Philodendron inaequilaterum Liebm.

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 : 679

Philodendron inaequilaterum Liebm.

Material examined. Parque Nacional Darién, vicin- ity of Cerro Pirre base camp, along trail near E side of Río Paracida; 08°00′N, 077°48′W; 0–80 m; 1 Jul. 1988; T. B. Croat 68967 ( MO). Parque Nacional Darién, Cerro Pirre, Rancho Frío; 08°01′16″N, 077°44′04″W; 103 m; 13 Apr. 2016; O. O. Ortiz 2537 ( PMA). Ibid.; O. O. Ortiz 2539 ( PMA). Ibid.; O. O. Ortiz 2551 ( PMA). Ibid.; O. O. Ortiz 2552 ( PMA).

Identification. This species is recognized by its nomadic vine life form (appressed-climbing habit), chartaceous blades with numerous primary lateral veins, inequilat- eral at base, paired inflorescences with slender spadices and orange berries. Grayum (2003) mentioned that this species is very similar to P. rayanum Croat & Grayum (also present on Cerro Pirre), but the latter differs in hav- ing narrower blades and thicker spadices with a longer female portion.

Distribution and ecology. Belize, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, and Venezuela. Philodendron inaequilaterum ocurrs in the semideciduous and evergreen forests of Cerro Pirre, between 90 and 800 m. This species is probably the most abundant of the semideciduous lowland forests of Cerro Pirre. Its spatial distribution appears to be irregular, usually growing in large colonies, both in wooded areas and on open trails and along the banks of rivers and streams.