Polygala cardiocarpa Kurz, J. Asiat. Soc. Bengal, Pt. 2, Nat. Hist. 41: 293 1872. (syn: Heterosamara birmanica Kuntze; Heterosamara cardiocarpa (Kurz) J. A. R. Paiva; Polygala lacei Craib; Polygala palustris Lace);
Bangladesh to China (S. Yunnan) and Peninsula Malaysia (Langkawi): Bangladesh, China South-Central, Malaya, Myanmar, Thailand, Vietnam as per POWO;
Little yellow flower in Myanmar : 8 posts by 3 authors. 2 images.
Looks close to Corydalis sp. (Papaveraceae). Not sure though!
I think it will be Polygala sp. (Polygalaceae)
May be a species of Polygala or Salomonia
Polygala cardiocarpa Kurz syn : Polygala lacei Craib
While going through the net, I found some images of the stated plant on Facebook. But I found that reddish portion of the flower is missing here.
|30 (29)||Plant branching from upper part of stem, corymbose, branchlets thin; leaf blade ovate-deltoid or ovate; capsule broadly obcordate, ca. 2 mm across; seeds ovoid, tuberculate or punctate, without wings.||25 P. isocarpa|
|+||Plant branching from lower part of stem, branchlets stout; leaf blade ovate; capsule subglobose or subsquare, apex retuse, winged; seeds with appendage||(31)|
|31 (30)||Stem not fleshy; capsule globose or subsquare, ca. 3 mm across; seeds ellipsoidal, exotesta tuberculate, with a black, shiny appendage.||23 P. lacei|
References: POWO Catalogue of Life The Plant List Ver.1.1 IPNI GBIF (High resolution specimens) High resolution specimen High resolution specimen 2 Flora of China FOC illustration Flora Malesiana FPCN Facebook