243.

Desert Long-eared Bat

Otonycteris hemprichii

French: Oreillard de Hemprich / German: Hemprich-Wiistengrof 3ohr / Spanish: Orejudo de Hemprich

Other common names: Common Desert Long-eared Bat, Hemprich’'s Desert Bat, Hemprich's Long-eared Bat

Taxonomy. Otonycteris hemprichii Peters, 1859,

type locality not given. Restricted by D. Kock in 1969 to Nile Valley between north of Aswan, Egypt and Chondek, Sudan.

Based on genetic data, Otonycteris is sister genus to New World Corynorhinus . This species previously included O. leucophaea as a synonym, but genetic and morphological data support their separation as distinct species. There is a clinal variation in mensural data across the range but genetic and morphological data support accepting three races, although respective range limits are unclear, especially between cinerea and jin. Race jin may be a distinct species, but further study is needed. Three subspecies recognized.

Subspecies and Distribution. O.h.hemprichiiPeters,1859—NAfricainMorocco,Algeria,Tunisia,NNiger,Libya,Egypt,andNSudan,SETurkey,LevantregioninSyria,Lebanon,Israel,Palestine,andJordan,SEIraq(tentatively),andtherestofMesopotamia.

O.h.cinereaSatunin,1909—mountainousareasofEArabia(atleastOmanandtheUnitedArabEmirates)andC&SIran.

O. h. jin Cheesman & Hinton, 1924 — lowland deserts of C & E Arabia, in Saudi Arabia and (tentatively) Qatar; also SE Iran.

Descriptive notes. Head—body 57-86 mm, tail 40-64 mm, ear 30-43- 4 mm, hindfoot 9-14 mm, forearm 50-70 mm; weight 18-19 g. The Desert Long-eared Bat is a robustly built vespertilionid, with relatively long, narrow muzzle. Compared with its only congener, the Turkestani Long-eared Bat ( O. leucophaea), muzzle is somewhat shorter and narrower, baculum smaller and more robust, braincase wider, auditory bullae much more inflated and generally larger (the most diagnostic difference between the two species), and coronoid process of mandible higher. Pelage is loose and soft with ventral pelage less dense; dorsally pale beige (with a cline, darker in east and much lighter in west); ventrally whitish to pure white. Ears yellowish brown; very long and well separated with smoothly convex inner and outer margins and rounded tip; antitragus very small; tragus long and tapers to blunt tip. Eyes comparatively large for the family. Wings very broad, and membranes thick and leathery, semi-translucent, pale yellowish brown near body, becoming pale grayish brown near middle and whitish near wingtips and edges. Tail moderately long and more or less fully enclosed by uropatagium, which attaches at ankle; calcar reaches less than halfway between ankle and tail tip on uropatagium. Unlike most vespertilionids, there are two sets of nipples in this genus. Penis (in both species) unusual in that glans is expanded dorso-ventrally and protrudes through two lateral swellings with third swelling on penis dorsal surface. Baculum crescent-shaped, dorsolaterally flattened, and relatively thick. Skull robust, rostrum broad and high; braincase elongated; interorbital constriction is narrow. Canines large and round in transverse section; P* large and canine-like; M? extremely reduced; lower incisors small, compressed, partly overlapping, and bicuspid; I, has small cusp on lingual side; P, small but within tooth row, separating P, and C,; lower molars are myotodont. Dental formula for both members of genus is11/3,C1/1,P 1/2, M 3/3 (x2) = 30. Chromosomal complement has 2n = 28, FN = 50, and FNa = 46 (Jordan).

Habitat. Arid rocky desert and semi-desert habitats with sparse xeric shrubbery. Recorded in both lowland and highland regions.

