Monstera tenuis K. Koch
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 tenuis

description: 49. Monstera tenuis K.Koch in A. Braun & C. Bouché, Index Seminum Hort. Bot. Berol., Appendix: 4. 1855. (Fig. 85)
Type: —Cultivated at Potsdam, Wildparkstation, 1855, K. Koch s.n. (lectotype K-K000434515! [fragm.], designated by Cedeño-Fonseca et al. 2022). — COSTA RICA. Cartago: Tucurrique, 635 m, Jan. 1899, A. Tonduz 13311 (epitype B-B100144968!], isoepitypes P! three sheets [P00748754, P00748755 & P00748756], US! two sheets [00087942 & 01095187], designated by Cedeño-Fonseca et al. (2022)).
Marcgravia paradoxa [W.Bull, Retail list for 1872: 7. 1872 & Gard. Chron. April 6, 1872: 470. 1872 (‘ Marcgraavia paradoxa ’), nom. inval. (provisional)]; W.Bull ex G.W.Johnson & R.Hogg, J. Hort. Cottage Gard. n.s. 28: 470. 1875 (Johnson & Hogg 1875). TYPE:—Cultivated Knowle, Warwickshire, UK, 12 April 1889, E. Tonks s.n. (neotype K!, three sheets [K000626773, K000626774, K000626775], designated by Cedeño-Fonseca et al. (2022)).
Monstera gigantea Engl., Bot. Jahrb. Syst. 37: 118. 1905, [nom. illeg., non M. gigantea (Roxb.) Schott, Wiener Z. Kunst 1830 (4): 1028. 1830, i.e. Epipremnum giganteum (Roxburgh 1820: 455) Schott (1857: 45)]. TYPE:— COSTA RICA. Cartago: Tucurrique, 635 m, Jan. 1899, A. Tonduz 13311 (holotype B!, isotypes P!, US!).
Robust to massive nomadic vine, appressed-climbing habit. SEEDLINGS: filiform. JUVENILE PLANTS: root climbers; stems light-brown or green, smooth, flattened or cylindrical; internodes 2–10 cm long, 5–10 mm diam.; petiole not visible (covered by blade), dark green, smooth, 2–4 cm long; blades obovate, subcordate at base, acuminate at apex, coriaceous, 5–15 × 4–10 cm, appressed to the phorophyte; fenestrations absent. ADULT PLANTS: root climbers; stems light-brown or green, cylindrical, warty with pustules; internodes 3–8 cm long, 3–14 cm diam., 0.6–1.0 times as long as wide; anchor roots light brown; feeder roots dark-brown; petiole light-green, smooth, 25–70 cm long, sheathed to base of the geniculum; petiole sheath deciduous with fibrous remains; geniculum smooth, flattened adaxially, convex abaxially, 2–5 cm long; blades lanceolate to ovate to lanceolate-oblong, obtuse, truncate, sub-cordate or attenuate at base, obtuse to slightly acuminate at apex, coriaceous, drying yellowish, blackish, brownish or reddish, 45–90 × 35–50 cm, 1.5–2.0 times longer than wide, decurrent on the geniculum, decurrent portion 1–2 mm wide; midrib ribbed adaxially, convex abaxially, drying black to dark brown on both surfaces; primary lateral veins 5–60 per side, slightly sunken adaxially, prominent abaxially, drying blackish or dark brown; collective veins not visible; fenestrations present only in the transition to adult leaves; margins deeply pinnatifid, 5–30 lobes per side, often somewhat drooping, with 3–5 veins per lobe (the middle one the most prominent). INFLORESCENCES on ascending stems, 1–5 simultaneously at flowering time, arranged in the leaf axils; peduncle smooth, 4–10 cm long, 3–4(6) cm diam.; spathe obtuse to short-acuminate, green-yellowish externally and white-cream externally during development, completely open or tearing in fragments, deciduous after anthesis, 15–40 × 10–20 cm, as long as the spadix; spadix white-cream during development, yellow at anthesis, 13–40 cm long, 2–6 cm diam.; basal sterile flowers 5–8 mm long, with a yellowish stigmatic secretion; fertile flowers 0.9–1.5 cm long; stamens 2–10 mm long, with laminar filaments; anthers 1.5–2.0 mm long; ovary rectangular in longitudinal section, ribbed, 7–11 × 2–3 mm; style hexagonal, 4–6 × 2–3 mm; stigmatophore semi-columnar; stigma linear, with a yellow stigmatic secretion; berries with a pale-green stylar cap during development, mature stylar cap moss-green; pulp gray; seeds black with light brown dots, elongated, 6–10 mm long.
