This species is closely allied to *Ludwigia hyssopifolia* (G. Don) Exell., having only petals. But your specimen with 5 lobes. *Ludwigia hyssopifolia: *Herbs; branchlets angled or winged. Leaves 2.5-5 x 1-2 cm, elliptic-lanceolate, base cuneate, apex gradually acute to acuminate, glabrous, membranous; petiole to 1 cm long. Flowers solitary, axillary. Calyx tube narrow; lobes 4, c. 3 mm long, lanceolate, persistent. Petals 4, obovate, yellow. Stamens 8; filaments unequal. Ovary 4-celled; ovules many; stigma 4-lobed. Capsule c. 2 cm long, linear, terete, 8-ribbed. Seeds dimorphic, uniseriate and embedded in endocarp below and pluriseriate and free above. Please compare with this species.
-- *Prabhu Kumar K M* Scientist Plant Systematics & Genetic Resources Division Centre for Medicinal Plants Research (CMPR) & 'CMPR' Herbarium Kottakkal Arya Vaidya Sala Kottakkal, Malappuram *E-mail: [email protected]* --
