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ОглавлениеEpomophorus crypturus Peters 1852
Peters’s epauletted fruit bat Least Concern
Description: Epomophorus crypturus is a large bat with a mass of about 100 g. 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 much 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 (9 mm in length) 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 and narrower than that of the similar E. wahlbergi (Taylor and Monadjem 2008).
The skull is robust with sturdy zygomatic arches. Mature males have larger skulls (greatest length > 52 mm) than females (< 52 mm). In lateral profile, the entire cranium is dorsoventrally flattened and only very slightly bowed; the rostrum slopes gradually downwards anteriorly and the braincase is very slightly deflected downward posteriorly. The maxilla is distinctly narrower than in E. wahlbergi (Taylor and Monadjem 2008). The sagittal crest is low, but usually clearly visible. The lambdoid crest is fairly well developed. There are six narrow palatal ridges present, two beyond the last molar. The fourth palatal ridge is midway between the third and the fifth ridges. 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 and Epomops from other fruit bats. Palatal ridges of Epomops are very different from those of Epomophorus; in the latter there are six narrow ridges. Adult E. crypturus can be distinguished from sympatric E. wahlbergi by the presence of two post-dental palatal ridges (only one in E. wahlbergi) and narrower muzzle (in E. crypturus, width of maxilla at labial posterior edges of the upper M3 < 13 mm, < 14 mm in adult females and males, respectively; in E. wahlbergi > 13 mm, > 14 mm in females and males, respectively) (Taylor and Monadjem 2008). Epomophorus crypturus and E. angolensis can be separated by the pattern of palatal ridges whereby the fourth palatal ridge is midway between the third and fifth ridges in E. crypturus.
Echolocation call: This bat does not echolocate.
Distribution, habitat and roosting: Epomophorus crypturus is widespread and abundant in the eastern parts of the region, where it has been recorded from northern KwaZulu-Natal and Eswatini, through the Kruger National Park to Zimbabwe, northern Botswana, Zambia, Malawi, extreme southern DRC and northern Mozambique. It appears to be absent from coastal forest in southern Mozambique, and there are only two records for eastern Angola. It is possibly widespread in eastern Angola, where it may have been overlooked. The type specimen is from Tete, Mozambique (ZMB 10080, Lectotype).
| External and cranial measurements (mm) and mass (g) for Epomophorus crypturus, males and females presented separately | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean | Min | Max | SD | N | Mean | Min | Max | SD | N | ||
| Males | Females | ||||||||||
| Mass 1 | 104.5 | 80.0 | 140.0 | 12 | Mass 1 | 75.5 | 64.0 | 88.0 | 12 | ||
| FA 2 | 84.5 | 80.0 | 88.4 | 51 | FA 2 | 79.0 | 75.0 | 83.2 | 40 | ||
| Total 3 | 147.0 | 126 | 168 | 14.30 | 14 | Total 3 | 129.0 | 106 | 148 | 12.20 | 16 |
| Tail 3 | 0 | 8 | Tail 3 | 0 | 12 | ||||||
| Tibia | - | - | - | - | - | Tibia | - | - | - | - | - |
| Ear 3 | 24.8 | 19 | 28 | 2.50 | 14 | Ear 3 | 24 | 21 | 27 | 1.77 | 16 |
| CI 3 | 51.5 | 44.7 | 55.1 | 2.70 | 18 | CI 3 | 42.3 | 37.7 | 46.0 | 2.49 | 18 |
1 From Skinner and Chimimba (2005)2 Bergmans (1988)3 Specimens measured by the authors
Figure 51. Skull and teeth of Epomophorus crypturus: (a) dorsal view, (b) ventral view, (c) lateral view, and (d) lateral view of mandible (DM 8035).
This species is well represented in museums, with over 160 records examined for this book.
Epomophorus crypturus roosts singly or in small groups in the dense foliage of a large, leafy tree and may travel several kilometres each night to reach fruiting trees. It is associated with forest and forest-edge habitats, particularly riparian forests that extensively incise savannas in the eastern part of the region. However, it appears to prefer drier conditions than E. wahlbergi, hence its absence from coastal forests in Mozambique and South Africa. It may occur sympatrically with E. wahlbergi, but usually one or the other species is numerically dominant.
Extralimital: Epomophorus crypturus is a near-endemic to southern Africa, occurring marginally outside of it in the extreme south of Tanzania.
Foraging ecology: Epomophorus crypturus feeds on a wide variety of fruit and flowers, with figs apparently being favoured (Smithers 1983). Fruits eaten include Ficus spp., Sclerocarya birrea, Parinari curatellifolia, Pseudolachnostylis maprouneifolia, Uapaca kirkiana, Berchemia discolor, Mimusops zeyheri and Rauvolfia caffra (Smithers 1983). Fruits are typically carried to feeding sites close to where they were plucked from; these feeding roosts are often on a large branch from which the bats can hang. They are wasteful feeders, discarding hard skins, seeds, pips and mouthfuls of chewed pulp onto the ground below (Smithers 1983). In Zimbabwe, telemetry studies showed that they began foraging less than 45 minutes after dark, visiting the same fruiting tree on two subsequent nights (Thomas and Fenton 1978). In Kruger National Park, tagged bats spent > 90% of their activity time in riparian forest, and foraging over an area of 20–52 hectares (Bonaccorso et al. 2014).
Reproduction: In Zimbabwe, pregnant females were recorded throughout most of the year, with a peak in the presence of juveniles in September, suggesting that births predominantly occur at the beginning of the wet season (Smithers and Wilson 1979). One or rarely two young are born.
Figure 52. Epomophorus crypturus: (a) portrait showing white ear tufts, and (b) individual in flight carrying fruit in its mouth (a: © A. Monadjem; b: © Merlin D. Tuttle, Bat Conservation International, www.batcon.org).
SYSTEMATIC NOTES
1852.Epomophorus crypturus Peters, Reise nach Mossambique, Zoologie 1, Säugethiere: 26. Tete, Zambezi, western Mozambique.
Epomophorus crypturus has traditionally been treated as a subspecies of E. gambianus. Bergmans (1988) recognised three subspecies – gambianus (Olgiby 1835), pousarguesi Trouessart 1904 and crypturus – and showed that parvus Ansell 1960 from Zambia did not differ cranially from crypturus. However, crypturus is widely separated from the other two subspecies, occurs in a different habitat and may have some cranial differences (Bergmans 1988). For this reason we prefer to treat crypturus (incorporating parvus) as a full species.
The diploid number in E. crypturus is 2n = 35 (male), 36 (female) and FN = 68 (Peterson and Nagorsen 1975).
1 From Skinner and Chimimba (2005)
2 Bergmans (1988)
3 Specimens measured by the authors
