Journal of Threatened Taxa | www.threatenedtaxa.org | 26 September 2026 | 18(9): 29759–29763

ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print)

https://doi.org/10.11609/jott.10678.18.9.29759-29763

#10678 | Received 01 June 2026 | Final received 24 August 2026 | Finally accepted 05 September 2026

A century-long hiatus: rediscovery of Cadorna’s Pipistrelle Hypsugo cadornae (Chiroptera: Vespertilionidae) from India

Uttam Saikia ¹ & Gabor Csorba ²

¹ Zoological Survey of India, North Eastern Regional Centre, Risa Colony, Shillong, Meghalaya 793003, India.

² Department of Zoology, Hungarian Natural History Museum, Baross 13., Budapest, H–1088, Hungary.

¹ uttamzsi@gmail.com, ² csorba.gabor@nhmus.hu (corresponding author)

Editor: Bhargavi Srinivasulu, Zoo Outreach Organisation, Hyderabad, India. Date of publication: 26 September 2026 (online & print)

Citation: Saikia, U. & G. Csorba (2026). A century-long hiatus: rediscovery of Cadorna’s Pipistrelle Hypsugo cadornae (Chiroptera: Vespertilionidae) from India. Journal of Threatened Taxa 18(9): 29759–29763. https://doi.org/10.11609/jott.10678.18.9.29759-29763

Copyright: © Saikia & Csorba 2026. Creative Commons Attribution 4.0 International License. JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by providing adequate credit to the author(s) and the source of publication.

Funding: The funding for field surveys were provided by Zoological Survey of India as part of approved Annual Programme of Research. The work of GC was supported by the National Research, Development, and Innovation Office of Hungary (ADVANCED_25 152350).

Competing interests: The authors declare no competing interests.

Acknowledgements: US is grateful to the director, Zoological Survey of India, Kolkata and the officer-in-charge, ZSI, Shillong for institutional support and facilities. Survey permission from the chief wildlife warden, Government of Mizoram vide Memo B. 19060/1/2020-CWLW/ dated 28 August 2023 is highly appreciated.

Abstract: Cadorna’s Pipistrelle is a lesser-known vespertilionid bat, described from Darjeeling in the year 1916. Since its discovery, there has been no further record of this species from India. Based on two recently collected specimens from Mizoram State, the species has been reported from India after a gap of more than a century. A detailed description and morphometric measurements of the newly collected specimens are provided.

Keywords: Indo-Burma biodiversity hotspot, Mizoram, morphometrics, northeastern India, vespertilionid bat.

Based on a male specimen collected during the Mammal Survey of India organized by the Bombay Natural History Society, British zoologist Oldfield Thomas described Cadorna’s Pipistrelle Pipistrellus cadornae (Thomas, 1916). The type specimen was collected on 19 July 1915 by the veteran collector N.A. Baptista from Pashok, a village in the present Darjeeling District of West Bengal, India, at an elevation of 1,060 m. Since its original description more than a century ago, the species had not been recorded from India, resulting in considerable uncertainty regarding its current status in the country. During systematic surveys of bat fauna in the state of Mizoram, northeastern India, two male specimens of Hypsugo (as identified by their overall size, ear, and tragus shape) were collected; the present report documents their craniodental and bacular characteristics.

Materials and Methods

As part of a systematic assessment of the bat fauna of Mizoram State, field surveys were carried out at Sairep (22.9800^o N, 92.7491^o E, 1,450 m) in Lunglei District and Reiek (23.6922^o N, 92.6063^o E, 1,260 m) in Mamit District during October 2023 and March 2025, respectively. A two-bank harp trap (Austbat, Australia) and monofilament mist nets were employed for bat sampling. Both individuals were caught in the harp trap, euthanized, preserved in ethanol, and deposited in to the collection of Zoological Survey of India, Shillong under the registration nos. V/M/ERS/742 (Sairep specimen) and V/M/ERS/788 (Reiek specimen). The cranium and baculum of the specimens were extracted and prepared following established protocols (Topál 1958). Craniodental measurements of the vouchers were obtained with a digital calliper (Sylvac, Switzerland) accurate to the nearest 0.01 mm following standard methods. Unfortunately, due to possible issues with preservation, no genetic material could be extracted from any of the specimens.

