Iresine grandis Standl.

Iresine grandis Standley, sp. nov
Alternanthera canescens Moq. in DC. Prodr. 13 2 : 351, in part. 1849. Not A. canescens H. B. K. 1817; nor Iresine canescens Humb. & Bonpl. 1805.
Erect shrub, 1.5-3 meters high, sparsely branched, the branches stout, terete, smooth, densely villous-tomentulose or rarely glabrate in age; petioles stout, 1-2 cm. long; leaf-blades broadly ovate-rhombic to broadly ovate, 6-13 cm. long, 3-7 cm. wide, acute or acuminate at the apex, acute or obtuse at the base and short-decurrent, firm, sparsely canescent on the upper surface or glabrate, densely villous-tomentulose beneath, or rarely glabrate; flowers dioecious, loosely paniculate, the terminal panicles pyramidal, usually as broad as long, 1.5-3 dm. long, sparsely leafy below, the branches spreading or ascending; spikelets sessile or pedunculate; bracts and bractlets of the staminate flowers one third as long as the sepals, ovateorbicular, glabrous, the sepals oblong, obtuse or acutish, 2.5-3 mm. long, glabrous, stramineous; filaments equaling the sepals, subulate, the staminodia rhombic or lanceolate, finely dissected into subulate segments; bracts of the pistillate flowers as long as the sepals, round-ovate, whitish, glabrous, the sepals oblong, obtuse, 1.5 mm, long, densely pilose, the hairs white, twice as long as the sepals or shorter; stigmas slender, elongate; utricle oblong, about as long as the sepals; seed 1 mm. long, reddish-brown.
Type collected on limestone ledges, Las Canoas, San Luis Potosi, Mexico, December 5, 1891, C. G. Pringle 3962 (U. S. Nat. Herb. no. 537675). Distribution: San Luis Potosi to Guatemala.