Shrub or treelet, 1.5 m tall, pubescent or villous, hairs to 0.5 mm long; upper internodes densely glandular. Petiole 0.2-0.5(-1) cm long, vaginate to middle; blade not conspicuously glandular-dotted, lance-elliptic or elliptic-ovate, 8-16.5 x 3-6(-7) cm, margin ciliate, apex long-acuminate, base unequally attached to petiole difference 0-0.2 cm, acute or obtusish, glabrous or pubescent above, (densely) crisp-pubescent or villous beneath; pinnately veined, secondary veins 5-6 per side, originating from lower 3/4 of primary vein. Inflorescence pendent; peduncle 0.5-1.1 cm long, sometimes reddish tinged, crisp-pubescent or villous; spike 1-5 cm long, green to pale or dark yellow, apiculate; rachis glabrous; floral bracts densely marginally fringed; anthers laterally dehiscent. Fruits separate at maturity, depressed globose, 2.5-3(-4) mm in diam., verruculose; stigmas 3, sessile or fruits somewhat stylose.
Guianas: present Southern America:, Venezuela (Venezuela present)
Venezuela and the Guianas; 81 collections studied (GU: 14; SU: 5; FG: 62).
Boni (French Guiana): ampukuwiwii; English (Guyana, Republic of): tona tonakeng; English (Suriname, Republic of): katun uwi
Piper adenandrum and P. avellanum had been considered conspecific by Kramer & Görts-van Rijn (1968: 418). There are, however, several differentiating characters: P. adenandrum has long-acuminate blades, indument of spreading, to 0.5 mm long hairs and distinctly separate fruits, 2.5-3(-4) mm in diam., whereas P. avellanum blades are (short) acuminate or acute, the hairs are crisp, 0.2 mm long, and the fruits 2 mm in diam., not distinctly separate.