Taphozous mauritianus, E. Geoffroy Saint-Hilaire, 1818

Bonaccorso, Frank, 2019, Emballonuridae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 350-373 : 351-352

3 . Mauritian Tomb Bat

Taphozous mauritianus

French: Taphien de Maurice / German: Mauritius-Grabfledermaus / Spanish: Tafozo de Mauricio

Other common names: Tomb Bat

Taxonomy. Taphozous mauritianus É. Geoffroy Saint-Hilaire, 1818 ,

Island of Mauritius .

Taphozous mauritianus is in the subgenus Taphozous . Monotypic.

Distribution. Much of sub-Saharan Africa, from Senegal E to W Ethiopia and S Somalia, and S to NE Namibia and E South Africa, including Bioko, Principe, São Tomé, Annobón, and Unguja (Zanzibar Archipelago) Is; also in Madagascar, Aldabra, Assumption, Comoros (Mayotte I), Mauritius, and Réunion Is.

Descriptive notes. Head-body c.76 - 88 mm, tail 15-28 mm, ear 12-22 mm, hindfoot 11-18 mm, forearm 58-65 mm; weight 20-36 g. There is no sexual dimorphism in general appearance and size, and both sexes have radio-metacarpal pouches. Dorsum of the Mauritian Tomb Bat appears to be grizzled due to tricolored hairs: whitish at tips, graybrown in middle, and pale brown at bases. Fur is sleek and close to body; it extends onto uropatagiumjust beyond point at which tail perforates the membrane. Venter is white, strongly contrasting dark appearance of dorsum. Sexually mature males have conspicuous gular pouch. Some adult females in Mozambique, Sudan, and Nigeria reportedly have gular sac and others do not, but when present, it is less developed than in males. In mature males, gular sac opens anteriorly and contains glands that produce secretions that pass through its anterior opening. Radio-metacarpal sacs are located at forward angles on each wing. These sacs are formed by fold ofskin stretched between radius and basaljoint ofmetacarpal offifth digit. Aspect ratio oflong, narrow wing is 8-2, which makes it difficult to maneuver in tight confines. Under experimental conditions, Mauritian Tomb Bats cannot manage a turn in a 1-m wide corridor. Metacarpals decline in length progressively from third to fifth digits. Second digit has only metacarpals, but there are two phalanges on third, fourth, and fifth digits. At rest, long narrow tip of wing is shortened as first phalanx of third digit folds forward and on top of metacarpal, while second phalanx folds down on bottom of first. Such folding ofwingtip facilitates efficient crawling on roost substrates. Posterior margin of interfemoral membrane (uropatagium) is supported on each side by strong calcar. Tail projects through middle of this membrane and above membrane as is typical in Emballonuridae . Ear is triangular. Tragus is ovalshaped and as broad (4-5 mm) as it is long. Long, thin postorbital processes of skull taper and curve down around eye sockets. Rounded braincase rises above plane of face, resulting in curved profile with little to no sagittal crest. Deep saucer-like depression in frontal area is apparent on face of live individuals. Posterior edge of palate ends abruptly at last molar, with gaps on inner edge of palate due to incomplete auditory bullae.

Habitat Moist savannas, open woodlands, and grasslands with more than 500 mm of rain per year, and riparian gallery forests and swamps along large rivers, from sea level to elevations of C.900 m. Mauritian Tomb Bats on Sao Tomé and Principe occur in cocoa plantations. Often found in anthropomorphic habitats (e.g. roosting under eaves of houses).

Food and Feeding. Mauritian Tomb Bats eat moths, alate termites {Macrotermes falciger), butterflies, and other insects. Like other species of tomb bats, they fly high and fast. During wet season, radio-tracked individuals from the day roost at Babalala Picnic Area, Kruger National Park, flew up to 5 km from their day roost to nightly feeding areas. Individuals forage independently, but subadults appear to fly with mothers.

Breeding. Given the large distribution of Mauritian Tomb Bats across the African continent, it is not surprising that they are polyestrous in wet tropical regions and monoestrous in more seasonal arid and temperate regions. Timing of parturition from region to region also varies depending on climate and latitude. In Zimbabwe, females were observed carrying a single young in October and were pregnant again in February; in northern Zaire, Tanzania, and Kenya, births occurred in April-May. After birth, single young cling to their mothers’ abdomens in flight, and they carry them until it can fly on their own. In tropical northern reaches of Kruger National Park, Mauritian Tomb Bats are migratory, regularly appearing in wet season at the Babalala Picnic Site to rear young but disappearing during dry season.

