Alkali weed [Greek kressa, Cretan woman, alluding to inhabitant of island of Crete]

Daniel F. Austin†

Perennials or subshrubs, rhizomatous. Stems decumbent to erect, seldom, if ever, mat-forming, glabrate or hirsute to ± sericeous. Leaves petiolate or sessile; blade usually elliptic, lanceolate, ovate, or ovate-lanceolate, sometimes scalelike, 1–10 mm, surfaces glabrous or hirsute to ± sericeous. Inflorescences: flowers usually solitary, sometimes distally clustered, bracteolate. Flowers: sepals elliptic, oblong, obovate, or ovate, 3–6 mm; corolla white [rose], salverform, 5–7 mm, limb 5-lobed, lobes spreading to reflexed, ovate; styles 2, distinct; stigmas capitate. Fruits capsular, ovoid, dehiscence valvate. Seeds 1(–2)[–4], ovoid, glabrous, surfaces smooth or reticulate. x = 14.

Species 4 (2 in the flora): c, w United States, Mexico, South America, Asia, Indian Ocean Islands (Indonesia), Pacific Islands (Hawaii), Australia.

SELECTED REFERENCE Austin, D. F. 2000b. A revision of Cressa L. (Convolvulaceae). Bot. J. Linn. Soc. 133: 27–39.

Lower Taxa

• Cressa nudicaulis Grisebach
• Cressa truxillensis Kunth in A. von Humboldt et al.