Monstera obliqua Miq., Linnaea

Croat, Thomas B., Cedeño-Fonseca, Marco & Ortiz, Orlando O., 2024, Revision of Monstera (Araceae: Monsteroideae) of Central America, Phytotaxa 656 (1), pp. 1-197 : 127-130

38. Monstera obliqua Miq., Linnaea 18: 79. 1844. ( Figs. 62 , 63 )

Type: — SURINAME. [Wanica]: Vredenburger-Zandrits , October 1842, H.C. Focke 719 (holotype U n.v., photos: BH, SEL! sheet 006766) .

Monstera falcifolia Engler, Bot. Jahrb. 37: 117. 1905. TYPE:— BRASIL. Amazonas , Jurua Miry, July 1901, Ule 5622 (holotype B, photos: BH, GH, US, isotypes K, L!, MG, photo: BH).

Monstera fendleri Engler, Bot. Jahrb. 37: 117. 1905. TYPE:— TRINIDAD. 1877-1880, Fendler 736 (holotype K!, isotypes NY, P!).

Monstera sagotiana Engler, Bot. Jahrb. 37: 117. 1905. TYPE:— GUYANA FRANCESA, Karouany , Sagot 609 (holotype BM!, photo: BH).

Monstera snethlagei Krause, Notizbl. Bot. Gart. Berlin-Dahlem 9: 272. 1925. TYPE:— BRASIL, Maranhão, Jury-assu, Mta. de Allegria, Ketterpflanze im Igapowald , gelb, Hüllblatt ebenfalls gelb, 14 November 1923, Snethlage 327 (holotype B, photos: BH, F!, GH, US) .

Nomadic vine, appressed-climbing habit. SEEDLINGS: bearing foliage leaves. JUVENILE PLANTS: root climbers; stems smooth, dark green; internodes 3–5 cm long, 2–5 mm diam.; petiole conspicuous, dark green, smooth, 5–11 cm long, sheathing to base of the geniculum; petiole sheath deciduous; blades lanceolate, truncate at base, acuminate at apex, subcoriaceous, 7–13 × 2–4 cm, not appressed to the phorophyte; fenestrations absent. ADULT PLANTS: root climbers; stems smooth, light to dark green; internodes 2–10 cm long, 0.3–0.8 mm diam., 10.0–12.5 times longer than wide; cataphylls light-green, deciduous but leaving dry fragments on peduncles; anchor roots black; feeder roots black; petiole light green, smooth, 5–18 cm long, sheathing to the geniculum, petiole sheath deciduous; geniculum smooth, 3–5 mm long; blades lanceolate to narrowly elliptical, cuneate at base, acuminate at apex, membranous to subcoriaceous, drying blackish, reddish, light brown or grayish, 12–23 × 3–10 cm, not decurrent on geniculum; midrib ribbed adaxially, convex abaxially; primary lateral veins 4–8 per side, obscure adaxially, prominent abaxially, departing midrib at 35°–50°; secondary veins inconspicuous; collective veins not visible; fenestrations absent or scarcely developed (in Central America); margins entire. INFLORESCENCES on ascending stems, 1–3 simultaneously at flowering time, arranged in the axils of the leaves or cataphylls; peduncle smooth, 10–17 cm long, 5–6 mm diam.; spathe acuminate, light-green during development, yellow externally and white internally at anthesis, the margins towards the apex involute, deciduous at the end of anthesis, up to 4 cm longer than the spadix; spadix with green style margins and white at the medial part during development, cream at anthesis, 3–5 × 0.5–1.0 cm; basal sterile flowers scarce or absent; fertile flowers 4–7 mm long; stamens 1–2 mm long, with laminar filaments; anthers 1–2 mm long; ovary square in longitudinal section, ribbed, 1.5–2.0 × 1.5–2.0 mm; style square or hexagonal, 1.5–2.0 × 2.5–3.0 mm; stigma linear; berries with a moss-green stylar cap during development, mature stylar cap orange; pulp white; seeds black, 3–5 mm long.

