490.

Cryptic Myotis

Myotis crypticus

French: Murin cryptique / German: Kryptisches Mausohr / Spanish: Ratonero gris ibérico

Other common names: Cryptic Bat, Hidden Myotis

Taxonomy. Myotis crypticus Ruedi et al. in Juste et al, 2019,

“Cueva Cerravico, El Rasillo de Cameros, La Rioja ja, Spain (ca. 42°11'0"N, 2°44'20"W), 1400 m asl.”

Subgenus Myotis; myotis species group. See M. nattereri . The name M. nattereri helverseni was recently proposed by E. Coraman and colleagues in 2019 based on populations that are now included under this species; the name is considered a nomen nudum as the publication did not include a proper description for the name. Monotypic.

Distribution. N & C Spain, SE France, Italy including Sicily, and SW Austria; may occur on Corsica and Sardinia. Genetic analyses also supportits existence in W Alps, N limits of its distribution are not known.

Descriptive notes. Head—-body 40-50 mm,tail 32-46 mm, ear 14-1-17- 1 mm, hindfoot 6-6-9- 1 mm, forearm 36-3—- 42 mm; weight 5-12 g. The Cryptic Myotis is medium-sized, with very similar external morphology, skull characteristics, and completely overlapping measurements with all other members of the M. nattereri species complex. Despite this overlap, the Cryptic Myotisis slightly smaller than all otherspecies.It also has the typical fringe of hairs along rear edge of uropatagium, which distinguishesit from other species of Myotis . Nevertheless, there are some clear morphological differences between the Cryptic Myotis and Escalera’s Myotis ( M. escalerai), its sympatric cryptic species. In this case, tail membrane of the Cryptic Myotis has one row of relatively short bristles on its edge pointing outward, and Escalera’s Myotis has two rows of bristles, one pointing outward and the other pointing inward. Uropatagium is also surrounded by long S-shaped calcar without epiblema, and is inserted at base of toe rather than metatarsus, as in Escalera’s Myotis . Dorsal color is generally brownish to grayish, and venter is pale grayish to whitish. Hairs are long and shaggy, with dark bases and pale tips. Ears are relatively long, surpassing nose tip when flattened and presenting several folds at outer edges. Tragusis sharp and pointed, longer than one-half the ear length. Face is hairless and pink,especially around eyes, with narrow long and pointed muzzle. Feet are relatively small compared with other similar species and shorter than one-half the tibia length. Skull shapes are very similar, although slightly slimmer. Skull is small and delicate with high braincase and strongly concave forehead regions; there are no sagittal or occipital crests; very similar to Natterer’s Myotis ( M. nattereri) but has overall less flat skull (summit of skull located further forward), generally narrower skull and rostrum, and relatively longer rostrum. P?is more than one-half height and about three-quarters crown area of P* and is within tooth row; lower molars are myotodont.

Habitat. Reportedly montane areas, probably different types of forests (e.g. oak and beech), clearings for pasture, and alpine meadows up to elevations of ¢. 2000 m.

Food and Feeding. The Cryptic Myotis gleans prey, probably foraging in dense habitats and cluttered vegetated areas. It hunts very efficiently close to background vegetation and in reduced spaces where high maneuverability is essential. It probably hunts invertebrates (e.g. spiders and caterpillars) from surfaces of leaves or directly from the ground.

Breeding. During the maternity period, Cryptic Myotis roost in hollow trees and abandoned man-made structures, forming colonies with a few tens of individuals.

Activity patterns. The Cryptic Myotis roosts in tree holes and human buildings, in contrast to other cryptic species in the M. nattereri species complex (i.e. Escalera’s Myotis and the Zenati Myotis) that are strictly cave dwelling.

Movements, Home range and Social organization. Cryptic Myotis tend to congregate in large numbers during swarming in specific sites at elevations of 200-1500 m (e.g. in Switzerland, France, Spain, and Italy).

Status and Conservation. Not assessed on The IUCN Red List.

Bibliography. Coraman et al. (2019), Juste et al. (2019), Puechmaille, Allegrini et al. (2012), Ruedi et al. (2019), Salicini et al. (2011, 2012, 2013).