Distribution and ecology: — Monstera tenuis ranges from Nicaragua to Costa Rica and Panama, at 0–1766 m. It occurs in Tropical moist forest, Tropical wet forest, Premontane wet forest and Premontane rain forest life zones; in primary and secondary forest, and open areas.
Phenology: —Flowering has been recorded in February, May, November–December, and fruit in January–March, and May–September.
Discussion: —The species, a member of sect. Marcgraviopsis, is characterized by the light green petiole, sheathing to base of the geniculum, with deciduous wings leaving fibrous residues, leaf blades deeply pinnatífid and never fenestrate, inflorescences with the spathe white-cream externally, spadices up to 40 cm long with short peduncles (<10 cm), and the infructescence moss green at maturity. It could be confused with M. pinnatipartita, but that species has the petioles speckled, with wings of the leaf sheath persistent and involute, and it lacks the shingling juvenile phase.
Monstera tenuis is among the most robust species of the genus, only rivalled in the size of the leaves by M. deliciosa and M. alfaroi, and the recently described Panamanian M. gigas, the latter with leaves which can reach 3 m long (Cedeño-Fonseca et al. 2021b, 2022). Monstera tenuis also has the largest spadix of any species, though overall inflorescence size is eclipsed by M. titanum also from Panama, whose combined peduncle and spathe length can approach 1 m (Cedeño-Fonseca et al. 2021b, 2022).
For more details about the taxonomic comments and nomenclatural note see Cedeño-Fonseca et al. (2022).
Additional specimens examined: — NICARAGUA. Atlántico Sur: Municipio de Nueva Guinea, Reserva Indio-Maiz, colinas de piedra fina, 11°25’N 084°13’W, 200–300 m, 6 enero 1999, R.M. Rueda et al. 9897 (MO!); Caño Costa Riquita, ca. 1.8 km SW of Colonia Naciones Unidas, above (S of) road between Colonia Nuevo Léon and Colonia Naciones Unidas, 11°43’N 084°18’W, 150–180 m, 06 November 1977 – 07 November 1977, W.D. Stevens 5046 (MO!); Río San Juan: Near Caño Chontaleño, 20 km NE of El Castillo, 11°08’N 084°12’W, 200 m, 18 April 1978 – 21 April 1978, D.A. Neill & P.C. Vincelli 3619 (MO!); Los Filos, near Loma Los Filos, Río Santa Cruz; recently logged lowland moist forest on clay soils, 11°08’N 084°19’W, 100–200 m, 6 Sep. 1993, J. Salick 8113 (MO!). COSTA RICA.
