Asellia tridens (E. Geoffroy Saint-Hilaire, 1813)

Don E. Wilson & Russell A. Mittermeier, 2019, Hipposideridae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 227-258 : 229-230

4.

Geoffroy’s Trident Leaf-nosed Bat

Asellia tridens

French: Asellia trident / German: Nordafrikanische Dreizackblattnase / Spanish: Asellia tridente

Other common names: Geoffroy’s Trident Bat

Taxonomy. Rhinolophus tridens É. Geoffroy Saint-Hilaire, 1813 ,

near Luxor, Egypt.

Up to four subspecies have at times been recognized within this species, but recent molecular work suggests the existence of just two. Two subspecies recognized.

Subspecies and Distribution.

A. t. tridens E. Geoffroy Saint-Hilaire, 1813 widespread in N Africa, from Morocco, Mauritania, and Senegal E to Egypt, Sudan, Eritrea, Ethiopia, Djibouti, and Somalia.

A. t. murraianaj. Anderson, 1881 widely in the Middle East, including Syria, Iraq, Israel, Palestine, Jordan, Arabian Peninsula, and Iran, and E to W Afghanistan and S Pakistan.

Descriptive notes. Head-body 41-60 mm, tail 16-29 mm, ear 14-22 mm, hindfoot 8-10 mm, forearm 45-55 mm; weight 6-13 g. Geoffroy’s Trident Leaf-nosed Bat is the largest species in the genus. Muzzle is relatively short with large and distinctive noseleaf that has three subtriangular projections from its posterior margin. Pelage is beige or pale brownish gray dorsally, somewhat paler ventrally. Chromosomal complement has 2n = 50 and FN = 62.

Habitat. Geoffroy’s Trident Leaf-nosed Bat inhabits a variety of desert and semi-desert habitats where it is mostly associated with oases and dry riverbeds. It generally occurs at low elevations, but may occur up to 2000 m.

Food and Feeding. Geoffroy’s Trident Leaf-nosed Bat forages by flying low and hawking a variety of large insects including beetles, moths, flies, and grasshoppers.

Breeding. Apparently, Geoffroy’s Trident Leaf-nosed Bat is a seasonal breeder, giving birth to a single young in the boreal summer. In Africa, pregnant females have been reported in April and May, and dependent young in July. In the Middle East, females are pregnant in April-June, with births in June-July followed by 40 days of lactation.

Activity patterns. Geoffroy’s Trident Leaf-nosed Bat roosts during the day in a wide range of situations including caves, mines, rock caverns, underground irrigation channels, and anthropogenic structures such as buildings, cellars, and tombs. It typically departs from its roost shortly after sunset, with males showing two peaks of activity during the night but females only one; both sexes have the greatest activity period in the hour immediately after sunset, with males showing a second peak in the early hours of the morning. Echolocation call includes a variable CF component of 115-120 kHz that varies individually and is negatively correlated with the size of the bat.

Movements, Home range and Social organization. Geoffroy’s Trident Leaf-nosed Bat roosts in small to very large colonies, with up to 5000 individuals having been reported from a cave in Iran. Roosts are usually occupied by this species alone, although it may occasionally share its roost with other bats including the Egyptian Rousette ( Rousettus aegyptiacus), the Persian Trident Bat {Triaenopspersicus), and mouse-tailed bats {Rhinopoma spp.). Numbers of bats roosting typically vary with season, and sexual segregation has also been reported. Pregnant females form maternity roosts. Throughout much of the Middle East, bats disappear during the boreal winter, reappearing in April-May presumably because they migrate between summer and winter sites. Both sexes put on fat in the boreal autumn before migration. Bats move c.1-5-2 km between roosting and foraging sites.

Status and Conservation. Classified as Least Concern on The IUCN Red, List. Its large distribution, often in remote areas and harsh landscapes, suggests that this species ought to be relatively secure.

Bibliography. Al-Robaae (1966), Amichai et al. (2013), Aulagnier (2013b), Benda, Andreas et al. (2006), Benda, Dietz et al. (2008), Benda, Faizolâhi et al. (2012), Benda, Lucan et al. (2010), Benda, Spitzenberger et al. (2014), Benda, Vallo & Reiter (2011), Bogdanowicz & Owen (1998), Bray & Benda (2016), Brasset & Caubère (1960), De-Blase (1980), Feldman et al. (2000), Gustafson & Schnitzler (1979), Harrison & Bates (1991), Jones et al. (1993), Koch-Weser (1984), Kock (1969d), Kowalski & Rzebik-Kowalska (1991), Fye (1972), Qumsiyeh (1985), Qumsiyeh & Schütter (1981), Whitaker et al. (1994).

Figures

1. Arabian Trident Leaf-nosed Bat (Asellia arabica), 2. Somalian Trident Leaf-nosed Bat (Asellia italosomalica), 3. Patrizi’s Trident Leaf-nosed Bat (Asellia patrizii), 4. Geoffroy’s Trident Leaf-nosed Bat (Asellia tridens), 5. Greater Leaf-nosed Bat (Doryrhina camerunensis), 6. Telefomin Leaf-nosed Bat (Doryrhina corynophyllus), 7. Cyclops Leaf-nosed Bat (Doryrhina cyclops), 8. Hill’s Leaf-nosed Bat (Doryrhina edwardshilli), 9. Fly River Leaf-nosed Bat (Doryrhina muscinus), 10. Semon’s Leaf-nosed Bat (Doryrhina semoni), 11. Northern Leaf-nosed Bat (Doryrhina stenotis), 12. Wollaston’s Leaf-nosed Bat (Doryrhina wollastoni), 13. Commerson’s Leaf-nosed Bat (Macronycteris commersonii), 14. Madagascar Cryptic Leaf-nosed Bat (Macronycteris cryptovalorona), 15. Giant Leaf-nosed Bat Macronycteris gigas rench: (Phyllorhine géante), 16. Sao Tome Leaf-nosed Bat Macronycteris thomensis rench: Phyllorhine de (Sao Tomé), 17. Striped Leaf-nosed Bat (Macronycteris vittatus), 18. Dong Bac Trident Bat (Aselliscus dongbacanus), 19. Stoliczka’s Trident Bat (Aselliscus stoliczkanus), 20. Temminck’s Trident Bat (Aselliscus tricuspidatus), 21. East Asian Tailless Leaf-nosed (Bat Coelopsfrithii), 22. Malayan Tailless Leaf-nosed Bat (Coelops robinsoni), 23. Solomons Leaf-nosed Bat (Anthops omatus)

Subspecies and Distribution. A. t. tridens E. Geoffroy Saint-Hilaire, 1813 widespread in N Africa, from Morocco , Mauritania , and Senegal E to Egypt , Sudan , Eritrea , Ethiopia , Djibouti , and Somalia . A. t. murraianaj. Anderson, 1881 widely in the Middle East, including Syria , Iraq , Israel , Palestine , Jordan , Arabian Peninsula, and Iran , and E to W Afghanistan and S Pakistan .