Monstera siltepecana Matuda

Juvenile: terrestrial creeper, internodes 1 – 3 cm long, leaves exserted and erect, lamina ovate to widely ovate, cordate at the base, acuminate or acute, membranaceous, unequal with one side 1.1 to 2.0 times wider than the other. Adult stem: subterete, smooth, in climbing shoots 2.0 – 3.5 cm thick, internodes 4 – 8 cm long; in stolons 1 – 2 cm thick with internodes 20 – 30 cm long; leaf scars narrow, the ends of each joining in the back of the stem; axillary buds lanceolate to ovate, acuminate, in a depression in the stem not extended into a sulcus. Petiole: 30 – 45 cm long, about equal in length to the lamina, vaginate to the geniculum, the wings neatly deciduous, the geniculum 3.0 – 4.5 cm long. Lamina: subcoriaceous, ovate, unequal, sometimes falcate or the midrib curved, 30 – 60 cm long, 20 – 35 cm wide, broadly cordate at the base, the tip acuminate; margins entire, perforations mostly numerous in 2 to 4 series on each side of the midrib, round near the midrib, elongate near the margin (rarely perforations only one or two); the primary lateral veins parallel, 8 – 12 in number, secondary lateral veins reticulate. Peduncle: smooth, green, terete, 8 – 20 mm thick, 5 – 12 cm long. Spathe: thickly coriaceous, greenish-white outside, rose-colored within, 18 – 25 cm long, 15 – 20 cm around, cuspidate. Flowering spadix: white, cylindric, 10 – 13 cm long, 3.0 – 3.5 cm thick; flowers near the base sterile, the fertile pistils prismatic; stigma round, sessile. Fruiting spadix: deep green, cylindric, 12 – 17 cm long, 4.5 – 6.0 cm thick, the berries mostly one-seeded; seeds light brown, 6 – 7 mm long, 3 – 5 mm wide, 2 – 3 mm thick.

Madison 1977: 56 - 57.