Boisduval's Tree Nymph is a butterfly that has a wingspan of up to 4 cm. It is quite common along the eastern regions of South Africa.
It likes areas of coastal or lowland forest. It hangs around the forest edges.
It is attracted to fermenting fruit and on such occasions may be found in large swarms (I think that swarms is the right word?)
Boisduval's Tree Nymph may be seen all year round but is more common in late summer and autumn.
Field Guide to Butterflies of South Africa - Author: Steve Woodhall - Year Published: 2005 - Page: 126
Gardening for Butterflies - Author: Steve Woodhall & Lindsay Gray - Year Published: 2015 - Page: 47
What's That Butterfly - Author: Steve Woodhall - Year Published: 2008 - Page: 752