Mehely’s horseshoe bat is a medium-sized bat. Fur on the upperparts of the body varies in color from grey-brown to brown, pale on the underparts. In adults, clear boundary between upperparts and underparts coloration. Eyes small. Ears short, broad and lack a tragus. Broad wing, wider than long with rounded ends. Hind edge of nose-leaf tapered, concave at base. Lower edge of sella rounded and broad. Lower lip has three mental grooves. Tails short.
The bat is medium-sized for a member of the genus Rhinolophus, with pale lips and grey-brown ears and flight membranes. The fur is relatively thick, with the base of hairs grey-white. Ventral fur is almost white, while dorsal fur is grey-brown; the line between the dorsal and ventral sides is relatively sharp.
The bat is cave-dwelling, preferring areas of limestone with nearby water. It has been known to roost in caves with other horseshoe bats, hanging free on the cave roof.
The bat emerges at dusk, hunting low over the ground on warm hillsides and also among bushes and trees, preying on moths and other insects.
The constant frequency sound is between 105 and 112 kHz, with a short drop in frequency at the end of the signal, which normally lasts between 20 and 30 milliseconds. There is some frequency overlap with the lesser horseshoe bat and the Mediterranean horseshoe bat.
A behavioral study conducted by Puechmaille et al. (2014) revealed that the peak frequencies of echolocation calls emitted by male and female Rhinolophus mehelyi accurately reflect their body size and condition. In the experiment, larger males proved to have higher call frequencies that attracted females twice as often as males with lower call frequencies. In contrast, males appeared to choose females at random. This distinction suggests that females choose males based on their call frequency for the indirect benefits of having healthier and fitter offspring. The mating system is therefore comparable to a lek, making female mate choice a selection factor in the evolution of call frequency in males that may counter other selection pressures imposed by their ecological niche.
Localized (northern part of Western desert, Sakkara).
Body length 81–86 mm, forearm length 46.5 – 54.8 mm, 5th digit 57–67 mm, 3rd digit 71–83 mm, phalange 4.1 = 6.5–9.3 mm, phalange 4.2 = 17.4–21.5 mm.
Mehely’s horseshoe bat prefer to live in desert humid caves with moderate temperatures (<32° C) and roosts in worm caves.
Nocturnal bat. Insectivorous, feeding on moths, beetles and flies. Lives in groups of around 20+ individuals on walls or ceilings and mixed with other species. Mehely’s horseshoe bat uses echolocation (at a constant-frequency calls of 106 to112 kHz) to detect prey by emitting ultrasound from nose-leaf. Little information available on the breeding biology of Mehely’s horseshoe bat except that the breeding season takes place in January and female gives birth to a litter of two young once a year.