Hypericum species- Sri Lanka

BND 105 27/11/14 : 3 posts by 3 authors. Attachments (1)
Please ID this small herbaceous plant with yellow flowers. Photo was taken in Sri Lanka in Mar 2012. 
Hypericum sp. i suppose.
Hypericum oblongifolium.
Not Hypericum oblongifolium as I think not found there. May be some other species. But more details are required.