32. Physaria (Nutt.) A. Gray (bladderpod)

Plants annual or biennial (perennial elsewhere), terrestrial, with sessile, stellate hairs. Stems ascending from a spreading base to erect (creeping elsewhere), usually few- to several-branched from the base. Leaves alternate and basal, the basal leaves usually with petioles, the upper leaves usually narrower and short-petiolate or sessile, the bases not clasping. Inflorescences racemes, the flowers bractless. Sepals mostly ascending. Petals unlobed, yellow (white to light purple elsewhere), without conspicuously darkened veins. Styles 2–5 mm long. Fruits with the body about as long as wide or less than 2 times as long as wide, usually spreading, globose or broadly ellipsoid to obovoid or pear-shaped, not flattened (flattened elsewhere), the slender style often persistent. Seeds in 2 rows in each locule, 1.6–2.2 mm long, circular in outline or nearly so, slightly flattened, the margins rounded, not winged, the surface minutely roughened, reddish brown (variously sized, shaped, or winged elsewhere). About 105 species, North America, South America, eastern Asia (1 species).

Extensive molecular studies (summarized in O’Kane and Al-Shehbaz, 2002a, b) have indicated that species ascribed to Physaria as traditionally circumscribed evolved more than once from different lineages within Lesquerella S. Watson. Attempts to conserve Lesquerella, the much larger but more recently published genus, against Physaria (O’Kane et al., 1999) did not succeed, and when the two genera are united (O’Kane and Al-Shehbaz, 2002a) the resultant larger group must be called Physaria.