Food and Feeding. Feed on a variety of ground-dwelling prey, including Scorpiones, Araneae, Coleoptera, Chilopoda, and Solifugae . In Israel, however, diet was reported to include mainly Coleoptera (sometimes only Scarabaeidae), Heteroptera, and Diptera, which are typically flying insects. Orthoptera and Lepidoptera were also recorded in fecal samples from Iran. In captivity, the species was recorded eating geckos, although no vertebrate prey has been recorded in the wild. Feeds mainly by gleaning from ground; may also use aerial-hawking, especially when favored scorpion prey becomes scarce. Diet shifts through year. In Israel, scorpions made up 10% by volume of fecal samples in March but increased to 70% in August (during peak lactation). Although echolocation is an important means of finding prey, the species appears to cease echolocation occasionally when close to the ground, suggesting that it may be using vision or passive gleaning (listening for prey movement); this has been confirmed in laboratory studies involving scorpions, in which the bats would detect the scorpions by listening for their footsteps. After their scorpion prey was detected, they would immediately drop straight onto the moving scorpions, being stung frequently in the process. Once killed, the entire scorpion (including poison gland and stinger) were eaten; there was no preference for any particular species or size of scorpion. This suggests that the species is completely immune to the venom since no adverse effects were detected.

Breeding. Limited information available. Pregnancy estimated to begin by late March in Israel, with births taking place roughly in first week ofJune. Pregnant females have been recorded in May-June in United Arab Emirates. Lactating females in mid-June in Niger. Litter size probably two.

Activity patterns. Nocturnal, typically emerging c.40 minutes after sunset, almost always between 20:00 h and 21:00 h. In the Negev Desert, southern Israel, distances between roosts and foraging sites were 0-5- 9 km, and as distance increased, so did daily foraging time, mean daily foraging bout length, and first daily foraging bout length (mostly because of the increased distance the bats were flying). This species is well adapted to desert environments, being heterothermic and able to hibernate and enter shallow daily torpor. In Israel, individual females in both deep and shallow daily torpor were observed in their first two trimesters of pregnancy, with body temperatures frequently dropping as low as 15°C; during their third trimester of pregnancy, the bats only entered shallow torpor and their body temperatures always stayed above 29°C. Day roosts are typically in rock crevices and fissures and similarsites in buildings (cracks in stone walls); based on data from radio-tracked bats, these sites are constantly changed. They are considered “whispering” bats (passive gleaning), and have short, multiharmonic calls. Search-call shape is shallow FM with high intensity; start frequencies recorded at 34-2-68-3 kHz (Jordan), 28-5-32-8 kHz (Iran), 25-3-46-3 kHz (Israel), and average 42-4 kHz (Morocco); end frequencies 15-25-6 kHz (Jordan), 21-9-22-3 kHz (Iran), 18-25-3 kHz (Israel), and average 17 kHz (Morocco); peak frequencies 19-4-31-8 kHz (Jordan), 16-9-29-9 kHz (Iran), 20-5-34-1 kHz (Israel), and average 25-3 kHz (Morocco); durations 2-:9-11-9 milliseconds (Jordan), 3:4—4-1 milliseconds (Iran), average 5-2 milliseconds (Israel), and average 5-2 milliseconds (Morocco); interpulse intervals 72-302 milliseconds (Jordan) and 143-190-1 milliseconds (Iran). In one study, the first harmonic swept from 39 kHz to 22 kHz while the second harmonic had about one-half the intensity of the first and swept from 77 kHz to 43 kHz (average peak frequencies of 30 kHz forfirst harmonic and 54-5 kHz for second harmonic); the third harmonic was weak; average pulse duration was 2-5 milliseconds with interpulse interval 131 milliseconds.

Movements, Home range and Social organization. Roosts in small groups, females and Juveniles typically in maternity colonies of 2-18 clumped together, whereas males typically roost alone. Social behavior is not well studied.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Widespread but locally rare, although found quite regularly at some sites. There are currently no major threats, although it is affected by pesticide use.

Bibliography. ACR (2018), Arslan & Zima (2014), Benda & Gvozdik (2010), Benda, Andreas et al. (2006), Benda, Dietz et al. (2008), Benda, Faizolahi et al. (2012), Benda, Luan et al. (2010), Benda, Spitzenberger et al. (2014), Daniel (2005), Daniel et al. (2008, 2010a, 2010b), Davis (2007), Disca et al. (2014), Fenton, Shalmon & Makin (1999), Gharaibeh & Qumsiyeh (1995), Hackett et al. (2014), Holderied et al. (2011), Hoofer & Van Den Bussche (2001), Horéagek (1991, 2013), Kock (1969d), Korine et al. (2013), Marom et al. (2006), Monadjem, Aulagnier, Hutson & Benda (2017), Qumsiyeh & Bickham (1993).