Distribution and ecology: — Monstera obliqua ranges from Costa Rica to the Pacific slope and adjacent lowlands of the departments of Chocó and Valle in Colombia, and to Venezuela, the Guianas, and throughout the Amazon basin, at 0–1410 m, in Tropical moist forest, Tropical lower montane wet forest and Montane moist forest life zones.

Phenology: —Flowering has been recorded from July to November. Fruiting in January, March July and November.

Discussion: —The species is a member of sect. Monstera . It differs from the other species of the genus in Costa Rica by its slender petioles (<0.5 cm diam.), sheathed to the base of the geniculum, the entire, narrowly lanceolate, not or hardly fenestrate leaf blade; the infructescence with the stylar layer orange with white pulp beneath. Vegetatively, individuals of Monstera obliqua with fenestrate leaves can be confused with the dry forest morphotype of M. adansonii . Another species with which it could be confused is M. gambensis , which has the petiole rough, persistent petiolar sheaths with involute wings, and is known only from a collection on the Pacific side in the area of La Gamba, Golfito.

In its current conception, Monstera obliqua is a very variable and widespread species, including forms with widely varying and sometimes extreme leaf fenestration patterns, occurring across much of lowland wet tropical South America. It may be that further study will show that it covers several species. There are a number of synonyms based on South American and West Indian representatives which it is beyond the scope of this paper to evaluate ( Cedeño-Fonseca et al. 2022).

