Bats of Southern and Central Africa. Ara Monadjem
Читать онлайн книгу.
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
Epomophorus dobsonii Bocage 1889
Dobson’s epauletted fruit bat Least Concern
Description: Epomophorus dobsonii is a large bat with a mass over 100 g in adult males. The pelage is greyish-brown. The wings are dark brown. 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 (18 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. Adult males also have dark grey-brown throats, while females have greyish throats. The ears have a patch of white fur at their base. The muzzle is dog-like and broader than that of most similar-sized Epomophorus species.
The skull is robust with sturdy zygomatic arches. In lateral profile, the rostrum and interorbital region are rather flat, while the parietal region is deflected downwards. From above, the rostrum is broad. There are five thick palatal ridges present, two beyond the last molar. The first three ridges are continuous while the last two are divided, giving the impression of four triangles behind the last molar. 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 Epomops and Epomophorus from other large fruit bats. Palatal ridges immediately separate these two genera, with Epomophorus exhibiting six narrow ridges (five thick ridges in E. dobsonii). Epomophorus dobsonii is easily distinguished from E. franqueti by the number of post-dental palatal ridges (two in E. dobsonii, five in E. franqueti).
Echolocation call: This bat does not echolocate.
Distribution, habitat and roosting: Epomophorus dobsonii is widespread in the northern parts of the region, where it has been recorded from central Angola and northern Botswana (Smithers 1971), east through Zambia, southern DRC and northern Malawi. It may have been overlooked over much of eastern Angola, the Caprivi Strip of Namibia, and the extreme northwest of Mozambique. The type specimen is from Quindumbo, Angola. This specimen (housed in the Museu Bocage) was destroyed in the tragic fire of 1978. Bergmans (1989) selected a new type specimen from Chitau approximately 250 km to the southwest of Quindumbo (AMNH 88068, Neotype).
This species is poorly represented in museums, with only 27 records examined for this book.
| External and cranial measurements (mm) and mass (g) for Epomophorus dobsonii, males and females presented separately | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean | Min | Max | SD | N | Mean | Min | Max | SD | N | ||
| Males |
Females
|