This species is rather commonly collected and is characterized by its robust habit, well developed triangular stipules with markedly lacerate margins, stiff-textured often rugose leaves, shortly pedunculate, shortly cymose inflorescences with the flowers subsessile in groups, rather large yellow to red fruits, and quite long corollas. The corolla tubes are 50-80 mm long. Rudgea lanceifolia as circumscribed by Zappi (2004) ranges across the Amazon basin and has some variation in leaf and inflorescence size.

Rudgea lanceifolia is similar to Rudgea longiflora, Rudgea viburnoides, and Rudgea viburnoides megalocarpa. Prolonged corolla tubes are also found in Rudgea graciliflora and several species that are similar to that. Before the studies by Zappi, Rudgea lanceifolia was most often identified with the name Rudgea fissistipula, which is a synonym. Plants from southern Venezuela described as Rudgea sipapoensis are rather distinctive in their smoother leaves that dry yellowed or green; these plants were included within Rudgea lanceifolia by Zappi (2004), and their status cannot be further evaluated until flowers of this form are documented. Plants from La Macarena in southeastern Colombia that were identified in sched. as Rudgea viburnoides subsp. megalocarpa are here included provisionally in Rudgea lanceifolia; no mature flowers or fruits have been seen for these, however they match vegetatively in general although the leaves are on average somewhat smaller.