Nycteris thebaica, E. Geoffroy, 1818

Don E. Wilson & Russell A. Mittermeier, 2019, Nycteridae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 374-386 : 386

15.

Egyptian Slitfaced Bat

Nycteris thebaica

French: Nyctére de Thébaide / German: Agyptische Schlitznase / Spanish: Nicterio egipcio

Other common names: Cape Long-eared Bat, Cape Slit-faced Bat, Common Slit-faced Bat, Geoffroy's Nycteris

Taxonomy. Nycteris thebaicus [sic] E. Geoffroy Saint-Hilaire, 1818 ,

Thebes, Egypt.

Nycteris thebaica belongs to the thebaica group. Seven subspecies ( thebaica , angolensis, brockmani, capensis, damarensis, labiata, and najdiya) have been named, but their taxonomic validity needs revision. Monotypic.

Distribution. Widely distributed throughout much of sub-Saharan Africa, from Senegal in W to Ethiopia and Somalia in E, S to South Africa (but absent from most of Congo Basin), and N along Nile River through Sudan to Egypt and across to Israel and Jordan; there is an isolated population in Morocco and another one on W coast of Saudi Arabia along Red Sea S to Yemen.

Descriptive notes. Head—body 40-56 mm, tail 40-63 mm, ear 26-37 mm, hindfoot 8-14 mm, forearm 34-52 mm; weight 6-16 g. The Egyptian Slitfaced Bat is small, with short rounded wings. Longitudinal cleft runs along top of muzzle, covering noseleaves. Fur is long and fluffy pale gray, reddish brown to dark brown dorsally, and much paler ventrally. Orange morph also exists that is bright orange dorsally and ventrally. Ears are very long. Wing membranes are dark brown and free of hairs. Females are on average larger than males, but there is significant overlap in measurements. There are no obvious sexual differences in pelage. Chromosomal complement has 2n = 42 and FNa = 78 in southern Africa. Echolocation call is multtharmonic and involves a steep FM sweep with peak frequencies at 50 kHz, 73 kHz, 90 kilz, and 113 kHz.

Habitat. Very wide variety of savanna and semiarid environments, including riverine and coastal forests, avoiding tropical rainforests and montane habitats, from sea level to elevations of more than 1500 m.

Food and Feeding. The Egyptian Slit-faced Bat eats various insects including orthopterans, moths, and beetles, taking different groups preferentially at different times of the year. It forages close to the ground where it gleans arthropods off low foliage and the ground. It detects prey from rustling sounds made as they move along the ground and then uses low-intensity echolocation calls to target and locate them.

Breeding. In southern Africa, breeding of Egyptian Slitfaced Bats is seasonal, with young born in early wet season (November). Young are fully grown by February and indistinguishable from adults by June. Litter size is one. Gestation is ¢.5 months, and young are suckled for c¢.2 months. A mother carries her non-volant young that attaches to her nipple.

Activity patterns. The Egyptian Slitfaced Bat roosts during the day in sheltered structures including caves, road culverts, hollow trees, Aardvark (Onrycteropus afer) burrows, and abandoned buildings. It can share its roost with several other species of bats, including Myotis spp., Miniopterus spp., and Rhinolophus spp. It emerges at dusk and returns back to the day roost at dawn. It uses regular night roosts located in its foraging area.

Movements, Home range and Social organization. Egyptian Slit-faced Bats roost singly or in large colonies of several hundred individuals. In cave systems, colonies can number up to a thousand individuals. In Swaziland, individual Egyptian Slit-faced Bats traveled an average of 1-1 km from the day roost to their foraging areas. In one study, average home range was 12-9 ha and overlapped with an average of four other bats. Sex ratio in the day roosts is heavily skewed toward females when they are in late pregnancy, although sex ratio of offspring is 1:1. Adult males move away from maternity roosts after breeding in June and do not return until after March the following year.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Wide geographic distribution and flexible habitat requirements are likely to ensure that the Egyptian Slit-faced Bat will not be threatened in the near term.

Bibliography. Aldridge et al. (1990), Benda, Dietz et al. (2008), Benda, Lugan et al. (2010), Bernard (1982a), Bernard & Happold (2013c), Bowie et al. (1999), Gray et al. (1999), Griffiths (1994, 1997), Happold, M. (2013ag), Largen et al. (1974), LaVal & LaVal (1980a), Mendelssohn & Yom-Tov (1999), Monadjem (2001, 2005b, 2006), Monadjem, McCleery & Collier (2015), Monadjem, Reside et al. (2009), Monadjem, Schoeman et al. (2010), Monadjem, Taylor et al. (2010), Rautenbach (1982), Rosevear (1965), Seamark & Bogdanowicz (2002), Smithers & Lobéao Tello (1976), Smithers & Wilson (1979), Taylor et al. (2017), Thomas et al. (1994), Van Cakenberghe & De Vree (1998), Verschuren (1957 1982).

Figures

1. Bates’s Slit-faced Bat (Nycteris arge), 2. Intermediate Slitfaced Bat (Nycteris intermedia), 3. Dwarf Slit-faced Bat (Nycteris nana), 4. Dja Slitfaced Bat (Nycteris major), 5. Malayan Slit-faced Bat (Nycteris tragata), 6. Javan Slit-faced Bat (Nycteris javanica), 7. Andersen’s Slit-faced Bat (Nycteris aurita), 8. Large Slitfaced Bat (Nycteris grandis), 9. Hairy Slitfaced Bat (Nycteris hispida), 10. Large-eared Slit-faced Bat (Nycteris macrotis), 11. Madagascar Slitfaced Bat (Nycteris madagascariensis), 12. Parisi’s Slitfaced Bat (Nycteris parisii), 13. Wood's Shitfaced Bat (Nycteris wood), 14. Gambian Slitfaced Bat (Nycteris gambiensis), 15. Egyptian Slitfaced Bat (Nycteris thebaica)

Distribution. Widely distributed throughout much of sub-Saharan Africa, from Senegal in W to Ethiopia and Somalia in E, S to South Africa (but absent from most of Congo Basin), and N along Nile River through Sudan to Egypt and across to Israel and Jordan ; there is an isolated population in Morocco and another one on W coast of Saudi Arabia along Red Sea S to Yemen .