Philodendron tuerckheimii Grayum

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 : 683

Philodendron tuerckheimii Grayum ( Fig. 7C)

Material examined. Middle slopes on W side of Cerro Pirre; 07°56′N, 077°45′W; 800–1050 m; 29 Jun. 1988; T. B. Croat 68920 ( MO). Parque Nacional Darién, Serranía de Pirre, Rancho Plástico; 07°58′54″N, 077°42′30″W; 1128 m; 31 Jul. 2016; O. O. Ortiz 2654 ( MO, PMA). Ibid., campamento cerca del segundo mirador; 07°59′43″N, 077°42′39″W; 708 m; 2 Dec. 2016; O. O. Ortiz 2703 ( PMA).

Identification. This species is characterized by its nomadic vine life form (ramified habit), short petioles (50% of the length of the lamina) with horizontally splayed petiole sheaths, reddish brown small blades (when dry) with few primary lateral veins (five to seven per side) and solitary inflorescences with a relatively long female portion. According to the observations made in the field, the specimens of Philodendron tuerckheimii collected on Cerro Pirre have unusual coriaceous blades. Grayum (1996) documented this variation and stated that the specimens of Cerro Pirre are characterized by having larger petioles with the unsheathed portion of the petiole relatively long (up to 0.8 cm) and comparatively larger blades. Probably, the populations of Cerro Pirre correspond to a new taxon, but it is necessary to document in detail the morphological variations of these populations and to carry out additional collections.

Distribution and ecology. Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, and Venezuela. According to the samplings, P. tuerckheimii ocurrs in the evergreen, submontane, and montane forests of Cerro Pirre; but it is more frequent throughout the montane cloud forest, located above 1100 m.