Psoropodium (Schott) Engl.
in Martius, Fl. Bras. 3(2):138. 1878.
P. grex Psoropodium Schott, Syn. Aroid. 84.1856.
LectoTYPE: P. ornatum Schott (designated by Mayo,1990; page 61).
As defined by Schott, this is a group which has petioles verrucose at apex. Mayo (1991) appropriately selected P. ornatum as the type species. Krause's description "petioles semirounded above, smooth or asperous, blade base cordate or sagittate" would accommodate more than half of the species in the genus Philodendron but Schott's intention for the subsection was clear. The only other species included by Schott was P. rubens Schott, now considered by some authors to be a synonym of P. ornatum. Krause also expanded the group substantially, adding a number of plants which do not have glandular petioles and others that have proven to be synonyms of P. ornatum. The latter include P. muschlerianum K. Krause, P. dolosum Schott, P. asperatum K. Koch, and P. tobagoense Engler. The aberrant elements which, I believe, are unrelated to P. ornatum include P. brevilaminatum Schott and P. trauni (now both synonyms of P. fragrantissimum in P. subsect. Macrolonchium), P. grandipes, and P. maximum K. Krause, a gigantic species from the southwest Amazon basin that is unlikely to be related in any way to P. ornatum. I have moved P. grandipes from P. sect. Psoropodium to P. subsect. Philodendron where it more appropriately belongs.
Krause also included in his Psoropodium group three other poorly known species including, P. thaliaefolium Schott, P. brandtianum K. Krause, and P. bertae K. Krause. These certainly do not appear to be in any way related to P. ornatum. It is clear from these as well as the other species included by Krause that the section as defined by Engler and by Krause no longer resembles Schott's original description. Probably a number of the species will need to be moved into other groups or the section will need to be more well defined. As currently defined no species in P. subsect. Psoropodium occur in Central America.