Phrymaceae

Plants in this family are highly diverse in life history and structure, and have been extensively studied as models to better understand evolution and ancestral relationships. Non-woody (herbaceous) perennials with stems that are often square in cross section, and opposite leaves with toothed edges.

Flowers bilaterally symmetrical, each flower producing both pollen and seeds. Flowers solitary, on stalks, showy, yellow or blue (rarely pink or white); or tiny, pink or white, paired in long spike-like racemes at top of stem and arising from leaf axils. Sepals 5, fused at base to form a tube with 5 separate lobes or teeth at top. Petals 5, fused to form a tube at base and 2 lips at top, the upper lip with 2 lobes, the lower with 3. Stamens 4. Carpels 2, fused to form 1 pistil; ovary located above point of attachment of other flower parts (superior); style 1, long; stigma with two flattened plates or lobes that only receive pollen on the inner surface, closing together upon contact with their insect pollinators (to help prevent self-pollination).

Fruit in most species a capsule containing many seeds. Fruit in Lopseed is an achene (only 1 of the 2 carpels remains fertile to produce this); as the paired flowers of Lopseed wilt and develop into achenes, they droop downward and rest against the stalk of the raceme.