Hypsugo savii (Bonaparte, 1837)

Don E. Wilson & Russell A. Mittermeier, 2019, Vespertilionidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 716-981 : 810

97.

Savi’s Pipistrelle

Hypsugo savii

French: Vespére de Savi / German: Alpenfledermaus / Spanish: Murciélago montanero

Taxonomy. Vespertilio savii Bonaparte, 1897 ,

Pisa, Tuoi ,

Hypsugo savii is included within the Eurasian clade closely related to H. alaschanicus , H. ariel , and H. arabicus . Hypsugo alaschanicus has often been included under H. savii as a subspecies, but morphological and genetic data support their status as separate species. Specimens from Myanmar that were previously included in H. savii under the subspecies austenianus are now considered to represent H. pulveratus . There are four highly divergent lineages within H. savii that may ultimately represent distinct species; the Moroccan lineage, south-west European lineage (south Iberia to Switzerland), Levant lineage, and south-east European and Anatolian lineage (along with some specimens in Israel). Specimens from the Caucasus to India have not yet been compared genetically to other populations and further studies are needed. Four subspecies are tentatively recognized, and the name austenianus (from Meghalaya) is only tentatively recognized as a subspecies, although it may represent this species, H. pulveratus , or a distinct species. The subspecific name ochromixtus is replaced with the name darwini, which has priority since it is the older name available for that lineage; it has been suggested that this taxon represents a distinct species (referred to as H. cf. darwini in recent studies). Four subspecies recognized.

Subspecies and Distribution.

H.s.saviiBonaparte,1837—SC&EEuropefromItalytoBalkans,Anatolia,RhodesI,Levant,Crete,andCyprus.DistributionhasbeenexpandingintoCEuropeinthelast30years.

H.s.austenianusDobson,1871—knownonlyfromtypelocalityinNEIndia(KhasiHills,Meghalaya).

H.s.caucasicusSatunin,1901—CrimeaandCaucasusEtoWKazakhstan,WChina,andNWIndia.

H. s. darwini Tomes, 1859 — SW Europe from Iberia to Switzerland including Balearics, Corsica,Sicily, Sardinia, and Montecristo I, and N Africa from N Morocco to N Tunisia along with Canary and Cape Verde Is ( Sao Vicente and Santiago).

Descriptive notes. Head—body 40-55 mm, tail 31-43 mm, ear 12-15 mm, hindfoot 7-9 mm, forearm 31-4-37-9 mm; weight 5-9 g. Savi’s Pipistrelle is similar in appearance to the Eurasian Particolored Bat ( Vespertilio murinus ), but considerably smaller, with brown dorsal fur (although almost always dark, with very variable coloration from blackish to pale brown, with yellowish and golden tips) and ventral side very distinctly paler, whitish-grayish. There may also be dark reddish spots between ears, at corner of mouth, and on shoulders (especially in subspecies darwin). Ears are short; tragusis comparatively broad. Skin is remarkably dark, as in the Common Pipistrelle ( Pipistrellus pipistrellus ) or the Eurasian Serotine ( Eptesicus serotinus ). Dark wings attach to base of toes; last two vertebrae emerge from edge of uropatagium. Penis is characteristic, and bends at right angle toward tail. Baculum is rather elongated, stout, slightly flattened, and distally thickened (rounded and broadened epiphysis in both sides). This species can also be confused with the Northern Serotine ( E. nilssonii ). Profile of forehead region is weakly concave to almost straight; there is no occipital helmet; condylobasal lengths are 12-3-14-2 mm. I* is bicuspid; P? is minute and displaced laterally (in 10-40% of individuals it can also be absent); and lower molars are myotodont. Chromosomal complement has 2n = 44 and FNa = 50.

Habitat. Although Savi’s Pipistrelle is typical of mountain habitats within a Mediterranean distribution,it can be found from sea level up to elevations of 3000 m.It is an opportunist species that can forage in a variety of habitats, ranging from woodlands to grasslands, coastal wetlands, or even urban areas, in gardens and parks. It is abundant over water and riparian forests, but is often rare inside dense forests. It seems to favor mosaics of cultivation, different types of bush (e.g. maquis and garrigue), karstic areas, and cliffs.

Food and Feeding. Savi’s Pipistrelle hunts insects by aerial-hawking. It tends to hunt individually or in small groups, never close to ground (heights of 2-100 m aboveground). Common foraging sites include space around streetlamps, along cliffs, meadows and pastures,or riparian habitats or ponds where insects are abundant. Savi’s Pipistrelles mainly feed on Lepidoptera , Hymenoptera , and Diptera , but also Neuroptera , Coleoptera , Trichoptera , and Hemiptera , and others, depending on availability. In meadows and pastures, cicadellids might represent an important food for this species, whereas in forests and highly cluttered environments swarming insects such as flying ants were abundantin its feces.

Breeding. Maternity colonies are commonly formed by some tens of individuals, in rock crevices, usually long and narrow, or vertical cracks. Adult females give birth from earlyJune to late July, and usually produce twins. Mating occurs in August-September.