Additional specimens examined: — COSTA RICA. COSTA RICA. Limón: Talamanca, Sixaola, San Miguel de Sixaola , Finca -albergue de ASACODE, 35 m, 28 July 1994, (Fr.), J. Sánchez et al. 340 ( CR!) ; Talamanca, Bratsi, Suretka , Bosques cercanos al sitio de exploración petrolera, 200 m, 19 July 1995, (Fl., Fr.), A. Cascante et al. 551 ( CR!) ; Limón, Talamanca, Cahuita, Between Bri Bri and Sixaola , NW of Paraíso, Disturbed forest, 50 m, 5 July 1983, (Fr.), K. Barringer et al. 3489 ( CR!, MO!) ; Talamanca, Sixaola, Hills between headwaters of Quebrada Mata de Limón and upper branches of Quebrada Tigre, and lowland forest of Quebrada Tigre drainage, Finca Anai, (Sixaola region), 28 m, 18 November 1984, (Fl., Fr.), M.H. Grayum et al. 4458 ( CR!, MO!) ; Talamanca, Sixaola, Headwaters of quebrada Mata de Limón , westernmost fork, Finca Anai , (Sixaola region), 23 m, 17 November 1984, (Fr.), M.H. Grayum et al. 4439 ( CR!, MO!) ; Talamanca , Cahuita, Gandoca, El Llano entre Fila Manzanillo y Río Creek . Atrás de la playa, 80 m, 27 March 1995, (Fr.), G. Herrera & E. Sandoval 7600 ( CR!) ; Limón, Valle La Estrella, Fila Espavel , 200 m, 3 July 2000, (Fr.), L. Acosta 2117 ( CR!) ; Talamanca, Sixaola, Sendero Cerillo , 1 m, 3 March 1999, (Fr.), U. Chavarría 1920 ( CR!) ; Talamanca, Sixaola, San Miguel , senderos en la ruta a Manzanillo, 30 m, 16 January 1997, (Fr.), J. González 1582 ( CR!) ; Lugar, Camino entre Fila Dimat y Río Uren , 22 October 1985, (Fr.), L. Gómez 23765 ( MO!) ; Ca. 10 miles S of Punta Cahuita , 70 m, 11 August 1977, (Infer.), T. Croat 43199A ( MO!) ; Talamanca, Bribri, Proyecto ARA, 4 m, 30 September 2018, (Fl., Fr.), M. Cedeño et al. 1481 ( USJ!) ; Talamanca, Bribri, Proyecto ARA, 4 m, 30 September 2018, (Fr.), M. Cedeño et al. 1482 ( USJ!) . PANAMA. Bocas del Toro: Above Chiriquí Grande on side road 10 mi from continental divide ; on trail off pipeline trace, 8°55’N, 82°10’W, 300 m, 28 May 1988, G. McPherson 12569 ( MO!) ; Hill just south of Chiriquí Grande; at end of pipeline access road 2 mi N of 2nd large bridge N (10 mi.) of cont. divide, 8°54’N, 82°10’W, 350–500 m, 10 Mar 1986, B.E. Hammel et al. 14743 ( MO!) ; Vicinity of Chiriquí Lagoon , 8 Oct 1940, H. Wedel 1091 ( MO!) ; Milla , 7.5, 26 July 1971, T.B. Croat & D. Porter 16277 ( MO!) ; Chiriquí: Chiriquí Grande-Fortuna , along Continental Divide from road branching N off main Fortuna-Chiriquí Grande Highway near Continental Divide, 1.1 mi from main highway, 8°44’N, 82°17’W, 1200 m, 11 Mar 1985, T.B. Croat & M.H. Grayum 60347 ( MO!) ; Coclé: Cerro Pilon near El Valle , 700–900 m, 700–900 m, 10 June 1967, J. Duke 12155 ( MO!) . Between Cerro Pilon and El Valle , 700–900 m, 15 Aug 1967, J. Duke 13993 ( MO!) ; El Valle , 1000 m, 24 Dec 1972, A. Gentry 6893 ( MO!) ; El Valle ; end of road leading to Turstico Hotel, 11 May 1977, J. Folsom 3111 ( MO!) ; Trail between the Río Blanco and the Continental Divide N of El Cope and El Potroso sawmill, 400–1700 ft, 14 Dec 1980, J. Sytsma et al. 2580 ( MO!) ; Vicinity of El Valle , 600–1000 m, 8 Dec 1938, P. Allen 1227 ( MO!) . Mountains beyond La