Philodendron fragrantissimum (Hook.) G. Don

Ortiz, Orlando Oriel, de Stapf, María Sánchez, Baldini, Riccardo Maria & Croat, Thomas Bernard, 2019, Synopsis of aroids (Alismatales, Araceae) from Cerro Pirre (Darién Province, Panama), Check List 15 (4), pp. 651-689 : 678

Philodendron fragrantissimum (Hook.) G. Don

Material examined. Vicinity Cerro Pirre, along trail from base camp to Rancho Frío on slopes of Cerro Pirre; 07°58′N, 077°43′W; 200–450 m; 27 Jul. 1994; T. B. Croat 77120 ( MO, PMA). Parque Nacional Darién, Cerro Pirre, Rancho Frío; 08°01′14″N, 077°43′41″W; 143 m; 13 Apr. 2016; O. O. Ortiz 2561 ( PMA).

Identification. This species is distinguished by having short internodes, persistent fibrous brown cataphylls, D-shaped petioles in cross section with erect margins, ovate to triangular-ovate blades with a rounded base and inflorescences with spathe tubes bright-red and spathe blades whitish. On Cerro Pirre, juvenile individuals of this species could be confused with those of P. platypetiolatum Madison , which differs mainly in having long internodes and dorsiventrally flattened petioles.

Distribution and ecology. Belize, Brazil, Cuba, Colombia, Costa Rica, Ecuador, Guatemala, Guyana, French Guiana, Honduras, Nicaragua, Panama, Peru, Suriname, and Venezuela. This species of wide distribution is common both in the semideciduous and evergreen forests of Cerro Pirre. Individuals of Philodendron fragrantissimum usually grow in the lower parts of the host trees, between 1 and 5 m. They frequently form large colonies in the same host tree, reaching up to 15 plants simultaneously in the same phorophyte.