1. Department of Natural Sciences, National Museums Scotland, Chambers Street, Edinburgh EH1 1JF, UK (corresponding author: )
2. Laboratory of Zoology, Department of Biology and Animal Physiology, University of Yaoundé I, Yaoundé, Cameroon
3. Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straße 17, 10315 Berlin, Germany
4. Global Wildlife Conservation, PO Box 129, Austin, TX 78767, USA