Pintada , 400–600 m, 16 Feb 1935, Hunter & P. Allen 544 ( MO!) ; Cerro Pilón , 2000–2700 ft, 28 Mar 1969, J. Dwyer et al. 4565 ( MO!) ; Continental divide N of Penonome on road to Coclesito, 1600 ft, 25–26 July 1978, B.E. Hammel 4039 ( MO!) ; Foot of Cerro Pilón , above El Valle de Antón. Rain forest, 2000 ft, 28 Mar 1969, D. Porter et al. 4612 ( MO!) ; El Valle de Anton , La Mesa , 1000 m, 1 Apr 1973, Helen et al. 3011 ( MO!) ; El Valle site , on the end of the trail from the end of the road to the site, 24 Apr 1968, Kirkbride 1082 ( MO!) ; Continental divide , 4 mi past Llano Grande on road to Cascajal, NW of Penónome, 500 m, 9 Apr 1981, J. Sytsma 3878 ( MO!) ; Road from Penonomé to Coclecito , 9 km N of Llano Grande, tributary on Río Caseaja, 11 Oct 1978, W. D’Arcy & B.E. Hammel 12282 ( MO!) ; Colón: Santa Rita Ridge, Santa Rita (Arriba)-Cerro Azul, 09°20’21’’N, 79°46’47’’W, 200–260 m, 23 July 1990, M.H. Grayum & R. Evans 9922 ( MO!) ; Santa Rita Ridge Road , 6.5 mi E of Boyd-Roosevelt Hwy, 09°21’15”N, 79°44’00”W, 370 m, 16 July 1994, T.B. Croat & G. Zhu 76941 ( GB, MO, SAR) ; 25–26 kms from Transisthmica Hwy on Santa Rita Ridge , 09°26’N, 079°37’W, 500 m, 21 Oct 1981, S. Knapp et al. 1733 ( MO!) ; Santa Rita Ridge , E of Agua Clara rain gauge, 4 March 1973, H. Kennedy 2753 ( MO!) ; Santa Rita Ridge, In forest on Tassell’s property, 8 Nov 1974, S. Mori & Kallunki 3026 ( MO!) ; Santa Rita lumber road , 8.7 km E of Transisthimian Highway, 15 June 1977, J. Folsom 3690 ( MO!) ; Santa Rita Ridge Road , 7.8 km from the Boyd-Roosevelt Hwy, ca 25 km W of Colón, 23 Aug 1975, S. Mori & R. Dressler 7907 ( MO!) ; Trail S of Río Guanche , on ridge to Cerro Pan de Azúcar, 200 m, 20 Sept 1974, S. Mori & Kallunki 2031 ( MO!) ; 9 km W of Llano Grande just S of Cascajal , 800 ft, 11 Oct 1978, B.E. Hammel & W. D’Arcy 5099 ( MO!) ; Darién: Vicinity Cerro Pirre, along trail from base camp to Rancho Frio on slopes of Cerro Pirre, 07°58’N, 77°43’W, 200–450 m, 27 July 1994, T.B. Croat & G. Zhu 77130 ( MO!) ; Parque Nacional Darién , subiendo por la trocha limitrofe desde Casa Vieja hacia Cerro Sapo, 07°58’N, 78°23’W, 500–800 m, 25 May 1991, G. Herrera et al. 1000 ( MO!) ; Parque Nacional Darién , Serranía de Cerro Sapo , por la trocha limitrofe del PND entre Casa Vieja y Cerro Sapo, 07°58’N, 78°23’W, 20–400 m, 24 Nov 1990, G. Herrera & J. Polanco 742 ( MO!) ; Parque Nacional del Darién . Slopes of Cerro Mali; head waters of S branch of Río Pucuro; ca. 22 km E of Pucuro, 08°04’30”N, 77°14’00”W, 1300–1400 m, 21 Oct 1987, H. Cuadros et al. 3912 ( MO!) ; Parque Nacional del Darién . Ridge between Río Topalisa & Río Pucuro ca. 13 km E of Pucuro; Quebrada Pobre to Mi Casita, 8°03’N, 77°20’W, 450–600 m, 14 Oct 1987, G. Nevers et al. 8316 ( MO!) ; Parque Nacional del Darién Ridge between N & S Branches of Río Pucuro; in forest N of old village of Tacarcuna; ca. 18 km E of Pucuro, 8°05’N, 77°16’W, 600–800 m, 24 Oct 1987, B.E. Hammel et al. 16486 ( MO!) ; Cerro Tacarcuna Expedition . South slope of Cerro Tacarcuna above Río Pucuro base camp, 700–1000 m, 25 January 1975, A. Gentry & S. Mori 13899 ( MO!, PMA!) ; Cerro Tacarcuna Expedition . Trail from Pico Mali to old Tacarcuna village on Río Tacarcuna, premontane wet forest, 700 m, 7 Feb 1975, A. Gentry & S. Mori 14181 ( MO!) ; Cativo Swamp, Río Chucunaque , ca. 1/2 hr below Morti, 18–31 May 1967, J. Duke 11749 ( MO!) . 