PHILODENDRON ALTOMACAENSE

PROTOLOGUE: Philodendron altomacaense , published in Boletim de Botánica, Departamento de Botánica, Instituto de Biociencias, Universidade de São Paulo 17: 48 (1998).

Philodendron altomacaense Nadruz & Mayo, sp. nov.

Philodendron apparicioi G.M. Barroso affine sed nervis lateralibus primarias pluribus, loculis ovarii paucioribus, margine laminae folii integro, petiolo spathaque immaculatis, spadice zona sterili apicali instructa differt.

Typus: Brasil, Rio de Janeiro, Nova Friburgo, Macaé de Cima, Sítio Sophronitis, estrada principal, M. Nadruz 779 et al., 03.XI.92 (holotypus RB, isotypus K).

DISTRIBUTION: Brazil (Rio de Janeiro): Brazil Southeast.

DISTRIBUTION NOTE: iNaturalist: Rio de Janeiro.

SPECIES DESCRIPTION:

Translated from protologue: Stem cylindrical, 4.0–7.0 cm in diameter, green when young, becoming brown later; internodes (1–)4.0–5.0 cm long. Adventitious roots red when new, with a yellowish apex, the older ones 6.0 mm in diameter. Cataphyll ca. 30 cm long, 1.5 cm wide, fleshy, reddish, becoming brown later, deciduous, pronouncedly bicarinate. Petiole flattened on the adaxial face with the margins slightly carinate, 48.0–69.5 cm long, 1.7 cm in diameter, green in the proximal-middle portion and reddish at the apex, matte, with striations concolorous to slightly darker. Sheath green, 5.0 cm long, in the adult flowering sympodial unit. Blade chartaceous, elliptic-cordate, (37.0–)45.0–47.5 cm long, (20.0–)26.0–27.0(–34.0) cm wide, bright dark green on the adaxial face and matte on the abaxial face, margin entire, yellowish-green or purplish. Anterior division 26.5–37.0 cm long, 16.0–24.5(–31.0) cm wide, apex acute and slightly cuspidate. Midrib impressed on the adaxial face and prominent on the abaxial face, green, paler than the blade on the adaxial face and greenish-red to red on the abaxial face. Primary lateral veins 6–7(–9) pairs, impressed on the adaxial face and prominent on the abaxial face, concolorous to paler than the blade or greenish-red and matte on the abaxial face, frequently with reddish tinges. Interprimary veins impressed on the adaxial face and well developed on the abaxial face. Posterior division (8.0–)12.0–18.0 cm long, (14.2–)18.0–29.0(–36.4) cm wide, lobes retrorse, overlapping or nearly so, posterior rib naked for 2.0–3.5 cm, acroscopic primary veins 0–1(2) and basioscopic primary veins 2–3. Sinus parabolic-spatulate.

INFLORESCENCE:

Translated from protologue: Floral sympodium with up to 3 inflorescences. Peduncle 4.5 cm long, 1.1–1.2 cm in diameter at the apex, green, becoming carmine at the apex. Spathe 12.0–19.0 cm long, 1.6–2.3 cm wide in the median portion, without differentiation between tube and blade, cylindrical, cuspidate at the apex, decurrent for 4.5–5.3 cm, externally cream-greenish to greenish-red with a reddish band on the dorsal side from the base to almost the apex, internally cream with the lower half carmine, with paler dots. Spadix 13.0–17.0 cm long, sessile, with ferruginous resin canals in the axis below the staminate flowers; apical sterile staminate zone cream, 0.8–0.9 cm long, 0.6 cm in diameter, fertile staminate zone cream, 6.0–7.9 cm long, 1.5 cm in diameter, basal sterile staminate zone cream, 1.3–1.5 cm long, 1.5 cm in diameter, pistillate zone green, 5.8–6.8 cm long, 1.6 cm wide, conspicuously adnate to the spathe for 4.3 cm. Stamens 4–5, 2.0–2.5 mm long, 1.2–1.8 mm wide at the apex, slightly attenuate towards the base. Staminodes ca. 2.0 mm long, 2.0–2.5 mm wide at the apex, attenuate towards the base. Gynoecium 4.5 mm long, 1.8 mm wide in the median region, oblong-obovate, ovary white, locules (7–)8–10, ovules 2–3 per locule, 0.7 mm long, placentation sub-basal, with trichomes on the funicles. Mature infructescence 8.8–10.0 cm long, 1.7–2.2 cm in diameter, berries cylindric-obovate, greenish to cream, 0.6–0.7 cm long, 0.35–0.40 cm wide, stigma persistent; seeds greenish, numerous, grouped in pairs, cylindric-ellipsoid, ca. 1.5 mm long, 0.8 mm wide.

ECOLOGY:

Found in humid, shaded montane Atlantic rainforest above 1000 m, growing as a scandent hemi-epiphyte to creeping terrestrial.

ETYMOLOGY:

Although the original description does not explicitly explain the name, the epithet altomacaense evidently refers to Macaé de Cima (Alto Macaé, “Upper Macaé”), the highland district of Nova Friburgo in Rio de Janeiro state, Brazil, where the species grows and to which it appears to be endemic. The Latinized suffix-ense denotes place of origin.

NOTES:

1. Characterized, among other features, by the large number of primary lateral and interprimary veins. A species very close to Philodendron apparicioi Barroso, from which it differs in its unmarked petiole and spathe, entire leaf-blade margin, 6–7(–9) pairs of primary lateral veins (against 5 in Philodendron apparicioi, Barroso 1957), a sterile apical zone on the spadix, and a smaller number of locules in the ovary.

2. Frequent in the area and, as far as is known, endemic to the Macaé de Cima region. It is of considerable ornamental value on account of the coloration and gloss of its large leaves.

3. Under the IUCN criteria (Carauta 1989), the species was assessed as endangered; although it occurs within a conservation unit, it is poorly protected and grows in a restricted area.

STORY:

STORY TITLE: A large-leaved Philodendron endemic to Macaé de Cima

When Marcus Nadruz Coelho and Simon Mayo described five new species of Philodendron from Brazil in 1998, three of them proved to be endemic to the state of Rio de Janeiro. Philodendron altomacaense is one of these, its name pointing to Macaé de Cima — the highland district of Nova Friburgo where every known collection has been made.²

The plant was gathered repeatedly between 1989 and 1993 in the area of the Projeto Mata Atlântica (Atlantic Forest Project), along the main road of the Sítio Sophronitis and the trail to the Pedra Bicuda, at elevations above 1000 meters. It grows as a scandent hemi-epiphyte that also creeps over the ground in very humid, shaded forest, and its large, glossy, dark green leaves give it real ornamental appeal.²

Frequent though it is within that small area, the species appears to occur nowhere else. Coelho and Mayo considered it endangered: poorly protected even inside a conservation unit, and confined to a restricted range.²

REFERENCES:

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

2. Boletim de Botánica, Departamento de Botánica, Instituto de Biociencias, Universidade de São Paulo 17: 48 (1998) — protologue.

3. iNaturalist: Philodendron altomacaense

Additional photos from iNaturalist by Lucas Tonoli, Marcos Mortara, Marco Pellegrini, bettinadungs and luizhenriquemacedo