Funding for this research was provided by:
National Research Foundation (92788)
National Science Foundation (1416889)
Received: 21 November 2017
Accepted: 23 April 2018
First Online: 9 May 2018
Ethics approval and consent to participate
: Samples were collected under a permit (RES2015/26) issued by the Department of Agriculture, Forestry and Fisheries, South Africa.
: The authors declare that they have no competing interests.
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