Alajuela: San Ramón, Peñas Blancas, R.B. Monteverde, Río Peñas blancas, Laguna, 850 m, 27 May 1988, (Fr.), E. Bello 413 (CR!); Primary forest and perimeter, Finca Los Ensayos ca 11 miles NE of Zarcero, 850 m, 15 August 1977, (Infer.), T.B. Croat 43594 (CR!, MO!); Along road between Cañas and Upala, 400 m, 24 June 1976, (Infer.), T.B. Croat 36322 (MO!); San Isidro de San Ramón, 1259 m, 21 Octubre 1986, (Fr.), G. Herrera 57 (MO!); 3 miles north of San Miguel, 380 m, 26 Mayo 1976, (Infer.), T.B. Croat 35644 (MO!); Cartago: Paraíso, Cachí, Remnant trees near Río Naranjo, 3 km E of Cachí, 1300 m, 20 April 1969, (Fr.), R. Lent 1589 (CR!); Turrialba. Peralta. (Tres Equis), 450 m, 15 April 1935, (Fr.), F. Solís 237 (CR!); Turrialba, La Suiza, Jardín Botánico Carlos Lankester, 6 km al este de la ciudad de Cartago, 1370 m, 22 October 1994, (Infer.), A. Quesada 21 (CR!); Turrialba, Santa Cruz, Sobre ríos Guayabo, Lajitas y monumento, Crece a orillas de las quebradas, 1100 m, 27 June 1992, (Fr.), G. Rivera et al. 1888 (CR!); Turrialba, Turrialba, CATIE, Confluencia del Rìo Tuis y el Rìo Reventazòn, 580 m, 15 June 1994, (Fr.), G. Herrera 7157 (CR!); Turrialba, Along road between Juan Viñas and Turrialba, 1 July 1976, (Fr.), T.B. Croat 36838 (MO!); Cartago, Wooded slope along the Río Sombrero just outside of El Muñeco, 1300 m, 25 June 1972, (Fr.), J. Luteyn 3240 (MO!); Cartago, Dulce Nombre, Jardín Botánico Lankester, 1360 m, 26 September 2015, (Fr.), M. Cedeño & M. Blanco 835 (USJ!); Guanacaste: Liberia, Mayorga, P.N. Guanacaste, Estación Mengo, Sendero al potrero, lado sur, 1100 m, 15 July 1989, (Fr.), INBio 185 (CR!, MO!); Bagaces, Mogote, P.N. Rincón de la Vieja, Sendero a San Jorge, límite este, Cabecera de Quebrada Tapezco, 770 m, 12 June 1991, (Fr.), G. Rivera 1365 (CR!); Bagaces, La Fortuna, Z. P. Miravalles, Cuenca del Tempisque, Zona Protectora Volcan Miravalles, 900 m, 24 May 1997, (Fr.), F. Alvarado et al. 187 (CR!); Liberia, Mayorga, Sector Cacao hacia la Estación 2.5 Km después del río Góngora, en bosque remanente, 900 m, 1 May 2000, (Fl.), L. Acosta 1100 (CR!); Liberia, Mayorga, Estacion Cacao, Sendero Pedregal, Bosque primario, 1100 m, 10 February 1995, (Fl.), B. Gamboa 63 (CR!, MO!); Parque Nacional Rincón de la Vieja, 900–1200 m, 27 January 1983, (Fl.), G. Davidse 23387 (MO!); Heredia: Sarapiquí, Near Puerto Viejo along road near the Río Sucio, 20 m, 27 May 1976, (Infer.), T.B. Croat 35712 (MO!); Sarapiquí, La Selva Field Station, 100 m, 3 January 1978, (Infer.), T.B. Croat 44229 (MO!); La Selva Biological Station, 100 m, 16 June 1984, (Fr.), B. Jacobs 2370 (MO!); Along road between San Jose and Puerto Viejo, 100 m, 1 October 1987, (Infer.), T.B. Croat 68380 (MO!); La Selva Biological Station, 100 m, 9 July 1984, (Fr.), B. Jacobs 2770 (MO!); Limón: Pacuarito, Banana and cacao plantations on level areas between Siquirres and the Río Pacuare, and remnant forest on steep hills south of the railroad bridge over the río Pacuare, 80 m, 20 December 1969, (Fl.), W. Burger & R. Liesner 6955 (CR!, MO!); Along highway 32 near Río Madre, ca. 1 