Two recent genetic studies have shown that a significant number of species of bats in Europe accounted for probably another two species 'cryptic' or more (Ibañez et al. 2006; Mayer et al. 2007).
Miwili ya hivi karibuni masomo ya maumbile umeonyesha kwamba idadi kubwa ya aina ya popo katika Ulaya waliendelea kwa pengine aina nyingine mbili 'fumbo' au zaidi (Ibáñez et al. 2006; Mayer et al. 2007).