Philodendron hederaceum var. oxycardium (Schott) Croat, stat. et.
comb. nov. P. oxycardium Schott,
Syn. Aroid. Philodendron scandens subsp. oxycardium (Schott) G. S. Bunting, Gentes Herb. 10: 163. 1968. TYPE: Mexico: exact origin unknown (holotype, W?; lost). Schott ic. 2714 (neotype, W; here designated). [See Fig. 17 in Bunting, 1968].
Internodes smooth, sometimes with 2 ridges or weakly angular on one side, semiglossy, 5--26 cm long, to 1 cm diam., usually longer than broad, drying greenish to pale brownish green; cataphylls 19 cm long, unribbed, green; petioles 8--23 cm long; blades broadly ovate, semiglossy, long-acuminate to abruptly acuminate at apex, cordate at base, 26--32 cm long, 18--22 cm wide (ca. 1.5 times longer than wide), 2.5--3 times longer than petiole, broadest near the middle, upper surface bright green, lower surface yellow-green; sinus narrowly triangular to closed, to 5 cm deep; basal veins 2--3 per side, with 1--2 free to base, and with the first and or second free to base, 2--3 coalesced to 1 cm; primary lateral veins 2--3 per side, departing midrib at a 45E angle. INFLORESCENCES (based on dried specimen) with peduncle 4 cm long, 7 mm diam.; spathe 14 cm long; spathe blade 6.5 cm long; spathe tube 7.5 cm long, spadix sessile, cylindrical, 12 cm long; pistillate portion 4 cm long; staminate portion 8 cm long; fertile staminate portion drying reddish brown.
Flowering in Philodendron hederaceum var. oxycardium is poorly known. A single fertile collection was seen, with immature fruits in January.
Philodendron hederaceum var. oxycardium is apparently endemic to Mexico, known only from the Gulf slope in the states of Jalisco, Nayarit, Oaxaca, San Luis Potosí, and Veracruz at 120 to 580 m principally in areas of Tropical moist forest. Material of P. hederaceum [as P. scandens] collected in Jamaica (Bunting, 1968) is sterile.
Philodendron hederaceum var. oxycardium is similar in appearance to P. hederaceum var. hederaceum, except that leaves of the former are firmer in texture and glossy in both the juvenile and adult forms. In outline, the leaf blades of P. hederaceum var. oxycardium are often somewhat broader and more abruptly acuminate than for P. hederaceum var. hederaceum (Bunting, 1968). The epidermal cells have a more or less flattened epidermis on the upper surface (Bunting, 1968) which causes the surface to be glossy. In contrast, the epidermal cells of P. hederaceum var. hederaceum are mounded and sometimes conical, giving leaves of that variety their characteristic velvety sheen.
Though Bunting (1968) treated this taxon as a subspecies, it appears to overlap geographically with the typical material so it will be treated here as a variety.
Additional specimens examined.
MEXICO. Nayarit: San Blas, Ferris 5440 (DS). OAXACA: Tuxtepec--Oaxaca, 6--14 mi. from bridge at Valle Nacional, ca. 580 m, Moore & Bunting 8905 (BH). San Luis Potosí: N of Tamazunchale, Clark 7408 (MO, NY); Tamazunchale, 120 m, Aguirre & Reko 334 (NY). Veracruz: 5.7--6 mi. from Catemaco on road to Sontecomapan, ca. 380 m, Moore & Bunting 8937 (BH); just before Papantla on road from Tecolutla, Moore & Bunting 8953 (BH); NW of Misantla, 2.4 mi. on road to Martínez de la Torre, ca. 320 m, Moore & Bunting 8944 (BH); Conejo-Huatusco, Km 45, near Puente Nacional, slopes of barranca de Santa María across highway from Hacienda El Mirador, Moore & Bunting 8869 (BH); Dist. Papantla, Kelly 16 (BH).