PHILODENDRON CORIACEUM

PROTOLOGUE: Philodendron coriaceum , published in Novon 18: 433 (2008).

Philodendron coriaceum Croat & D. C. Bay, sp. nov.

Planta hemiepiphytica aut terrestris, scandens; internodia 1.5–13.5 cm longa, 4–8 mm diam.; cataphylla 15–18.5 cm longa, decidua intacta. Folia erecta; petiolus 6–11 cm longus, 3–5 mm diam. in sicco, D-formis vel late sulcatus; lamina ovata, coriacea, nervis lateralibus primariis 13 ad 18 utroque. Inflorescentia solitaria; pedunculus 3–5 cm longus; spatha 10.4–18 cm longa, lamina utrinque pallide viridi, tubo extus virenti interdum suffuso roseo, intus rubroviolaceo. Pistilla ca. 8 × 7–10 mm; ovarium 6- ad 9-loculare, loculis 2- ad 3-ovulatis.

Type: Colombia. Valle: Bajo Calima region, Buenaventura–Málaga rd., vic. of Km 50.7, less than 100 m, 12 July 1993, T. B. Croat & D. C. Bay 75696 (holotype, MO-04575796; isotypes, B, COL, CUVC, F, K, NY, PMA, US).

DISTRIBUTION: Colombia to Ecuador: Colombia, Ecuador.

SPECIES DESCRIPTION:

Hemiepiphytic or terrestrial, trailing over the ground; stems appressed-climbing or scandent; internodes semi-glossy, 1.5–13.5 cm × 4–8 mm, longer than broad, medium or dark green to purplish brown, drying golden to red or rusty brown with wrinkled, sometimes flaky epidermis; roots usually 2 per node, sometimes highly branching, red-brown; cataphylls 15–18.5 cm, unribbed or bluntly 2-ribbed, D-shaped in cross section with a bluntly rounded apex, light green to yellowish green, often tinged red, drying pale reddish tan and wrinkled, deciduous. Leaves erect; petioles 6–11 cm × 3–5 mm (dry), D-shaped to broadly sulcate, medium green, tinged red, semiglossy, drying yellow-green, somewhat red with a loose, wrinkled epidermis; blades ovate, thick and coriaceous, obtusely acuminate at the apex, obtuse at base, 12–21 × 5–12 cm, 1.6–2.3(–2.6) times longer than wide, (1.3–)2–2.5(–3.2) times longer than petiole; adaxial surface glossy, dark green, drying glossy, green or olive-green, abaxial surface paler, drying glossy and paler than adaxially; midrib flat and pale yellow-white adaxially, round-raised, paler than the blade and tinged red abaxially; primary lateral veins etched adaxially, darker abaxially, 13 to 18 per side and very close together (ca. 1 cm apart), departing the midrib at 30–40° angles, drying concolorous and raised on both sides; cross veins numerous, minute, perpendicular, weakly etched adaxially, scarcely visible abaxially, drying concolorous and wrinkled on both sides.

INFLORESCENCE:

Inflorescences erect, 1 per axil; peduncle 3–5 cm × 3–8 mm (dry), much shorter than the petiole, green, drying reddish olive; spathe semiglossy, thin and long-tapered, 10.4–18 cm, drying red-brown; spathe blade pale green outside and inside; spathe tube medium green sometimes tinged rose outside, red-violet inside, with reddish orange resin canals inside the tube; spadix long-tapered, white, 8–15.5 cm; pistillate portion 1.6–2.1 cm long on the back, 2.3–6.5 cm long on the front, 8–18 mm diam. (dry); staminate portion 5.7–9.7 cm × 6–10 mm from base to ca. 1 cm from the apex where it begins to gradually taper (dry), narrower than the pistillate portion, wider than the sterile staminate portion; sterile staminate portion 0.5–1 cm × 5–7 mm throughout (dry), narrower than the pistillate or fertile staminate portions; pistils ca. 8 × 7–10 mm; ovary 6- to 9-locular, ovules with subbasal placentation, 2 to 3 per locule. Infructescences with pistillate spadix 8–9 cm, berries globular, yellow-orange with red-brown stigmas.

ECOLOGY:

Found in Colombia (Chocó and Valle departments), from Tropical wet forest to Tropical rain forest transition to Premontane forest, near sea level to 150 m, and in Carchi and Esmeraldas provinces, Ecuador, in Tropical wet montane forest from near sea level to 800 m.

ETYMOLOGY:

From Latin “coriaceus,” meaning leathery or of leather, referring to the thick, coriaceous texture of this species' leaf blades, singled out in the protologue as one of its most distinctive characters.

NOTES:

1. This species is a member of subgenus Philodendron, section Macrobelium, subsection Macrobelium. It would key to series Ecordata Croat, but may represent a new series because the blades lack etched minor veins on the adaxial surface. The species is characterized by its scandent habit; thick, ovate, coriaceous blades with a flat midrib much paler than the blade adaxially and often tinged red abaxially; and yellow-orange berries.

2. Philodendron coriaceum is most easily confused with Philodendron chrysocarpum, which has elliptic leaves and yellow-orange berries. However, Philodendron chrysocarpum differs in having subcoriaceous blades 3.4–4.8(–5.2) times longer than broad (in contrast to 1.6–2.3(–2.6) times longer in Philodendron coriaceum), a broadly raised midrib that is slightly paler adaxially and much paler or purple abaxially, and a yellowish green-striate spathe (in contrast to a spathe that is red-violet on the tube in Philodendron coriaceum).

REFERENCES:

1. Plants of the World Online, Royal Botanic Gardens, Kew — Philodendron coriaceum

2. Novon 18: 433 (2008) — protologue.