Original paper

A monograph of the genus Aetanthus (Loranthaceae)

Kuijt, Job


The genus Aetanthus is one of two closely related genera of large-flowered neotropical Loranthaceae belonging to Psittacanthinae. In each case, uniquely in the family, endosperm fails to develop, the massive seedling itself providing storage materials needed during germination and establishment on the host. The two genera differ primarily in anther morphology. Psittacanthus has mostly dimorphic, blunt-tipped, dorsifixed, often versatile anthers that are much thicker than the filament, while Aetanthus has essentially isomorphic, basifixed, non-versatile anthers of the same diameter as the filaments and often difficult to distinguish from the latter. The most characteristic feature of the Aetanthus anther is its prominent needle-like connectival terminal extension, essentially unique in Loranthaceae. The present treatment recognizes 15 species, together reaching from central Peru to Andean Venezuela and northern Colombia, all species showing a consistent preference for high elevations. Six new species are introduced (Aetanthus megaphyllus, A. pascoensis, A. prolongatus, A. sessilifolius, A. tachirensis, and A. validus). Keys, full synonymies, descriptions, maps and illustrations are provided for all species.