Comments on Welwitsch's mouse-eared bat (Myotis welwitschii) with the first record from Cameroon

Comments on Welwitsch's mouse-eared bat (Myotis welwitschii) with the first record from Cameroon

ARTICLE IN PRESS www.elsevier.de/mambio Short communication Comments on Welwitsch’s mouse-eared bat (Myotis welwitschii) with the first record from...

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Comments on Welwitsch’s mouse-eared bat (Myotis welwitschii) with the first record from Cameroon By O. Sedla´cˇek, D. Horˇa´k, J. Riegert, J. Reif and I. Hora´cˇek Department of Ecology, Charles University, Prague; Department of Zoology, Charles University, Prague; Department of Zoology, University of South Bohemia, Cˇeske´ Budeˇjovice; and Center for Theoretical Study, Charles University, Prague, Czech Republic Receipt of Ms. 1.2.2005 Acceptance of Ms. 19.11.2005

Key words: Myotis welwitschii, distribution, new record, Cameroon

Welwitch’s mouse-eared bat, Myotis welwitschii (Gray, 1866) is a large-sized representative of the genus Myotis, which ranks among the rarest African bats. Its taxonomical and distributional status has remained enigmatic for a long time. On 15 December 2003, we captured a male individual of the species about 5 km eastern from Big Babanki village in the Bamenda Highlands, NW Province, Cameroon (GPS position: N061050 2700 ; E101180 900 ; 2203 m a.s.l.). This is the first record of M. welwitschii from Cameroon and the second one from West Africa. The record is quite distant from the nearest known localities in Guinea, Angola and eastern Congo (see Fahr and Ebigbo 2003 for review) and thus it improves the current knowledge of the species’ distribution in an essential way. The individual was found on daytime when roosted freely at trunk of Vernonia sp. (family Asteraceae) about 1 m above ground. The locality is situated in the centre of the mountain range with the highest summits reaching 2000–3000 m a.s.l. The vegetation cover consists of mosaic of montane forest patches, shrubby corridors, grasslands and vegetable plantations. The measurements of the specimen (adult male, testes 4.5  3.0 mm in retreat, cauda epididymys quite long) were

as follows: FA 61.7 mm, HB 60.0, tail 58.0, A 20.0, T 8.5, hind foot 13.7, tibia 26.8 mm, weight 6.3 g, LCr 20.6, Cb 20.0, Zyg 13.6, IO 4.8, InfO 6.0, BB 9.2, MastB 10.4, HB 6.6, IM3/ 9.7, CM3/ 8.3, P4M3/ 5.9, M1M3/ 4.8, CC 5.5, P4P4 6.6, M3M3 8.5, Md 16.2, IM/3 10.3, CM/3 8.9, P4M/3 6.5, M1M/3 5.5, CrH 5.2. In most measurements the specimen slightly exceeds the variation range reported for this species (Kock 1967; Taylor 1991; Ratcliffe 2002; Fahr and Ebigbo 2003). The specimen is deposited in the collections of Department of Zoology, Charles University Prague. Likewise in many animal taxa living in tropical regions, the distribution of M. welwitschii is to the considerable degree unknown or based on rather casual records. Until now, no breeding colony was found, no data on reproduction or roosting ecology are available except the information based on individual specimens. Considering them, the species is reported to roost solitarily in canopy, low bushes or in houses (Ratcliffe 2002) without any preference of underground roosts (Taylor 1991). Its extreme rarity in all regions from which it was reported is stressed as a typical character of the species (Rautenbach 1997). Until 2002, the known range of the species was restricted to southern and

1616-5047/$ - see front matter r 2005 Deutsche Gesellschaft fu¨r Sa¨ugetierkunde. Published by Elsevier GmbH. All rights reserved. doi:10.1016/j.mambio.2005.11.004 Mamm. biol. 71 (2006) 2  120–123

