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ОглавлениеEpomophorus labiatus (Temminck 1837)
Little epauletted fruit bat Least Concern
Description: Epomophorus labiatus is a medium-sized bat with a mass of around 45–55 g; it is the smallest representative of its genus. The pelage is light sandy-brown. The underparts are slightly paler than the upper parts. The wings are light brown and sparsely covered in hair. Adult males are larger than females, and may be distinguished by a broader muzzle with a folded upper lip and the presence of shoulder epaulettes. These epaulettes are pockets containing long, white fur that can be erected to display prominent white shoulder patches. At rest, these patches disappear as the fur is retracted into the pocket. The ears have a patch of white fur at their base. The muzzle is dog-like.
For a fruit bat, the skull is small and relatively delicate with weak zygomatic arches. In lateral profile, the rostrum and interorbital region are flat, while the parietal region is rounded and deflected downwards. The sagittal crest is absent, while the lambdoid crest is weak. There are six narrow palatal ridges present, two beyond the last molar. Only the fifth and sixth ridges are divided by a narrow groove. The dental formula is 2121/2132 = 28.
Key identification features: The combination of white patches at the base of the ears and shoulder epaulettes (males) separates Epomophorus, Epomops and Micropteropus from other fruit bats. The palatal ridges of Epomops and Micropteropus are very different from those of Epomophorus; in the latter there are six narrow ridges (five thick ridges in Micropteropus and Epomops). Adult E. labiatus can be distinguished from the much larger sympatric E. wahlbergi and E. crypturus by size (FA < 70 mm; in E. wahlbergi and E. crypturus FA > 75 mm). Epomophorus labiatus overlaps in size with E. grandis, but in the latter the second to sixth palatal ridges are divided (second to fourth ridges not divided in E. labiatus). Epomophorus anselli is larger (male E. anselli FA > 70 mm; male E. labiatus minor FA < 70 mm).
Echolocation call: This bat does not echolocate.
Distribution, habitat and roosting: Epomophorus labiatus is widespread in Malawi and northeast Zambia. It has also been collected from northwestern Mozambique along the shores of Lake Malawi (Monadjem et al. 2010a). It may have been overlooked in northern and central Mozambique where it might be more widespread than the current map suggests. The type specimen for labiatus is from the Nile Province of Sudan, while that for minor is Zanzibar, Tanzania (BM 79.9.12.4, Lectotype).
Considering the restricted distribution of this taxon, it is relatively well represented in museums, with over 30 records examined for this book.
In southern Africa, it has been recorded roosting in a banana tree (Lawrence and Loveridge in Happold et al. 1987) and a disused tourist hut (Ansell 1967). In Mozambique, it was netted in a small banana plantation (A. Monadjem, personal observation), suggesting that it was roosting in the banana trees. This taxon is associated with fruiting trees in woodland savanna (Happold et al. 1987).
| External and cranial measurements (mm) and mass (g) for Epomophorus labiatus, males and females presented separately | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean | Min | Max | SD | N | Mean | Min | Max | SD | N | ||
| Males | Females | ||||||||||
| Mass 1 | 53.5 | 48.0 | 63.5 | 6.30 | 5 | Mass 1 | 40.5 | 32.5 | 51.0 | 5.80 | 9 |
| FA 1 | 63.7 | 61.0 | 68.0 | 2.80 | 5 | FA 1 | 60.5 | 58.0 | 63.5 | 1.70 | 9 |
| Total 1 | 110.7 | 105 | 115 | - | 4 | Total 1 | 97.2 | 90 | 103 | 5.40 | 5 |
| Tail 1 | 2.0 | 0 | 5 | - | 4 | Tail 1 | 2.4 | 0 | 5 | 2.50 | 5 |
| Tibia 1 | 27.2 | 26.0 | 29.0 | 1.10 | 5 | Tibia 1 | 25.7 | 24.0 | 27.5 | 1.30 | 7 |
| Ear 1 | 19.6 | 18 | 21 | 1.10 | 5 | Ear 1 | 17.8 | 17 | 19 | 0.90 | 7 |
| CI 2 | 34.3 | 30.0 | 36.0 | 2.57 | 5 | CI 2 | 31.5 | 29.1 | 33.7 | 2.17 | 5 |
1 Happold et al. (1987)2 Specimens measured by the authors
Figure 55. Skull and teeth of Epomophorus labiatus: (a) dorsal view, (b) ventral view, (c) lateral view, and (d) lateral view of mandible (DM 8644).
Figure 56. Adult Epomophorus labiatus, showing the small size of the bat (DM 8644, © A. Monadjem).
Extralimital: Epomophorus labiatus occurs widely in East Africa west to Nigeria, including Tanzania, Burundi, Rwanda, Uganda, Kenya, Somalia, Sudan, Ethiopia, Chad, Congo, and DRC. The taxon minor, however, is restricted to East Africa, occurring in Kenya, Tanzania, Ethiopia, Sudan and DRC.
Foraging ecology: There is no information on the diet or foraging behaviour of Epomophorus labiatus in southern Africa, but elsewhere it feeds on the following plants: Mangifera indica, Kigelia aethiopica, K. pinnata, Ficus natalensis, F. vallis-choudae, and Irvingia smithii (Fujita and Tuttle 1991).
Reproduction: In Zambia, a pregnant female with foetus was collected on 16 November (Ansell 1967); in Malawi, juveniles have been taken in January, March, April, May, October and November (Bergmans and van Strien 2004), suggesting that Epomophorus labiatus may breed throughout the year.
SYSTEMATIC NOTES
1837.Pteropus labiatus Temminck, Monographies de mammalogie, ou description de quelques genres de mammifères, dont les espèces ont été observées dans les différens musées de l’Europe. II (2): 49–140. Van de Hoek, Leiden and Dufour and d’Ocagne, Paris.
1880.Epomophorus minor Dobson, Proc. Zool. Soc. Lond., 1879, IV: 715. Zanzibar, Tanzania.
The names reii Aellen 1950 and doriae Matschie 1899 are synonyms. There is confusion regarding the taxonomic relationships within the small-sized Epomophorus bats – the labiatus/minor/minimus group. Here, we retain minor within labiatus. Bergmans (1988) recognised E. minor as a valid species with a predominantly East African distribution ranging from Malawi and Zambia north to Tanzania, Kenya and Ethiopia, with several possible records from southern DRC (van Cakenberghe et al. 2017). The taxon E. minimus has also been confused with E. labiatus and a single possible record exists for southern DRC (van Cakenberghe et al. 2017). Epomophorus labiatus, in contrast, has the core of its distribution centred around Lake Victoria, extending north into Ethiopia and Sudan and south into northwestern Tanzania. An isolated population from Malawi (Bergmans 1988), which was originally identified as anurus (Heuglin 1864), is now synonymised with labiatus, while another Malawi population was recently elevated to specific rank as E. anselli (Bergmans and van Strien 2004). Currently, labiatus, minor and minimus can only be distinguished based on slight differences in size. Molecular studies, not yet conducted on this group, are long overdue and may finally resolve the relationship between these taxa.
1 Happold et al. (1987)
2 Specimens measured by the authors
