( Bates & Harrison 1997; present study). Both individuals were caught over a stream at the edge of an oak forest near human habitation. Hy. affinis is known to be an upland species with all records being within 1250–2530 m ( Görföl et al. 2018) and our present record also corroborates it. The echolocation call was recorded on release. We recorded narrowband (bandwidth=40.74 kHz) calls, ending at 25.89 kHz, and having a peak frequency of 30.51 kHz ( Table 6).

Taxonomic note: Hypsugo affinis is reportedly distributed in southern and northern parts of South Asia ( India, Nepal and Sri Lanka), southern China (Xizang, Yunnan, and Guangxi), and Southeast Asia ( Myanmar and Cambodia) ( Chheang et al. 2013; Srinivasulu & Srinivasulu, 2019a). However, Görföl et al. (2018) showed that recent records of this species from lowland Myanmar ( Bates et al. 2005) and Cambodia ( Chheang et al. 2013) actually represent the recently described species Hy. dolichodon . The type specimen of Hy. affinis was collected from Bhamo (ca. 24°15’N; 97°14’E) in Kachin State of northern Myanmar at an elevation of 1363 m ( Dobson 1871) and further records of the species all came from higher altitudes between 1250–2530 m ( Görföl et al. 2018). However, the skull of the type specimen of Hy. affinis in ZSI, Kolkata is not traceable, so final taxonomic assignation to either species is still problematic (op. cit.).

Figures

FIGURE 3: Neighbor-joining tree reconstruction of examined rhinolophids and hipposiderids COI sequences and based on the K2P matrix in Table S2. Branches are proportional to the number of mutational steps. Sequence names are composed of the first two letters of the genus, followed by the species name, the GenBank number (or field number for newly sequenced samples), and the region of origin. Samples from India are highlighted in bold face.

FIGURE 11. Portraits of some bat species recorded from the Western Himalayas during the present study.A) Ba. darjelingensis (released animal), B) Ep. pachyomus (ZSI–NERC V/M/ERS/420), C) Hy. affinis (ZSI–NERC V/M/ERS/638), D) Hy. savii (ZSI–NERC V/M/ERS/633), E) Mu. cf. aurata (released animal), F) Mu. cyclotis (ZSI–NERC V/M/ERS/425), G) Mu. huttonii (ZSI–NERC V/M/ERS/424), H) Mu. huttonii (released animal from Ansuya, Uttarakhand).

FIGURE 13. Dorsal, ventral, and lateral view of cranium and lateral and ventral view of mandible of A) Hy. affinis (ZSI–NERC V/M/ERS/638), and B) Hy. savii (ZSI–NERC V/M/ERS/633) from the Western Himalayas.

FIGURE 14. Dorsal (D), ventral (V) and lateral (L) profile of bacula of some bat species from the study area. A) Rh. macrotis (D, V, L, ZSI–NERC V/M/ERS/564), B) Rh. lepidus (D, V, L, ZSI–NERC V/M/ERS/449), C) Rh. nippon (D, V, ZSI–NERC V/M/ERS/402), D) My. himalaicus sp. nov. (D, ZSI–NERC V/M/ERS/653), E) Ny. leisleri (D, L, ZSI–NERC V/M/ERS/413), F) Hy. affinis (D, L, ZSI–NERC V/M/ERS/638), G) My. longipes (D, ZSI–NERC V/M/ERS/ 438), H) My. blythii (D, L, ZSI– NERC V/M/ERS/405), I) Mu. huttonii (D, V, ZSI–NERC V/M/ERS/ 443). Note, bacula B, D and I are partially damaged.