1. A. N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, 119071 Moscow, Russia; e-mail: ds.kostin@yandex.ru
2. Addis Ababa University, Department of Zoological Sciences, Addis Ababa, Ethiopia
3. Department of Biology, Dire Dawa University, Ethiopia
4. Institute of Vertebrate Biology, Czech Academy of Sciences, Květná 8, 603 65 Brno, Czech Republic