Cakile maritima subsp. maritima
Annuals or, rarely, perennials. Stems erect to prostrate, to 8 dm. Cauline leaves: blade broadly ovate to lanceolate, (to 10 cm, smaller distally), margins sinuately lobed or deeply pinnatifid, (distal) often subentire; (lateral lobes 4–8, 5–15 mm). Racemes to 4 dm; rachis straight. Fruiting pedicels 1.5–7 mm. Flowers: sepals 4–5.5 mm, lateral pair not saccate basally; petals usually lavender, rarely white, 8–14 × 3–6 mm, claw distinct. Fruits (often reflexed), hastate, 12–27 × 4–8 mm; proximal segment conical (becoming pedicel-like when aborted, with 2 opposite, lateral horns distally); terminal segment usually 4-angled, mitriform or conic, (margins scarious basally), apex acute or blunt, (usually compressed). Seeds: cotyledons accumbent to, sometimes, incumbent or contorted. 2n = 18.
Phenology: Flowering late spring–fall(-winter if mild).
Habitat: Sandy beaches
Elevation: ca. 0 m
Introduced; B.C., Calif., Md., Oreg., Wash., Europe, introduced also in nw Mexico.
Subspecies maritima is naturalized in Pacific North America (M. G. Barbour and J. E. Rodman 1970); it is also reported on the eastern shores of Chesapeake Bay, Maryland.