Otomops martiensseni, Matschie, 1897

Don E. Wilson & Russell A. Mittermeier, 2019, Molossidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 598-672 : 658

95.

Large-eared Giant Mastft Bat

Otomops martiensseni

French: Tadaride a grandes oreilles / German: Grof 3ohrige Riesenbulldogfledermaus / Spanish: Otomops de orejas grandes

Other common names: Giant Mastiff Bat, Large-eared Free-tailed Bat, Martienssen'’s Free-tailed Bat, Martienssen Bat, Martienssen's Big-eared Bulldog Bat

Taxonomy. Nyctinomus martiensseni Matschie, 1897 ,

“Plantago Magrotto unweit Tanga [= Magrotto Plantation, near Tanga, south-eastern Usambara Mountains, Tanzanial.”

Otomops martiensseni was previously considered to include O. harrisoni. In a 2018 molecular study by B. D. Patterson and colleagues, the species was shown to overlap in range and coexist with Harrison's Giant Mastiff Bat in Uganda, Kenya, and Rwanda. Monotypic.

Distribution. Widely but patchily in W Africa ( Guinea, Ivory Coast, and Ghana), C Africa ( Central African Republic, DR Congo, W Uganda, Rwanda, and Burundi), E Africa ( Kenya and Tanzania), and S Africa ( Angola, Zambia, Malawi, Zimbabwe, and E South Africa).

Descriptive notes. Head-body 87-103 mm, tail 39-52 mm, ear 29-42 mm, hindfoot 9-14 mm, forearm 60-68 mm; weight 25-38 g. Fur is similar to other giant mastiff bats, soft, dense, and dark brown with dark rusty-brown tinge, or blackish brown, darker on head and body, with pale brown or white band across shoulders, and a thin band of pale brown separating dark dorsal pelage from dark wing membrane on each side; belly is dark brown, throat paler. Face is pink with pig-like snout. Upper lip is expansible with many fine wrinkles and no spoon-hairs. Ears are rounded, fairly stiff, projecting forward well beyond snout; inner margins are joined together and to muzzle. Tragus is minute, antitragus absent, but a semicircular flap extends forward from base of ear and can be folded down to seal ear opening. There is no interaural crest. Gular sac is present in both sexes, well developed in adults. Wings and interfemoral membrane are blackish brown. Anterior of braincase is moderately elevated above plane of rostrum; zygomatic arches have prominent vertical projections; sagittal crest is moderate; lambdoid crest is low or absent; there is no helmet; anterior palatal emargination is very narrow and deep; basisphenoid pits are very deep and wide. Dentition is weak; P* is small but rising well above cingulum of P*; M® has third ridge equal to, or slightly shorter than, second; lower incisors are bicuspid; C, has cingula weakly developed and well separated. Chromosomal complement in Kenya —which could be either present species or Harrison’s Giant Mastiff Bat (O. harrisoni)—has 2n = 48 and FNa = 56 or 58.

Habitat. In southern Africa, particularly in the greater Durban area on the east coast of KwaZulu-Natal from Ballito in the north to Port Shepstone in the south, the Largeeared Giant Mastiff Batis closely associated with urban and suburban areas where it readily occupies the roofs of houses.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. In KwaZulu-Natal, Large-eared Giant Mastiff Bats have been found roosting under roofs of houses. A radio-tracking study by M. B. Fenton and colleagues in 2002, at Ballito, showed that individuals can use up to four different roosts within a two-week period, and they actively forage over extensive sugarcane plantations outside the town. Large-eared Giant Mastiff Bats produce QCF and CF calls with low peak frequency (c.11 kHz), narrow bandwidth (c.6 kHz), and long duration (c.24 milliseconds).

Movements, Home range and Social organization. Large-eared Giant Mastiff Bats roost communally in small to medium-sized colonies, although roosts with just one or two bats have been found. 24 colonies in roofs surveyed in the greater Durban area averaged a colony size of eleven individuals. Colonies typically comprise one dominant male with well-developed gular gland, and one or more adult females and their young, suggesting a harem structure. In five colonies surveyed by Fenton and colleagues in 2002, colony size varied from seven to 29 and all colonies comprised one male and 2-11 adult females. Based on radio-tracking conducted during the same study, bats regularly forage for distances of over 3 km from their day roosts, and occasionally bats were noted using temporary night-time roosts, which were up to 10 km or more from the day roosts.

Status and Conservation. Classified as Near Threatened on The IUCN Red List. The main threat seems to be disturbance of roostsites. Bats roosting in the attics of buildings in the Durban area were found to have suffered indirect poisoning due to toxic treatments of the timber in the roosts.

Bibliography. ACR (2017), Fenton, Jacobs et al. (2004), Fenton, Taylor et al. (2002), Long (1995), Monadjem, Taylor et al. (2010), Patterson et al. (2018), Ralph et al. (2015), Richards et al. (2017), Taylor (1998), Taylor et al. (1999), Yalden & Happold (2013).

Figures

14. Bonda Mastiff Bat (Molossus currentium), 15. Fenton’s Masuft Bat (Molossus fentoni), 17. Pallas’s Mastiff Bat (Molossus molossus), 18. Miller’s Mastiff Bat (Molossus pretiosus), 19. Black Mastiff Bat (Molossus rufus)

Distribution. Widely but patchily in W Africa ( Guinea , Ivory Coast , and Ghana ), C Africa ( Central African Republic , DR Congo , W Uganda , Rwanda , and Burundi ), E Africa ( Kenya and Tanzania ), and S Africa ( Angola , Zambia , Malawi , Zimbabwe , and E South Africa ).