ARTICLE IN PRESS Welwitsch’s mouse-eared bat from Cameroon

eastern parts of Africa (Ratcliffe 2002). Kock (1967) reported it from 18 localities situated in 11 nowadays countries. The most recent review summarizes 61 records from 14 countries – Angola, Burundi, Congo, Ethiopia, Kenya, Malawi, Mozambique, Rwanda, South Africa, Sudan, Tanzania, Uganda, Zambia and Zimbabwe (Fahr and Ebigbo 2003). The situation changed in December 2002, when three individuals of this species were captured in Simandou Range, Guinea, West Africa (Fahr and Ebigbo 2003), i.e. about 3400 km far from the nearest localities of its known range. Fahr and Ebigbo (2003) supplemented their report with a detailed list of all distributional records and discussed them in the biogeographical context. They demonstrated that most records are centred in high mountains (55–2311 m a.s.l., with a median of 1209 m). This supports the previous conclusions made by Koopman (1983) who termed such pattern of distribution as ‘‘paramontane’’. The present record comes from a mountain region, too. In spite the numerous rock niches and caves at the locality, the specimen roosted unconcealed in vegetation, which corroborates published data (Taylor 1991). The geographic position of our finding suggests that the range of the species covers more regions of Sub-Saharan Africa than was previously thought. The misidentification of M. welwitschii is improbable because of its remarkable colouration pattern. The pelage is generally trichromatic and reddish brown at back as in M. emarginatus and M. tricolor. However, dichromatic wing membranes distinguish M. welwitschii from these two species: membranes are bright orange along body, legs, forearm and fingers (irregularly dotted with black spots) and dark brown at distal parts. Two Eastern Asiatic species, M. formosus and Kerivoula picta, share exactly the same unique pattern of wing colouration. Myotis welwitschii and M. formosus exhibit the other close similarities in many cranial, dental and external characters (as confirmed by direct comparisons with the specimens in Natural History Museum, London and Senckenberg Nat-hist. Museum, Frankfurt a. M.). Dobson (1878) first redescribed M. welwitschii in details based on the type specimen from

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Angola, the only one available at that time. He has already stressed the considerable similarity between M. welwitschii and M. formosus though he apparently hesitated to believe in actual proximity of both the species. Myotis formosus was traditionally classified in a separate subgenus Chrysopteron Jentink, 1910 (Tate 1942; Ellerman and Morrison-Scott 1951; Corbet and Hill 1992). Findley (1972), who provided the first modern reclassification of the genus based on phenetic analyses, arranged both M. welwitschii and M. formosus into a separate species group within the subgenus Myotis. Koopman (1994) adopted that view and called formally the clade ‘‘formosus-group’’. The modern re-examination of the genus Myotis based on mtDNA sequence analysis (Ruedi and Mayer 2001) demonstrated close relations between M. welwitschii and M. emarginatus, and a distinct position of that clade near to the root of divergence of the genus. The most recent contributions to the molecular phylogeny of the genus (Bickham et al. 2004; Stadelmann et al. 2004) that brought the first molecular data on M. formosus, demonstrated independently that M. welwitschii and M. formosus are closely related sister taxa. These data indicate that the numerous similarities between the two species (e.g. extremely narrow tragic, tricoloured hairs on back and similar colouration of membranes) is the heritage of their common ancestry. Moreover, there are some striking similarities between the two species in the areographic patterns of their distribution. Both M. welwitschii and M. formosus seem to be rare species in any part of their ranges, and, at the same time, their ranges are extremely large (Fig. 1). The records of M. welwitschii are dispersed over nearly whole Ethiopian region, those of M. formosus cover major part of the Oriental region (Fig. 1, Corbet and Hill 1992). Similarly as in M. welwitschii, the total number of records of M. formosus is quite low (about 50) and most of them come from the mountain regions (Corbet and Hill 1992; Bates and Harrison 1997; Zhang 1997). In the majority of cases, the records of M. formosus are casual captures of single individuals roosting in foliage. The records of small

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O. Sedla´cˇek et al.

Fig. 1. Distributional records of Myotis welwitschii (dots) and Myotis formosus (squares) based on published data, including the recent record from Cameroon (indicated by arrow).

colonies roosting in protected sites are limited to Taiwan (Shen and Lee 2000). In this respect, similarity between M. welwitschii and M. formosus is indeed surprising. Possibly, the respective distributional and behavioural specificities may represent one of the apomorphies of the clade. Last but not least, it should be stressed that these specificities are indeed quite unique. There is no other clade of bats, being composed of two closely related species, which colonized as large Eupaleotropic range and exhibit the vicariance pattern conforming exactly to the two major units of the Paleotropic region. What else in biology and distributional dynamics of these bats is behind the striking specificities of that clade is undoubtedly worth of a focused interest.

