Water Pigmy-weed - Tillaea aquatica
State Rank Reason (see State Rank above)
Collected in Sanders County. Status in the state unresolved.
Small glabrous annual. Stems prostrate to ascending, branched, 1–4 cm. Leaves all cauline, opposite, linear, terete, 3–6 mm long, united around the stem. Flowers solitary in leaf axils, 4-merous, calyx up to 1 mm long; petals white, 1–2 mm long. Follicles 1–1.5 mm long, erect, deep red; seeds 1 to few per follicle (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX)