[Mystery bird] Zitting Cisticola, sometimes known as the Streaked Fantail Warbler,Cisticola juncidis, photographed at Serengeti National Park, Tanzania, Africa. [I will identify this bird for you in 48 hours]
Nikon D300, 600 mm VR lens with 1.4 extender ISO 400, f/8, 1/1000 sec.
Please name at least one field mark that supports your identification.
This African mystery bird has the largest range of any of its congeners and its range is expanding northward in Europe. It is difficult to distinguish visually from its congeners where their ranges overlap, but its song is diagnostic.