Activity patterns. Savi’s Pipistrelles emerge immediately after sunset, or sometimes even before it. Activity is higher during the first and last part of the night, but occasionally they can forage all night if needed. Flight pattern is straighter and more predictable than in Pipistrellus spp. , faster and with fewer changes of direction. Roosts are usually in rock crevices, under bark or in man-made structures; occasionally, they are in the entrances of caves or under rocks on the ground. During winter, this species hibernates in underground sites. Echolocation has QCF calls of ¢.16 milliseconds, with pulse rate of 7-8 pulses/second while foraging and 3-4 pulses/second when commuting. Frequencies of maximum energy are 30-35 kHz, higher than in the Northern Serotine, with a small overlap with Kuhl's Pipistrelle ( Pipistrellus kuhliz). Although reported to have very distinctive social calls with ascending frequency pulses, it is now known to have a broad range of social calls which are used in different circumstances; thus, its identification through social calls is less reliable than was previously thought.

Movements, Home range and Social organization. It is highly likely that Savi’s Pipistrelle migrates, but the longest reported movementis ¢. 250 km; this figure isitself uncertain, as the origin of the information is unknown. Swarming period occurs between August and September. This species roosts in colonies, the largest reported being in Croatia, with up to 70 individuals.

Status and Conservation. Classified as Least Concern on The IUCN Red List. In Europe it is relatively abundant, especially around the Mediterranean, while in the eastern limits ofits distribution, densities are quite low.

Bibliography. Arlettaz et al. (1993), Aulagnier (2013j), Bates et al. (2005), Beck (1995), Benda, Faizolahi et al. (2012), Benda, Georgiakakis et al. (2008), Benda, Hanak et al. (2007), Datzmann et al. (2012), Dietz & Kiefer (2016), Dondini et al. (2016), Hoofer & Van Den Bussche (2003), Horatek & Benda (2004), Hutterer et al. (2005), Ibanez et al. (2006), Jahelkové et al. (2014), Juste & Paunovi¢ (2016¢c), Lehotska & Lehotsky (2006), Mayer et al. (2007), Molur et al. (2002), Pacifici et al. (2013), Paunovi¢ et al. (2015), de Paz & Benzal (1989), Reina et al. (1995), Reiter et al. (2010), Riccucci & Lanza (2014), Ruedi & Arlettaz (1991), Schober & Grimmberger (1998), Simmons (2005), Spitzenberger (1997), Trujillo (1991), Trujillo et al. (2012), Uhrin et al. (2015), Valentina et al. (2017), Veith et al. (2011).

Figures

94. Fairy Pipistrelle (Hypsugo ariel), 95. Lanza’s Pipistrelle (Hypsugo lanzai), 96. Arabian Pipistrelle (Hypsugo arabicus), 97. Savi’s Pipistrelle (Hypsugo savii), 98. Alashanian Pipistrelle (Hypsugo alaschanicus), 99. Cadorna’s Pipistrelle (Hypsugo cadornae), 100. Joftre’s Pipistrelle (Hypsugo joffrei), 101. Chinese Pipistrelle (Hypsugo pulveratus), 102. Chocolate Pipistrelle (Hypsugo affinis), 103. Pungent Pipistrelle (Hypsugo mordax), 104. Peters’s Pipistrelle (Hypsugo petersi), 105. Long-toothed Pipistrelle (Hypsugo dolichodon), 106. Burmese Pipistrelle (Hypsugo lophurus), 107. Red-brown Pipistrelle (Hypsugo kitcheneri), 108. Brown Pipistrelle (Hypsugo imbricatus), 109. Big-eared Pipistrelle (Hypsugo macrotis), 110. Vordermann’s Pipistrelle (Hypsugo vordermanni), 111. Anchieta’s Pipistrelle (Hypsugo anchieta), 112. Kirindy Pipistrelle (Hypsugo bemainty), 113. Mouse-like Pipistrelle (Hypsugo musciculus), 114. Broad-headed Pipistrelle (Hypsugo crassulus), 115. Eisentraut’s Pipistrelle (Hypsugo eisentrauti), 116. Schlieffen’s Bat (Nycticeinops schlieffenii), 117. Moloney’s Mimic Bat (Mimetillus moloneyi)

Subspecies and Distribution. H.s.saviiBonaparte,1837—SC&EEuropefromItalytoBalkans,Anatolia,RhodesI,Levant,Crete,andCyprus.DistributionhasbeenexpandingintoCEuropeinthelast30years. H.s.austenianusDobson,1871—knownonlyfromtypelocalityinNEIndia(KhasiHills,Meghalaya). H.s.caucasicusSatunin,1901—CrimeaandCaucasusEtoWKazakhstan,WChina,andNWIndia. H. s. darwini Tomes, 1859 — SW Europe from Iberia to Switzerland including Balearics, Corsica ,Sicily, Sardinia, and Montecristo I, and N Africa from N Morocco to N Tunisia along with Canary and Cape Verde Is ( Sao Vicente and Santiago).