miles southwest of Limón, 10 m, 13 August 1977, (Fr.), T.B. Croat 43306 (CR!, MO!); Pococí, Colorado, P.N. Tortuguero, Estación Agua Fría, 4 km al Norte siguiendo el cauce del Río Agua Fría hasta la unión con el Río Tortuguero, Bosque perturbado, 40 m, 15 March 1988, (Infer.), R. Robles 1733 (CR!, MO!); Pococí, Guapiles, Bosque Lluvioso, alrededores de la casa, bordes de bosque, 350 m, 18 August 2005, (Infer.), L. Acosta 3566 (CR!); Talamanca, 7 km SW of Bribrí, 100–250 m, 4 May 1983, (Fl.), L. Gómez 20317 (CR!, MO!); 20 mi SE of Limón on road to Punta Cahuita, 0 m, 11 August 1977, (Infer.), T.B. Croat 43171 (MO!); Siquirres, 2 miles NW of Río Siquirres on Highway 32 from Limón to Turrialba, 200 m, 11 August 1977, (Infer.), T.B. Croat 43160 (MO!); Along road from Río Frio to Limón, 360 m, 2 October 1987, (Infer.), T.B. Croat 68425 (MO!); 20 mi SE of Limón on road to Punta Cahuita, 0 m, 11 August 1977, (Infer.), T.B. Croat 43173 (MO!); Puntarenas: Buenos Aires, Biolley, P.I. La Amistad, Cordillera de Talamanca, area around Río Canasta, 9.5 airline km NW of Agua Caliente, between Cerro Frantzius and Cerro Pittier, 1550 m, 6 September 1984, (Fr.), G. Davidse et al. 28393 (CR!, MO!); Buenos Aires, Biolley, P.I. La Amistad, Estación Altamira, cerro Biollley, Cuenca Térraba-Sierpe, 1766 m, 1 June 1996, (Fr.), J. Quesada 1623 (CR!, MO!); Coto Brus, Pittier, Pittier, Santa María, Sobre sendero al Río Canasta, 1700 m, 30 July 2000, (Fr.), L. Acosta 2352 (CR!); Coto Brus, Pittier, Estacion Pittier, Sendero Altamira, 1650 m, 28 January 1995, (Fr.), M. Chinchilla 7 (CR!); Buenos Aires, Potrero Grande, Buenos Aires, Potrero Grande, La Lucha, Punto 8, Bosque denso 5–25 m DAP 30–90 cm; Predominio de Hampea appendiculata, Cecropia sp, Ruagea glabra, Lauraceae y helechos arborescentes, 1400 m, 20 February 2008, (Fr.), D. Santamaría 7027 (CR!); Vicinity of San Vito de Java, Disturbed primary forest, 4000 f, 28 February 1976, (Fr.), T.B. Croat 32902 (MO!); Corredores, En el camino que va desde La Estación Biolgógica Las Cruces hasta el Río Jaba, 1170 m, 16 June 2003, (Infer.), R. Moran 6481 (MO!); Coto Brus. Finca Las Cruces, 5000 f, 17 March 1969, (Fr.), W. Stevens 233 (MO!); Coto Brus, San Vito, Estación Biológica Las Cruces, 1200 m, 2 May 2015, (Infer.), M. Cedeño 781 (USJ!); Comunidad de Monteverde, En arbol en potrero abierto, 1450 m, 26 June 1977, (Fl.), V. Dryer 1535 (CR!); San José: Turrubares, Carara, P.N. Carara, Cuenca del Río Grande de Tárcoles, Ridges W of Río del Sur (E foothills of Montañas Jamaica), bet. Carara and El Sur, 280 m, 3 April 1993, (Infer.), M.H. Grayum 10446 (CR!, MO!); Perez Zeledon, About 1 mile beyond divide between San Isidro del General and coastal town of Dominical, 900 m, 22 May 1976, (Infr.), T.B. Croat 35320 (MO!). PANAMA. Bocas del Toro: Caribbean slopes of Cerro Fábrega at foot of ‘Falso Fábrega’ in Palo Seco Reserve, second northernmost tributary (on map) of Culubre river: Pavón Camp, 09°09’54”N 082°40’45”W, 980 m, 20 March 2005, A. Monro & S. Cafferty 4800 (BM, PMA); Changuinola, Dos Bocas, Unión del Changuinola