PHILODENDRON ACUMINATISSIMUM

PROTOLOGUE: Philodendron acuminatissimum , published in Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 26: 543 (1899). The protologue is reproduced below.

DISTRIBUTION: Colombia to Ecuador, Bolivia: Bolivia, Colombia, Ecuador.

DISTRIBUTION NOTE: iNaturalist: Pichincha.

SPECIES DESCRIPTION:

Translated from protologue: Climbing plant with rather long stem internodes about 4 cm long. Cataphylls long-persistent and breaking up into tow-like fibres, about 1.5 dm long. Leaf petiole longer than the blade, terete and rigid, 5–5.5 dm long and 5–6 mm thick; blade rigid and hastate, the posterior lobes slightly exceeding half the length of the anterior lobe, slightly turned upwards, linear-oblong and obtuse, about 2 dm long and 6 cm wide; the anterior lobe linear and very long-acuminate, about 3 dm long and 6–7 cm wide, its acumen 3–4 cm long and scarcely 5 mm wide at the base; primary lateral veins on the upper side 2–3 leaving the posterior ribs, about 5 on each side ascending from the midrib of the anterior lobe.

INFLORESCENCE:

Translated from protologue: Peduncle short. Spathe tube ovoid, shorter than the oblong blade, about 4 cm long and 2 cm wide, the blade 4 cm long. Spadix about 6 cm long, the female zone slightly shorter than the male and about 3 cm long, yellow. Ovaries ovoid and wax-coloured, the locules many-ovuled near the base.

ECOLOGY:

Found in tropical forests, growing as a climber.

ETYMOLOGY:

From Latin acuminatissimus, “most acuminate” or “very long-tapering to a point,” the superlative of acuminatus. Although the original description gives no explanation of the name, it evidently refers to the extraordinarily long, drawn-out apex of the leaf’s anterior lobe, whose slender acumen reaches 3–4 cm and narrows to scarcely 5 mm at the base.

NOTES:

1. Engler cited two collections from Ecuador: tropical forest near San Nicolas (Sodiro 46, in flower September 1892) and near Guayos (A. Sodiro 45). The protologue designates neither as the type.

REFERENCES:

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

2. Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 26: 543 (1899) — protologue.

3. iNaturalist: Philodendron acuminatissimum

Additional photos from iNaturalist by Mark Horton-Sacha, Diego Patino, davidenrique and David Torres