Large herb to 3 m tall. Internodes black glandular-dotted, more densely so on nodes. Leaves alternate, peltate; petiole attached at up to 1/3 of blade, rarely near base, 8-20 cm long, vaginate or slightly winged in lower part; blade glandular-dotted, round-ovate, to 16-30 x 18-40 cm, apex acute, base nearly rounded to usually deeply cordate, glabrous except for short hairs on veins; palmately 13-15-veined, veins radiating from petiole tip, and 2 pairs originating from central vein. Inflorescence erect, umbellate, seem to be axillary, but are reduced, sympodial branches with very short internodes, without leaves; common peduncle 2-8 cm long, peduncles slender, 1-1.5 cm long; spikes numerous, 5-10 cm long, each subtended by a single prophyll, densely flowered; floral bracts marginally fringed. Fruits trigonous, glabrous.
tropical S America present
Widely distributed in tropical S America; ca. 60 collections studied (GU: 25; SU: 13; FG: 25).
There has been quite a discussion on the correct name of the taxon. I agree with R. Callejas that the taxon can best be placed in Piper, not separated as Lepianthes or Pothomorphe. Piper peltatum together with P. marginatum, P. umbellatum L. and several other extra-Guianan taxa form a distinct clade within Piper (Jaramillo & Manos, Amer. J. Bot. 88: 712. 2001). They do not form a monophyletic group and should not be separated from Piper.