94.

Fairy Pipistrelle

Hypsugo ariel

French: Vespére ariel / German: Elfen-Zwergfledermaus / Spanish: Hypsugo ariel

Other common names: Ariel Pipistrelle, Bodenheimer's Pipistrelle, Desert Pipistrelle, Egyptian Desert Pipistrelle

Taxonomy. Pipistrellus ariel Thomas, 1904,

“Eastern Egyptian desert, lat. 22° N., long. 35° E. Lat. [Sudan]. 2000 feet [= 610 m].”

The genus Hypsugo is often subsumed into Pipistrellus, and several species have repeatedly been switched around as belonging to Pipistrellus, Neoromicia, or Hypsugo . Genetic data place the currently listed members of Hypsugo within Vespertilionini along with Neoromicia but to the exclusion of Pipustrellus (which is in Pipistrellini). Hypsugo as currently defined remains paraphyletic and, based on limited species sampling, Eurasian species (true Hypsugo) appear to form a monophyletic clade sister to the Australasian genera of Vespertilionini, whereas the African species may be better placed in Nycticeinops ( H. eisentrauti and H. crassulus) or Neoromicia (H. anchieta and H. bemainty). These projected transfers are withheld for the present, as to date not all African species of Hypsugo ( H. musciculus) and Neoromicia have been assessed phylogenetically, so the full picture is not yet clear. Hypsugo ariel is often placed in Pipustrellus, but genetic data clearly situate it in Hypsugo, within the Eurasian (true Hypsugo) clade, close to H. arabicus and H. savii . Hypsugo ariel includes bodenheimeri as a synonym, based on genetic and morphological data. Monotypic.

Distribution. Palestine, S Israel, SWJordan, NE Egypt (Sinai), NE & SC Sudan, W Saudi Arabia, Yemen, and SW Oman; it may occur in SE Egypt, and there is a purported record from C Kenya, but these need verification.

Descriptive notes. Head-body 35-45 mm, tail 32-44 mm, ear 9-14-1 mm, hindfoot 5-6 mm, forearm 28-1-33-7 mm; weight 2:3—4-8 g. Pelage of the Fairy Pipistrelle is not dense; dorsally it is pale pinkish brown to pale grayish cream or off-white cream, with underlying color showing through (hairs are blackish brown basally); ventrally it is generally paler brownish cream to off-white (hairs with blackish-brown base and pale grayish-cream tip). Bare face, ears, limbs, and digits are pinkish to dark pinkish brown. Ears are relatively short with convex inner margins, concave outer margins, and rounded tip; tragus has maximum breadth thatis only slightly less than length of its anterior margin, straight anterior margin, smoothly convex posterior margin with distinct lobule basally, and rounded tip. Membranes are pale brown and semitranslucent (uropatagium is apparently lighter than wings); Postcalcarial lobe is very narrow and tail projects slightly beyond uropatagium (last two vertebrae). Penisis relatively short with glans covered in long fine hairs. Baculum is short (1-4-1-8 mm) with upturned tip; shaft is wide in dorsal view, gradually widening just before narrowed and pointed tip, and thinner in lateral view; base is bulbous and non-bifurcated. Skull is small and gracile; braincase is relatively narrow and moderately high; rostrum is flattened and relatively narrow; forehead when viewed laterally is strongly concave; sagittal crest is extremely reduced and lambdoidal crests are absent. I” varies between unicuspid and bicuspid; I? is about two-thirds length of I?; P* is minute and sometimes not visible above gum and displaced lingually; C' and P* are in contact; and lower molars are myotodont. Dental formula for all members of Hypsugois 12/3, C 1/1, P 2/2, M 3/3 (x2) = 34 (but see H. alaschanicus and H. musciculus).

Habitat. Rocky areas, deserts, and semi-deserts, where it often occurs around oases and other water bodies. Also known to occur around farms and irrigated areas in Jordan. Recorded at elevations of 345-1224 m.

Food and Feeding. Foraging individuals were captured in Jordan in a rocky canyon, at a small spring, and in an old village garden, suggesting Fairy Pipistrelles mostly forage in open areas, although they have also been observed foraging around trees. They seem to fly close to the ground while foraging and are fairly maneuverable. Fifty-five fecal pellets in Jordan contained a variety of insects, including Coleoptera, Lepidoptera, Auchenorrhyncha, Heteroptera, Hymenoptera, Nematocera, Neuroptera, and Trichoptera, being dominated by small Lepidoptera in Al Ghal, and Coleoptera in Wadi Al Hasa. Digestive tracts in Sinai, Egypt, showed high proportions (80% by volume) of small Coleoptera (including 60% Scarabaeidae and 20% Tenebrionidae), along with smaller amounts of Brachycera (10%), Lepidoptera (7%), and Auchenorrhyncha (3%). Fairy Pipistrelles appear to shift their diet based on availability. They have also been recorded feeding on arachnids, which suggests that they may glean prey occasionally.

Breeding. In Jordan, a single pregnant female was captured in May with two well-developed fetuses, suggesting that births probably occur around late May in that region. In Palestine and Israel, the Fairy Pipistrelle appears to give birth in late April to May, as a pregnant female was captured in April with two embryos, and lactating females were captured from May to July. In Israel, subadults were first captured in June and made up 50% of individuals captured in July and August.

Activity patterns. The Fairy Pipistrelle is known to roost in cracks and crevices in rocks during the day, foraging by night. In the Negev HighlandsofIsrael, this species expressed a bimodal nightly activity pattern, being most active during the first and last hoursof the night. It is active throughout the year, but during a summer night, there may be as many as 20 times more individuals active than on winter nights. Fairy Pipistrelles hibernate during winter, but arouse to forage and have been captured at temperatures as low as 11°C. Search-call shapeis a steep FM/QCFsweep with a very short CF portion; records fromJordan had start frequencies of47-7-75 kHz, end frequencies of 30-47-4 kHz, peak frequencies of 43-4—49 kHz, durations of 2-4-7-2 milliseconds, and interpulse intervals of 45-193 milliseconds. In Sinai, Egypt, start frequencies were 48-3-87 kHz, end frequencies 41-6-45-7 kHz, peak frequencies 44-3—49-1 kHz, durations 2-6-5-9 milliseconds, and interpulse intervals 31-8-186 milliseconds. In Israel, start frequencies were 45-83.9 kHz (mean 56-3 kHz), end frequencies 42-9—49-8 kHz (mean 46-1 kHz), peak frequencies 42-8-53-7 kHz (mean 48-2 kHz), and duration averaged 3-2 milliseconds.

Movements, Home range and Social organization. A colony of 20 Fairy Pipistrelles was observed leavingits castle ruin roost in Saudi Arabia. This species probably roosts in relatively small groups or solitarily.

Status and Conservation. Classified as Data Deficient on The IUCN Red List (as Pipistrellus ariel). The full distribution of the species is still uncertain, and very little is known of threats. It may be threatened by agricultural expansion and general habitat loss.

Bibliography. ACR (2018), Aloufi et al. (2016), Benda & Aulagnier (2008), Benda, Al-Jumaily et al. (2011), Benda, Dietz et al. (2008), Benda, Lucan et al. (2010), Benda, Nasheret al. (2017), Benda, Reiter et al. (2016), Gaucher & Harrison (1995), Hackett et al. (2017), Makin & Harrison (1988), Mayer et al. (2007), Razgour et al. (2011), Riskin (2001), Van Cakenberghe & Happold (2013f), Whitaker et al. (1994), Yom-Tov (1993), Yom-Tov & Kadmon (1998), Yom-Tov etal. (1992).