435.

Alcathoe Whiskered Myotis

Myotis alcathoe

French: Murin alcathoé / German: Nymphenfledermaus / Spanish: Ratonero bigotudo pequeno

Other common names: Alcathoe Bat, Alcathoe Myotis, Alcathoe Whiskered Bat

Taxonomy. Myotis alcathoe von Helversen & Heller in von Helversen et al., 2001,

“netted over a small stream, the Fournikos Potamos, near the village of Kleistos (39°05’N, 21°49°E), Novos Evritanias, Greece.

Subgenus Myotis (62 species); alcathoe species group (2 species). Myotis alcathoe and M. hyrcanicus are sister to one another and appear to form a clade basal to the rest of the subgenus Myotis . Two subspecies recognized.

Subspecies and Distribution. M.a.alcathoevonHelversen&Heller,2001—patchilythroughalmostallEurope,fromNSpaintoGermany,includingBritain,andEtoSWUkraineandNWTurkey(EThrace);therearealsoecholocationcallsfromSSwedenthatcertainlyrepresentthisspeciesandtheremayalsoberecordsfromLatvia.

M. a. circassicus Benda, Gazaryan & Vallo, 2016 — N slopes of Greater Caucasus in Russia and Abkhazia (Georgia); possibly also found in North Ossetia — Alania Republic (Russia), NE Turkey (Artvin and Erzurum provinces), and Azerbaijan.

Descriptive notes. Head-body 39-44 mm,tail 36-37 mm, ear 11:4-14- 3 mm, hindfoot 5-1-5-8, forearm 29-7-34- 6 mm; weight 3-5-5- 5 g. The Alcathoe Whiskered Myotis is one of the smallest European Myotis, with brownish and reddish upperparts and lighter brown underparts; hair is comparatively long (6-8 mm) dark at base with light brown tips. fur can be entirely grayish or brownish in young bats. Wings are fairly dark, brownish or blackish, although lighter than in the Common Whiskered Myotis ( M. mystacinus), and always attached to fifth toe. Ears are short and pale; short tragus has clear notch on edge. Nostrils are heart-shaped. Face is mainly furred, but pinkish bare skin is much paler than that of the Common Whiskered Myotis . Feet, legs and thumbs are remarkably short and small; calcar is slender and relatively long; tail membrane is less pigmented on the edge near the calcar. Penis is narrow from base to tip; baculum is short (c. 0-5 mm long) and broad. Skull is similar to that of the Common Whiskered Myotis and Brandt's Myotis ( M. brandtii) but has higher braincase. P? and P° are tiny and pressed against C1 and P* P* has a clearly developed cusp; upper molars have protoconules. Chromosomal complement has 2n = 44 and FNa = 52 (Greece).

Habitat. The Alcathoe Whiskered Myotis is usually found near streams in mature moist forests, which have complex structure with deciduous trees such as Quercus (Fabaceae); Tilia (Malvaceae); and Alnus and Betula (Betulaceae); also riparian forest and montane Quercus, Carpinus (Betulaceae) and Fagus (Fagaceae) forests. It seem to favor sloping ground. Positively selects old mature forests due to the large numbers of decaying trees for roosting and maternity colonies. Commonly found in habitats also occupied by Bechstein’s Myotis ( M. bechsteinii) and Brandt's Myotis .

Food and Feeding. The Alcathoe Whiskered Myotis forages at forest edge byrivers, flying mostly in the canopy and hunting above water. Typically catches prey in flight but the presence of spiders and other non-flying animals suggests it may also capture prey from surface of leaves or ground. Usually feeds on small insects such as mosquitoes, small moths,flies, ants and beetles; also spiders. Locally it has been found to specialize on Nematocera, along with some caddisflies, moths, and spiders.

Breeding. Maternity colonies are normally in the canopy, and typically contain few adult females with their youngsters; males normally roost alone. Colonies tend to be small but rarely grow up to ¢.80 bats. Maternity roosts are very ephemeral, as the species switches roosts every few days. Females can give birth up to mid-July.

Activity patterns. The Alcathoe Whiskered Myotis usually roosts in fissures behind bark, and in holes in broken and rotten wood, 15-22 m aboveground. It moves from one roost to another frequently, even daily in many cases. It emerges 30-60 minutes after sunset and has a bimodal night activity pattern. Echolocation call is one of the highestfrequency types within Myotis, with relatively long (2:5—4 milliseconds) pulses. Pulses start at 120 kHz and end at c.46-32 kHz, with characteristic frequency of c.53 kHz. This is probably an adaptation to cluttered habitats and dense vegetation; the high frequency, combined with broad wings and high maneuverability, allow the species to fly in reduced spaces full of obstacles, and thus occupy a difficult niche typical of old forests. Echolocation calls are quite weak in terms of intensity, and are difficult to detect at distances over 10 m.

Movements, Home range and Social organization. The Alcathoe Whiskered Myotis usually moves to nearby rivers or streams at dusk, moving not more than 3-6 km each night to hunting areas; hunting zones are frequently changed. In winter, this species moves to caves or other small cavities in forest, although hibernation colonies have also been found in trees. Solitary animals can be found all year in small clusters. During the first half of August, some caves are used as swarming sites; these are often shared with other similar species, such as Bechstein’s Myotis and Brandt's Myotis .

Status and Conservation. Classified as Data Deficient on The IUCN Red List, due to its recent description. The Alcathoe Whiskered Myotis was initially known only from Greece and Hungary, and it was thought to have a very restricted distribution; now known to be more widespread. It occurs at low densities and in scattered populations, with limited suitable habitat available. Main threats appear to include habitat loss and fragmentation, especially due to wood extraction; collisions with vehicles also said to be significant.

Bibliography. Agirre-Mendi et al. (2004), Ahlén (2010), Alcalde (2009), Bashta et al. (2011), Benda & Karatas (2005), Benda, Gazaryan & Vallo (2016), Benda, Ruedi & Uhrin (2003), Boston et al. (2011), Danko et al. (2010), De Pasquale & Galimberti (2014), von Helversen et al. (2001), Jan et al. (2010), Luan et al. (2009), Niermann et al. (2007), Nyssen et al. (2015), Pavlini¢ et al. (2012), Rehék etal. (2008), Sachanowicz et al. (2012), Spitzenberger et al. (2008), Volleth & Heller (2012).