Acknowledgement We wish to thank Michael Bartosˇ , Jakub Brom, Da´sˇ a Bystrˇ icka´, Za´boj Hra´zsky´, Sˇteˇpa´n Janecˇek and Michael Pesˇ ata, who helped us in the field. We are grateful to Bamenda Highlands and Kilum-Ijim Forest Projects, especially to Michael Boboh Vabi, for enabling us the research in Bamenda Highlands. The study was performed with kind permission of NdawaraBelo ranch. We wish to thank Grant Agency of the Czech Republic (GACR 206/03/H034) and Ministry of Education of the Czech Republic (MSM 6007665801) for financial support.

References Bates, P. J. J.; Harrison, D. L. (1997): Bats of the Indian Subcontinent. Sevenoaks: Harrison Zoological Museum. Bickham, J. W.; Patton, J. C.; Schlitzter, D. A.; Rautenbach, I. L.; Honeycutt, R. L. (2004): Molecular phylogenies, karyotype diversity, and partition of the genus Myotis (Chiroptera: Vespertilionidae). Mol. Phylogenet. Evol. 13, 333–338.

Corbet, G. B.; Hill, J. E. (1992): The Mammals of the Indomalayan Region: A Systematic Review. Oxford: Oxford University Press. Dobson, G. E. (1878): Catalogue of the Chiroptera in the Collection of the British Museum. London: Trustees of British Museum. Ellerman, J. R.; Morrison-Scott, T. C. S. (1951): Checklist of Palearctic and Indian Mammals 1758 to 1946. London: British Museum (NH).

ARTICLE IN PRESS Welwitsch’s mouse-eared bat from Cameroon

Fahr, J.; Ebigbo, N. M. (2003): A conservation assessment of the bats of the Simandou Range, Guinea, with the first record of Myotis welwitschii (Gray, 1866) from West Africa. Acta Chiropterol. 5, 125–141. Findley, J. S. (1972): Phenetic relationship among bats of the genus Myotis. Syst. Zool. 21, 31–52. Kock, D. (1967): Ein Neunachweis von Myotis welwitschii und der Status von Myotis venustus (Mammalia, Chiroptera). Senck. Biol. 48, 319–325. Koopman, K. F. (1983): Two general problems involved in systematics and zoogeography of bats. In: Advances in Herpetology and Evolutionary Biology. Essays in honour of Ernwest E. Williams, Ed. by A. G. J. Rhodin, K. Miyata. Cambridge: Museum of Comparative Zoology, Pp. 412–415. Koopman, K. F. (1994): Chiroptera: Systematics. Handbuch der Zoologie, Vol. 8, Part 60. Berlin: Walter de Gruyter. Rautenbach, N. (1997): Myotis welwitschii. In: The Complete Book of Southern African Mammals, Ed. by G. Mills, L. Hes. Kapstadt: Struik Publishers. Ratcliffe, J. M. (2002): Myotis welwitschii. Mammalian Species 701, 1–3. Ruedi, M.; Mayer, F. (2001): Molecular systematics of bats of the genus Myotis (Vespertilionidae) suggests deterministic ecomorphological

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convergences. Mol. Phylogenet. Evol. 21, 436–448. Shen, H. P.; Lee, L. L. (2000): Mother–young interactions in a maternity colony of Myotis formosus. J. Mammalogy 81, 726–733. Stadelmann, B.; Jacobs, D. S.; Schoeman, C.; Ruedi, M. (2004): Phylogeny of African Myotis bats (Chiroptera, Vespertilionidae) inferred from cytochrome B sequences. Acta Chiropterol. 6, 177–192. Taylor, P. J. (1991): First record of Welwitsch’s hairy bat (Myotis welwitschii) from Natal. Durban Mus. Novitates 16, 35–36. Zhang, Y. (1997): Distribution of Mammalian Species in China. Beijing: China Forestry Publishers House.

Authors’ addresses: Ondrˇ ej Sedla´cˇek, Department of Ecology, Faculty of Science, Charles University, Vinicˇna´ 7, CZ-128 44 Praha 2, Czech Republic (e-mail: [email protected].) Ivan Hora´cˇek, David Horˇ a´k, Jirˇ ı´ Reif, Department of Zoology, Faculty of Science, Charles University, Vinicˇna´ 7, CZ-128 44 Praha 2, Czech Republic Jan Riegert, Department of Zoology, Faculty of Biological Sciences, University of South Bohemia, Branisˇ ovska´ 31, CZ-370 05 Cˇeske´ Budeˇjovice, Czech Republic