The acronyms for measurements are: Tail length (TL); Ear length (E); Tragus length (TR); Hindfoot length excluding claw (HF); Forearm length (FA); Tibia length (TB); 3^rd Metacarpal length (3MT); 4^th Metacarpal length (4MT); 5^th Metacarpal length (5MT); Greatest length of skull including incisors (GTLi); Condylocanine length (CCL); Maxillary toothrow length (CM³); Width across third molars (M³-M³); Width across canines (C¹-C¹); Zygomatic breadth (ZW); Postorbital constriction (PoC); Breadth of braincase (BW); Mastoid breadth (MAB); Skull height (SKH); Length of mandible including incisors (MLi); Mandibular toothrow length (CM₃); Height of coronoid process (COH).

For comparison, the following museum specimens were examined. Museum acronyms are as follows – CBC:

Center for Biodiversity Conservation, Phnom Penh, Cambodia; CDZTU: Central Department of Zoology, Tribhuvan University, Kathmandu, Nepal; HNHM: Hungarian Natural History Museum, Budapest, Hungary; HZM: Harrison Institute (formerly Harrison Zoological Museum), Sevenoaks, UK; IEBR: Institute of Biology (formerly Institute of Ecological and Biological Resources), Hanoi, Vietnam; NHMUK: The Natural History Museum (formerly British Museum (Natural History)), London, UK; ROM: Royal Ontario Museum, Canada;

H. cadornae: CAMBODIA: CBC IS.010310.2; INDIA: NHMUK 16.3.25.6 (holotype); LAOS: ROM 106385; 110471, 110479, 118267, 118288, 118306, 118327, 118328; MYANMAR: NHMUK 1997.375, 50.466, 50.467, 50.480, 76.1266; NEPAL: CDZTU (no number); VIETNAM: HNHM 2014.3.2; HZM 1.30538, 2.32164, 3.32165, 4.32166; IEBR 2556, 3266, 3269, PM05; ROM 106200, 106201, 106202, 107650, 107653.

Results

Descriptions of the specimens: The forearm length of the newly recorded specimens are 35.0 and 35.7 mm. The dorsal fur is chocolate brown with a slight glossy sheen, while the ventral fur is a lighter brown (Image 1). The bases of both dorsal and ventral hairs are dark brown. The wing and tail membranes are dark brown. The muzzle bears scattered hairs and swollen glands. The ears are broad; the distal margin is straight and rises to form a broadly rounded tip, whereas the proximal margin descends straight for approximately two-thirds of its length before curving inward to join the ear base. Five horizontal ridges are present across the distal half of the pinna. The tragus is short, wide, and curves inward.

Among the wing elements, the third metacarpal is the longest, followed by the fourth and fifth metacarpals (Table 1). The thumb bears a prominent oval callosity. The wing membrane attaches at the base of the toes. The calcar runs for around two thirds along the edge of the interfemoral membrane and has a longish lobe. The interfemoral membrane attaches to the feet at the tibio-metatarsal joint (the origin point of calcar). The tail is enclosed within the interfemoral membrane except for the terminal tip. The testes of the Sairep specimen collected in October 2023 were swollen. In both individuals, the penis is thick, hirsute, and lacks any distinct modifications.

The cranium, in lateral view, exhibits an almost straight dorsal profile, except for a slightly elevated midsection (Image 2). The sagittal and lambdoid crests are moderately developed. In dorsal view, the braincase appears globose, the zygomatic arches are slightly flared outward, and the narial emargination is V-shaped. The first upper incisor is bicuspid and approximately equal in height to the second incisor. A distinct diastema is present between the second incisor and the canine. The canine is robust, unicuspid, and approximately twice the height of the second premolar. In the upper toothrow the first premolar is minute and completely displaced from the toothrow, resulting in direct contact between the canine and second premolar; the first and second molars possess nearly equal crown areas. The third molar is reduced, parastyle, and protocone are absent. The lower canine is weak, and the first lower incisor reaches about two thirds the height of the canine. Second lower premolar is higher than the first but does not attain the height of the lower canine. The first two lower molars possess a myotodont cusp structure. The third molar is slightly reduced than the first two in surface area.

The baculum measures 2.35 mm in both specimens. In dorsal view, the baculum has a bulbous base, from which the shaft gradually widens to reach its maximum width at approximately two-thirds of its total length. Distal to this point, the shaft tapers slightly and terminates in a broad, rounded tip; in lateral view, the shaft curves anteriorly (Image 2F). It possesses a deep ventral groove.

The overall size, ear and tragus shape, combined with the bacular traits and myotodont dental characteristics, undoubtedly identify the two specimens as Hypsugo; within the genus, as defined by the FA length (below 37 mm), and the minute, labially fully intruded P2, they evidently represent H. cadornae.

