Monstera spruceana Engler 1878
Creators: name: Croat, Thomas B.
name: Cedeño-Fonseca, Marco
name: Ortiz, Orlando O.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Alismatales
Araceae
Monstera
Monstera spruceana

description: 44. Monstera spruceana (Schott) Engl. in Martius, Fl. Bras. 3(2): 115. 1878.
— Tornelia spruceana Schott, Oesterr. Bot. Z. 9(2): 40. 1859. (Figs. 75, 76)
Type: — BRAZIL. [Amazonas:] Rio Negro, São Gabriel, [1852?], R. Spruce 2293 (holotype K! two sheets: K000434532 & K000434533).
Robust nomadic vine, appressed-climbing habit. SEEDLINGS: filiform. JUVENILE PLANTS: root climbers; stems dark green, smooth, cylindrical; internodes 2–8 cm long, 0.5–12.0 mm diam.; petiole not visible, dark green, smooth, 4–6 cm long; blades obovate, subcordate at base, acuminate at apex, coriaceous, 5–15 × 6–12 cm, appressed to the phorophyte; fenestrations present, usually 1 that breaks at the margin.ADULT PLANTS: root climbers; stems light or dark-green, cylindrical, warty with pustules; internodes 3–8 cm long, 2–6 cm diam., 1.3–1.5 times longer than wide; anchor roots light brown; feeder roots dark brown with white trichomes; petiole light-green, smooth or warty, 25–50 cm long, sheathed to base of the geniculum or to base of the blade; petiole sheath deciduous with fibrous fragments; geniculum smooth or warty, sunken adaxially, convex abaxially, 2–4 cm long; blades lanceolate or ovate, obtuse, truncate, subcordate or attenuate at base, obtuse to slightly acuminate at apex, coriaceous, drying grayish or blackish, 25–60 × 25–30 cm, 1.2–2.2(3.3) times longer than wide, decurrent on the geniculum, decurrent portion 3–4 mm wide; midrib ribbed adaxially, convex abaxially, drying black to dark brown on both surfaces; primary lateral veins 10–18 per side, sunken adaxially, prominent abaxially, drying blackish or dark brown; collective veins not visible; fenestrations present in transition to adult plants; margins pinnatilobed, 1–6 lobes per side, 2–4 veins per lobe. INFLORESCENCES on ascending stems, 1 or 2 simultaneously at flowering time, arranged in the axils of the leaves; peduncle smooth, 4–10 cm long; spathe obtuse to short-acuminate, white internally and light green externally during development, unknown at anthesis; spadix white during development, unknown at anthesis, 15–25 cm long, 3–6 cm diam., 8–9 times longer than wide; basal sterile flowers 5–7 mm long; fertile flowers 6–8 mm long; stamens 2–7 mm long, with laminar filaments; anthers 1.5–2.0 mm long; ovary rectangular in longitudinal section, ribbed, rectangular, more slender than style, 3–4 × 2–3 mm; style hexagonal, 3–5 × 3–4 mm, stigma linear; berries with a green stylar cap during development, mature stylar cap unknown; pulp unknown; seeds unknown.
Distribution and ecology: — Monstera spruceana ranges from Costa Rica and Panama to Colombia, Venezuela, the Guianas, Venezuela, Brazil, Ecuador, Peru and Bolivia, at 50–1600 m, in Premontane wet forest and Premontane rain forest life zones.
Phenology: —Flowering in April and October. Fruiting in December.
Discussion: —The species is a member of sect. Marcgraviopsis. It is distinguished by its pinnatilobed adult leaf blade with relatively broad pinnae with divisions extending to very near the midrib, the slightly verrucose or smooth petiole, sheathed up to the base of the geniculum or even up to the base of the blade, the petiolar sheath disintegrating as fibrous residues, short peduncles (<10 cm), long spadices (15–25 cm), and dark green stylar caps after anthesis. Other distinguishing features include the usually grayish to sometimes blackish drying blades.
It is similar to Monstera anomala, but that species is distinguished by its completely entire leaves, by the constricted stylar region, and by its occurrence (at least in Costa Rica and Panama) in lowland humid forests (Cedeño-Fonseca et al. 2022).
