Iresine diffusa

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Iresine diffusa


Erect to prostrate herb or scrambling vine to 2 m; stems glabrous to sparsely pubescent, frequently with a denser line of hairs at flattened nodes. Petiole 5-45 mm long; blade ovate, lanceolate or elliptical, 3-11 cm long, apex acute to acuminate, base rounded to cuneate, membranous, serrulate with minute ciliolulate teeth, sparsely pubescent above and beneath especially on veins. Inflorescence a diffuse panicle to ca. 45 cm long, comprised of numerous spikes having a "filigree" overall aspect; rachis of spikes very short, 2-3 mm long on ultimate, pubescent in lines; bracts ovate, 0.3-0.6 mm long, hyaline, shining, not keeled; bracteoles 0.5-0.8 mm long, hyaline, not keeled. Flowers unisexual, dioecious (rarely monoecious). Male flowers: tepals ovate to oblong, 0.8-1.3 mm long, stramineous- or white-hyaline, not clearly veined; stamens 5, filaments unequal. Female flowers: tepals oblong, 0.9-1.1 mm long, strongly 3-veined, stramineous- or white-hyaline, enveloped in wavy, white trichomes (lanate) about twice as long as tepals; ovule 1, stigmas 2(-3), linear, curved inwards. Seed lenticular, 0.5-0.6 mm long, reddish-brown, lustrous.


Guyana present, Southern United States present, tropical America present
Southern United States, tropical America; 6 collections studied, all from Guyana (GU: 6).