Shrub to 2.5 m tall. Stem glabrous, young ones often reddish. Petiole 0.4-0.8 cm long, glabrous, pubescent when young, vaginate at base; blade shiny dark green above, pale below, densely black glandular-dotted, translucent dotted in vivo, (narrowly) ovate to elliptic-oblong, 8-15 x 3-6 cm, apex acuminate, base equal or almost equally attached to petiole, acute or cuneate or obtusish, occasionally rough above (from scale-like emergent structures), glabrous below; pinnately veined, secondary veins 3-5 per side, anastomosing near margin, originating from lower 3/4 of primary vein, tertiary veins widely reticulate, not conspicuous. Inflorescence pendent; peduncle slender, 0.5-1.8 cm long, glabrous, often reddish or violaceous; spike 1-5 cm long, 10 mm in diam. in vivo, green, yellow to reddish, apiculate; floral bracts densely marginally fringed. Infructescence pendent, green; fruits trigonous or subtetragonous with narrow “collar”, glabrous, green, stigmas 3, sessile.
Amazonian Bolivia: present French Guiana: present Guianas: present NE Brazil: present
NE Brazil and the Guianas (mainly French Guiana) and Amazonian Bolivia; over 120 collections studied (GU: 6; SU: 1; FG: 114).
Many collections were previously assigned to Piper rudgeanum. After having compared those collections with the type of P. rudgeanum (Suriname, Kegel s.n.), it is certain that they belong to P. nigrispicum. Piper rudgeanum differs in having 1 cm long spikes on stout peduncles, stylose ovaries and fruits subtended by cucullate floral bracts with only the ventral margin fringed, whereas in P. nigrispicum slender peduncles bear 1-5 cm long spikes and the ovaries and fruits have sessile stigmas and are subtended by densely marginally fringed floral bracts.