Ecological notes: At Sairep Village, the individual was caught in the harp trap set across a forest trail. The sampling area was situated at a hilltop surrounded by tropical evergreen forest and bamboo clumps. At Reiek, the specimen was caught in the harp trap set across a dry stream bed surrounded by tropical semi evergreen forest. Both the locations are in the vicinity of human habitations indicating its adaptation to human proximity. Although all the Indian records (Image 3) thus far are from mid elevation ranges (1,060–1,450 m), in other parts of the range, it was recorded from lowland forests and near human periphery (Bates et al. 2005; Xie et al. 2021) indicating broad ecological adaptations. Presence of distinct thumb pads in the specimens may also indicate roosting habits in smooth surfaces like bamboo internodes etc. Although no echolocation calls could be recorded, the reported maximum echolocation call frequency of 65.60 ± 4.89 kHz in China is suitable for hunting hard bodied insects like beetles or bugs (Xie et al. 2021).

Discussion

Hypsugo cadornae is a widely distributed vespertilionid bat in southeastern Asia but confirmed locality records across the region remain sporadic (Bates et al. 2019). Interestingly, apart from its type locality, the species has not been documented elsewhere in India. This apparent rarity is likely attributable to the lack of extensive field surveys and rigorous taxonomic investigations, a pattern that broadly characterizes bat research in India. However, recent records from two localities in Mizoram suggest its continued presence in suitable habitats of northeastern India. Although classified as ‘Least Concern’ on the IUCN Red List (Bates et al. 2019), the species remains poorly studied, and the absence of population data highlights the need for further surveys and conservation-focused research across its range.

Table 1. Comparative morphometric details (in mm) of Hypsugo cadornae from Mizoram, India and from other parts of its distribution range including the type specimen (refer to comparative materials).

Parameter	Sairep V/M/ERS/742	Reiek V/M/ERS/788	Holotype	Specimens from SE Asia
Wt (g)	6.0	7.0	-	-
TL	38.0		-	-
E	12.0	13.9	-	-
TR	4.8	5.8	-	-
FA	35,0	35.7	-	35.4 ± 1.20 33.2–37.0 (19)
TB	15.7	15.8	-	15.2 ± 0.97 13.1–16.4 (13)
HF	5.8	6.7	-	6.1 ± 0.42 5.2–6.9 (17)
3MT	34.6		-	-
4MT	32.5		-	-
5MT	31.2		-	-
GTLi	13.70	14.56	-	13.71 ± 0.28 13.40–14.11 (23)
CCL	12.70	13.53	12.80	12.85 ± 0.23 12.44–13.32 (25)
ZB	8.73	9.73		8.73 ± 0.23 8.49–9.10 (17)
BW	6.47	7.21	7.09	6.80 ± 0.16 6.50–7.11 (23)
MAW	7.00	7.92	7.74	7.68 ± 0.22 7.09–8.01 (23)
POC	3.80		3.97	3.69 ± 0.13 3.45–3.93 (26)
SKH	5.40		5.11	4.90 ± 0.16 4.52–5.15 (24)
C^1C^1	4.55	4.88	4.76	4.61 ± 0.15 4.30–4.86 (26)
M^3M^3	6.14	6.38	6.28	5.91 ± 0.19 5.61–6.28 (25)
CM^3	4.52	4.94	4.91	4.70 ± 0.10 4.56–4.88 (26)
MLi	9.90		9.75	9.71 ± 0.19 9.42–10.13 (26)
CM3	4.93	5.53	-	5.03 ± 0.11 4.84–5.16 (26)
COH	3.07		2.81	2.71 ± 0.09 2.53–2.87 (25)
Baculum length	2.35	2.35	-	-

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References

Bates, P.J.J. et al. (2005). A review of the genera Myotis, Ia, Pipistrellus, Hypsugo, and Arielulus (Chiroptera: Vespertilionidae) from Myanmar (Burma), including three species new to the country. Acta Chiropterologica 7: 205–236. https://doi.org/10.3161/150811005775162614

Bates, P.J.J. et al. (2019). Hypsugo cadornae. IUCN Red List of Threatened Species. e.T17331A22130442. https://doi.org/10.2305/IUCN.UK.2019-3.RLTS.T17331A22130442.en. Retrieved on 11.v.2026

Thomas O. (1916). Scientific results from the Mammal Survey. XII. Journal of Bombay Natural History Society 24: 404–430.

Topál G. (1958). Morphological studies on the os penis of bats in the Carpathian basin. Annales Historico-Naturales Musei Nationalis Hungarici L(IX): 331–342.

Xie, H.W. et al. (2021). First records of Hypsugo cadornae (Chiroptera: Vespertilionidae) in China. Mammalia 85(2): 189–192. https://doi.org/10.1515/mammalia-2020-0029