Home
Herbs, annual, to 60[-100] cm tall. Stems branched. Leaves opposite, sessile, linear-lanceolate, 1.6-8 cm × 3[-15] mm, glaucescent, base cordate to auriculate, clasping. Flowers (1-)3-5 in axillary cymes; pedicels ca. 2 mm; peduncle absent to 9 mm; bracteoles reaching floral tube. Floral tube urceolate, 3-5 mm; sepals 4(or 5), broadly deltate; epicalyx segments thickened, ca. as long as sepals. Petals 4(or 5), rose-purple, obovate, ca. 2 mm. Stamens 4(-7), slightly exserted. Style ca. as long as or longer than ovary, well-exserted. Capsules 3.5-5 mm in diam., equal to or exceeding floral tube, rarely included. Fl. Jul-Oct, fr. Aug-Nov. 2n = 66.
Amphidiploid of nos. 1 [Ammannia auriculata Willd.] and 3 [Ammannia robusta Heer & Regel]; stems often freely branched; cymes mostly with 3 or more fls, subsessile or on a short stout peduncle to 4+ mm; pedicels short and stout, or none; hypanthium mostly 2–3.5 mm; pet 1.7–2.5+ mm, deep rose-purple; anthers deep yellow; fr 3.5–4.5 mm thick; 2n=66. N.J. and Pa. to N.D., s. to trop. Amer.; Calif. July–Sept.
