PLANT: Annual herbs from a taproot. STEMS: prostrate to somewhat ascending with radially spreading branches, 4-25 cm long or more often reddish, glabrous. LEAVES: alternate, flat, ovate-cuneate or spatulate, 10-17 mm long, 5-12 mm wide; nodes with a few inconspicuous hairs in the axils. INFLORESCENCE: glabrous or with a few inconspicuous hairs; involucral leaves 1-4, 6-20 mm long, 2-8 mm wide. FLOWERS: solitary or clustered at the ends of branches; petals yellowish, 2-5 mm long; stigmatic branches 3-6. CAPSULE: 2-6 mm in diameter; slightly stipitate. SEEDS: black, finely granulate, stellate, or rounded-tuberculate. NOTES: Disturbed areas, especially roadsides: reported from all AZ cos. except LaPaz; 450 – 2400 m (1400 – 7800 ft); Jun–Oct. Introduced. Worldwide in temperate to warm regions; throughout the U.S. (including AK) and Canada. Young leaves and stems edible raw or cooked. Portulaca retusa has been previously recognized as a separate species, based on seed morphological characteristics, growth habit, sepal shape, and number of stigmatic branches (Correll & Johnston 1970, W.B. McDougall 1973, Martin & Hutchins 2001, Kearney & Peebles 1960, Welsh et. al. 2003). Positive identification from herbarium specimens is only possible with mature seeds (roundedtuberculate vs. sharply echinate or stellate in P. retusa). Intergradation of seed morphological characteristics between the two species has also been observed. Other characteristics such as growth habit, sepal shape, and number of style lobes, previously thought to distinguish P. retusa from P. oleracea, have been found highly variable (Correll & Johnston 1970, Martin & Hutchins 2001, Kearney & Peebles 1960, Welsh et. al. 2003, W.B. McDougall 1973). More work, especially with fresh intact specimens, is needed to substantiate recognition of P. retusa at the specific level. REFERENCE: Allison Bair, Marissa Howe, Daniela Roth, Robin Taylor, Tina Ayers, and Robert W. Kiger., 2006, Vascular Plants of Arizona: Portulacaceae. CANOTIA 2(1): 1-22.