Additional specimens examined: — COSTA RICA. Alajuela: Uapala, Slope of cerro Cacao, E to near Río Las Haciendas, 1150 m, 14 August 2007, (Infer.), M.H. Grayum 12713 (MO!); Puntarenas: Puntarenas, Monteverde, Camino a Tilaran, 1325 m, 21 November 2018, (Fr.), M. Cedeño & A. Cascante 1501 (USJ!); Puntarenas, Osa, Bahía Drake, Camino a Rancho Quemado, 188 m, 3 February 2019, (Infer.), M. Cedeño, A. Hay 1621 (USJ!); Osa, Sierpe, Along road between Rincon and Boscosa, 2 Km W of bridge over Rio Rincon, 50 m, 11 September 1996, (Fr.), T.B. Croat 79253 (CR!, MO!). PANAMA. Chiriquí: Vicinity of Fortuna Dam site on Río Chiriqui beyond Gualaca 9.4 mi beyond Gate to Francisco Linare’s house, 20.9 mi from bridge over Río Estí, 10.8 mi beyond Los Planes de Hornito, 1400 m, 27 November 1979, T.B. Croat 48709 (MO!); Vicinity of Fortuna Dam site on Río Chiriqui beyond Gualaca 9.4 mi beyond Gate to Francisco Linare’s house, 20.9 mi from bridge over Río Estí, 10.8 mi beyond Los Planes de Hornito, 08°42’N 082°14’W, 1400 m, 27 Nov 1979, T.B. Croat 48713A (MO!); Colón: Santa Rita Ridge, 5.7 mi from Boyd-Roosevelt Hwy, along road which turns to left off main route, 0.2 mi from jct., 09°21’N 079°44’W, 250 m, 17 July 1994, T.B. Croat & G. Zhu 76970 (CM, MO); Donoso. Minera Panamá copper-mining concession, slopes and ridges S of Río Botija (along trail to harpy eagle nest), 08°48’55”N 080°39’04”W, 205 m, 27 August 2014, M.H. Grayum et al. 13193 (PMA!); Darién: Parque Nacional del Darién, W slope of Cerro Mali, on ridge between N and S branches of Río Pucuro; ca. 18 km E of Pucuro, 08°04’N 077°16’W, 1000–1200 m, 19 Oct 1987, B.E. Hammel et al. 16426 (MO!, PMA!); South of El Real, region called Alturas de Nique, near Cana mine; along old Camino Real towards Colombia, 07°45’N 077°40’W, 800–1000 m, 22 August 1987, G. McPherson 11541 (MO!); Parque Nacional Darién. Cerro Pirre. Rancho Frio, 08°01’16”N 077°44’04”W, 103 m, 13 abril 2016, O. Ortiz & T. Contreras 2550 (MO!); Distrito de Chepigana. Parque Nacional Darién. Rio Casa Vieja, 676 m, 12 abril 2014, O. Ortiz et al. 2302 (MO!); Along ascent of Serranía de Pirre above Cana Gold Mine between Río Cana and Río Escucha Ruido. (Holdridge Life Zone Map). [Coordinates on original label as 08°30’N, 77°30’W], 07°45’N 077°41’W - 07°45’N 077°43’W, 600–1000 m, 27 July 1976, T.B. Croat 37738 (MO!); Serranía de Pirre, along ascent of Serranía de Pirre above Cana gold mine between Río Cana and Río Escucha Ruido, 07°45’N 077°42’W - 07°45’N 077°43’W, 1000–1310 m, 27 July 1976, Thomas B. Croat 37756 (MO!); Vicinity of gold mine at Cana, 07°45’N 077°41’W, 500–600 m, 26 Jul 1976, T.B. Croat 37674 (MO!); Vicinity Cerro Pirre, along trail from base camp to Rancho Frío on slopes of Cerro Pirre, 07°58’N 077°43’W, 200–450 m, 27 July 1994, T.B. Croat & G. Zhu 77123 (MO, SAR); Panamá: 900 m, 15 Oct 1972, M. Madison 763 (GH); Parque Nacional Altos de Campana. Sendero Zamora, 13 septiembre 2000, R. Aizprúa & L. Martínez B2238 (MO!); Road past Altos de Pacora, 3–3.5 mi NE of Altos de Pacora, 7.8–8.2 mi above Pan Am Highway, 11.1–11.6 mi beyond Lago Cerro Azul, 09°15’N 079°25’W, 700–750 m, 19 Jun 1988, T.B. Croat 68681A (MO!); Cerro Campana, 6.1 miles above Pan-American Hwy, 3.2 miles beyond park entrance and Guarda Bosque Station, 08°41’N 079°56’W, 800 m, 23 March 1993, T.B. Croat 74767 (CM, MO); Capira. Cerro Campana cloud forest, 08°41’N 079°54’W, 600 m, 8 Aug 1970, J. Luteyn & H. Kennedy 1834 (MO!); Middle slopes of Cerro Campana, ca. 1 mile from Interamerican Highway, 08°43’09”N 079°53’25”W, 150 m, 15 June 1976, T.B. Croat 35988 (MO!); Chepo. El Llano-Cartí Road, 8.2 miles N of Inter-American Highway, 09°16’55”N 078°55’55”W, 300–350 m, 27 March 1976, T.B. Croat 33705 (MO!); San Blas: (Comarca de Kunayala): Nusigandí, El Llano-Cartí Road, 1–2 mi N of Nusigandi on road to Cartí, 09°20’N 078°59’W, 250–275 m, 2 Jul 1994, T.B. Croat & G. Zhu 76584 (MO, RSA).
description: Published as part of Croat, Thomas B., Cedeño-Fonseca, Marco & Ortiz, Orlando O., 2024, Revision of Monstera (Araceae: Monsteroideae) of Central America, pp. 1-197 in Phytotaxa 656 (1) on page 158, DOI: 10.11646/phytotaxa.656.1.1, http://zenodo.org/record/13213072