Lysimachia daphnoides is a small shrub that forms clumps ranging from 20–50 cm in height, with reddish-brown to dark brown bark and several ascending to erect stems. The young stems are densely viscid-hirtellous, eventually becoming glabrate. The leaves are simple, alternate, closely spaced, imbricate, and coriaceous, with oblong-oblanceolate to oblanceolate blades measuring 20–53 mm long and 6–14(–21) mm wide. The leaf apex is acuminate, the base is attenuate, and the surfaces are rusty viscid-hirtellous, particularly near the margins, midrib, and sometimes the base. It bears bisexual, actinomorphic (radially symmetric) flowers that are solitary in the leaf axils, 6–7-merous, with pedicels 15–35 mm long, extending up to 110 mm in fruit, and densely covered in rusty viscid-minute hairs. The calyx comprises 5 sepals with narrowly lanceolate to narrowly ovate lobes, sparsely viscid-hirtellous, and ciliate margins. The corolla is dark purple or burgundy, campanulate, 15–20 mm long, with obovate lobes. The stamens are as many as and opposite the corolla lobes, with filaments connate in the lower third and anthers dithecal. The fruit is a subglobose, regularly dehiscent capsule with dark brown, irregularly shaped, approximately 2 mm long seeds with a crustaceous seed coat. It is typically found in vegetation islands within swamps and bogs between 1,220 – 1,570 meters.