con el Teribe, 09°22’18”N 082°31’54”W, 21 Feb 1980, M.D. Correa et al. 3536 (MO!, PMA!); Changuinola, Dos Bocas, Unión del Changuinola con el Teribe, 09°22’18”N 082°31’54”W, 21 Feb 1980, M.D. Correa et al. 3536 (MO!); Approximately 3 km S of Tiger Key. UTM 1,015,00m N; 363,000m E. Moist tropical forest with Hura crepitans and Theobroma cacao, 09°11’24”N 082°14’24”W - 09°11’25”N 082°14’54”W, 0–30 m, 25 Feb 1989, P.M. Peterson & C.R. Annable 7127 (US!); Approximately 3 km S of Tiger Key. UTM 1,015,00m N; 363,000m E. Moist tropical forest with Hura crepitans and Theobroma cacao, 09°11’24”N 082°14’24”W - 09°11’25”N 082°14’54”W, 0–30 m, 25 Feb 1989, P.M. Peterson & C.R. Annable 7127 (MO!); Along road between Almirante and Ojo de Agua 3–6 km W of Almirante. Disturbed vegetation along road, 09°18’24”N 082°26’48”W, 30–300 m, 4 Aug 1976, T.B. Croat 38209 (MO!); Station Milla 7.5 on Changuinola-Almirante Railroad, along a slender ridge to World War II communications facility, ca. 2 km NW of ruins of U.S. Army Military barracks, 09°21’54”N 082°27’12”W, 0–100 m, 03 August 1976, T.B. Croat 38090 (MO!); Chiriquí: Near Cerro Colorado, c. 3.5 miles along road from Chami [Chame] Camp. [Coordinates on original label: 8º35’N, 81º45W], 08°28’57”N 081°45’56”W, 1350 m, 17 April 1986, G. McPherson 9004 (MO!); ”Ojo de Agua”, property of Ratidon Hartmann, vicinity of Santa Clara (between Volcán and Río Sereno), 08°51’N 082°45’W, 1520 m, 17 June 1987, T.B. Croat 66292 (B, K, MO, NY, US); Along road in vicinity of branch in road to Cerro Colorado and Escopeta, above Río San Félix near town of San Felix (ca. 13 miles N of Río San Félix bridge), 08°27’N 081°47’W, 800–1200 m, 15 March 1976, T.B. Croat 33460 (MO!); Cerro Colorado, along road above San Félix, 29 km above bridge over Río San Félix (7.9 km above turnoff to Escopeta), 08°32’07”N 081°49’11”W, 1500 m, 14 July 1976, T.B. Croat 37097 (MO!); Along road from Volcán to Río Serano, ca. 12 km from Escuela San Benito in Volcán, 08°49’48”N 082°42’30”W, 1200 m, 8 Aug 1974, T.B. Croat 26495 (MO!); Cerro Colorado, above San Félix along mining road 18–27 miles off of Pan-American Highway (above Chame or turn-off to Escopeta), 08°32’N 081°49’W, 1200–1500 m, 12 March 1976, T.B. Croat 33073 (MO!); Fortuna-Chiriqui Grande, 1.8 mi. NW of center of dam, 08°45’N 082°18’W, 1080 m, 27 Jun 1994, T.B. Croat & G. Zhu 76499A (MO!); Coclé: La Pintada. Alto Calvario above El Copé, ca. 6 km N of El Copé; Atlantic slope, along trail which leads W off old lumber trail which leads down to Las Ricas, Limón and San Juan, 08°40’41”N 080°35’47”W - 08°41’04”N 080°35’50”W, 710–800 m, 22 June 1988, T.B. Croat 68749 (MO!); Darién: Cerro Sapo; ca. 5 km south of Garachiné; along ridge at north approach to cerro, 07°59’N 078°25’W, 600–800 m, 23 March 1986, B.E. Hammel et al. 14858 (MO!); Panamá: Chepo. El Llano-Cartí road, 8.4 mi beyond the highway, 09°16’55”N 078°55’55”W, 500 m, 5 Dec 1979, T.B. Croat 49133 (MO!).
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 pages 172-173, DOI: 10.11646/phytotaxa.656.1.1, http://zenodo.org/record/13213072