Activity patterns. Mauritian Tomb Bats emerge after dark and actively forage for several hours thereafter. At Babalala Picnic Area, a roosting group of 3-8 adult bats arrive each wet season in this mopane forest/grassland region. They roost by day at tops ofwooden posts that support a thatch-covered, open-air, circular structure, singly or as a breeding pair, with an adult male and adult female on each post Mauritian Tomb Bats also roost on cliffwalls with overhanging rock shelves and trunks of large trees where deep shade is available. They rest against roost substrate in vertical head-down postures, clinging with feet and thumbs. The species produces a multi-harmonic HDC-QCF call, with low peak frequency of 25-9 kHz, narrow bandwidth of 2-8 kHz, and intermediate duration of 7-4 milliseconds. Second and third harmonics are often present on a spectrogram.

Movements, Home range and Social organization. Mauritian Tomb Bats roost singly or in small groups of up to twelve individuals and remain alert while roosting. Some females at Babalala have a subadult clinging to their backs even though young are able to fly and seem to forage with their mothers. All bats at Babalala tolerate tourists walking past only 2 m below them. Mauritian Tomb Bats often roost in buildings inhabited by people. Young cling to breasts of their mothers, but subadults cling to dorsa of their mothers in day roosts until nearly adult size. Adults maintain minimum spacing of 10-15 cm in day roosts. Group members returning to a day roost emit a contact call, repeated at intervals of 2-3 seconds. Mauritian Tomb Bats and African Sheath-tailed Bats { Coleura afra ) intermingle in twilight zones of some caves. Some raptors that hunt at dusk and owls that hunt at night in Kruger National Park actively hunt bats, and Mauritian Tomb Bats probably fall prey to these carnivorous birds. Snakes also prey on Mauritian Tomb Bats. Trematodes {Anchitrema) are common endoparasites.

Status and Conservation. Classified as Least Concern on 77i? IUCN Red List. The Mauritian Tomb Bat has a large distribution and presumably large and stable overall population, and it is tolerant of habitat modification. It occurs in many protected areas in Africa including Kruger and Mapungubwe national parks in South Africa and Zombitse-Vohibasia and Ankarafantsika national parks in Madagascar.

Bibliography. Allen, G.M. (1939), Allen, J.A. (1917), Anciaux de aveaux (1983), Ansell (1978), Ansell & Dowsett (1988), Dengis (1996), Happold & Happold (1988,1990), Happold et al. (1987), Hayman & Hill (1971), Juste & Ibänez (1993a), Kingdon (1974), Lang & Chapin (1917b), Monadjem, Fahr, Mickleburgh etal. (2017), Rosevear (1965), Shortridge (1934), Skinner & Chimimba (2005), Smithers & Wilson (1979), Taylor (2000), Verschuren (1957), Wilson (1975).

Figures

On following pages: 4. Hamilton'sTomb Bat [Taphozous hamiltoni); 5. Hildegarde'sTomb Bat (Taphozous hildegardeae}; 6. Long-winged Sheath-tailed Bat (Taphozous longimanus); 7. Black-beardedTomb Bat (Taphozous melanopogoh); 8. Theobald'sTomb Bat (Taphozous theobaldi); 9. Indonesian Tomb Bat (Taphozous achates); 10. Arnhem Sheath-tailed Bat (Taphozous kapalgensis}; 11. Coastal Sheath-tailed Bat (Taphozous australis}; 12. Common Sheath-tailed Bat (Taphozous georgianus); 13. Hill's Sheath-tailed Bat (Taphozous hilli); 14. Troughton's Sheath-tailed Bat (Taphozous troughtoni); 15. Pel's Pouched Bat (Saccolaimus peli); 16. Bare-rumped Sheathtailed Bat (Saccolaimus saccolaimus); 17. Papuan Sheath-tailed Bat (Saccolaimus mixtus); 18. Yellow-bellied Sheath-tailed Bat (Saccolaimus flaviventris).

Distribution. Much of sub-Saharan Africa, from Senegal E to W Ethiopia and S Somalia, and S to NE Namibia and E South Africa, including Bioko, Principe, São Tomé, Annobón, and Unguja (Zanzibar Archipelago) Is; also in Madagascar, Aldabra, Assumption, Comoros (Mayotte I), Mauritius, and Réunion Is.