This species is characterized by its hirtellous pubescence at least on parts of the lower leaf surface, medium-sized obovate leaves, stipules 5-7 mm long, subsessile flowers, calyx lobes ca. 1 mm long, corollas ca. 3 mm long, and capsules 8-15 x 2-3 mm. Alseis eggersii appears to be locally quite common in northeastern Peru. 

This species is here limited to include only populations from the Pacific slopes of the region. This region has a number of species restricted to this biogeographic zone. The name Alseis eggersii has also been applied to plants from the Amazon drainage also, but those were excluded by Andersson (in Andersson & Taylor, 1994) and are excluded here. Alseis eggersii is similar to Alseis peruviana, described from the Amazon basin in northern Peru, and these are both known mainly from sterile specimens and old fruits and are separated here based mainly on geography; this corresponds to some extent also to habitat, with the Amazonian plants known mainly from the more humid Río Huallaga drainage.