Some of the numerous South American representatives of this group are nearly smooth, but the three genera known from Puerto Rico have the trunks, leaf-bases, midribs and inflorescences beset with sharp black spines, and are thus readily recognizable.
Key to the Genera of Bactridinae
Trunk small, cespitose; leaves separated by long internodes; foramina of seeds apical.
Bactris.
Trunk medium or large, solitary; leaves crowded together at the summit; foramina peripheral.
Trunk slender; leaf-divisions broad, praemorse-truncate; pistillate and staminate flowers intermixed on the inflorescence; exocarp fleshy.
Curima.
Trunk robust; leaf-divisions narrow, sharp-pointed; pistillate flowers below and separate from the staminate; exocarp fibrous.
Acrocomia.