10 km NE of Jaqué, headwaters of Río Pavarandó , 1400 ft, 30 Jan 1981, J. Sytsma & W. D’Arcy 3352 ( MO!) ; 10 km NE of Jaqué, ridge between Río Tabuelita and Río Pavarandó , 1400–1600 ft, 1 Feb 1981, W. D’Arcy &. J. Sytsma 14551 ( MO!) ; Near Jacque at Enseñada del Guayabo , Apr 1980, N. Garwood 1024 ( MO!) ; Cerro Mali : Cerro Tacarcuna Expedition, Trail from Tacarcuna village on Río Tacarcuna to Cerro Mali , 800–1300 m, 16 Jan 1975, J. Gentry & S. Mori 13601 ( MO!) ; Parque Nacional Darién : S of Garachine near Pacific coast above Casa Vieja along boundary trail, W flank of Serranía Sapo, 7°58’N, 78°23’W, 150–300 m, 22 May 1991, Hensold 1083 ( MO!, PMA!) ; Punta Guayabo Grande : N of Punta Guayabo Grande, trail to ridge top, 200–600 ft, 21 Apr 1980, T. Antonio & J. Hahn 4346 ( MO!, PMA!) ; Panamá: Along trail to Cerro Brewster from Río Pacora Valley , 9°20’N, 79°15’W. Forested slopes c. 650 m, 9°20’N, 79°15’W, 650 m, 21 Nov 1985, G. McPherson 7558 ( MO!) ; 1 mi N Cerro Azul , 2300 ft, 27 May 1966, E. Tyson & K. Blum 4088 ( FSU, MO) ; El Llano-Carti Road , 10 km from Interamerican Hwy, 5 Oct 1974, S. Mori & Kallunki 2326 ( MO!) ; Campo Tres , 3 mi NE of Altos de Pacora, 500–800 m, 10 Mar 1973, R. Liesner 578 ( MO!) ; Cerro Azul , 23 June 1972, T.B. Croat 17304 ( MO!) ; El Llano-Cartí Road , 09°16’N, 078°58’W, 1000 ft, 6 Sep 1980, J. Sytsma 996 ( MO!) ; El Llano-Carti road , 12 km N of Pan. Am. Hwy at El Llano , 400 m, 11 Mar 1974, M. Nee 10450 ( MO!) ; Cerro Azul , 24 Mar 1969, D. Porter et al. 4070 ( MO!) ; D. Porter et al. 4098 (MO!); 2–3 mi S of Goofy Lake, road to Cerro Jefe , 2000–2200 ft, 10 Dec 1966, H. Lewis et al. 264 ( MO!) ; Near foot of Loma Larga , east of Cerro Azul (Goofy Lake), 5 Apr 1973, R. Dressler 4319 ( MO!, PMA!) ; vicinity of Finca Neptuno, 3.5 km NE of Lago Cerro Azul on road to Cerro Jefe, 600–800 m, 11 May 1974, M. Nee 11524 ( MO!) . El Llano-Carti Road , 9.6 km from Inter-American Highway, 350 m, 26 May 1975, S. Mori & Kallunki 6402 ( MO!) ; Comarca Guna Yala : Nusagandí , 30 May 1993, Marrianne 25 ( MO!) ; Trail from mouth of Río Irgandí to a tributary of Río Cartí Senni . Two hours through second growth, one hour through forest, 9°25’N, 78°51’W, 9°25’N, 78°51’W, 20 Dec. 1985, G. Nevers & G. Herrera 6580 ( MO!) ; Cangandi , 9°24’N, 79°24’W. 9°24’N, 79°24’W, 30 m, 10 Feb 1986, G. Nevers & G. Herrera 7041 ( MO!) ; Cangandi, hills around village, Assoc: Cespedizia macrophylla, 9°24’N, 79°24’W, 9°24’N, 79°24’W, 50 m, 13 Dec. 1985, G. Nevers et al. 6487 ( MO!, PMA!) ; El Llano-Cartí Road, 19.1 km from Interamerican Hwy ; elev. 350 m. 9°19’N, 78°55’W, 9°19’N, 78°55’W, 350 m, 4 Mar 1985, G. Nevers et al. 4951 ( MO!) ; Campamanto Nusgandi, en ELC a 19.1 km de la vía Panamaericana, Sendero Wedar Igar, 9°11’N, 78°15’W, 200–350 m, 31 Oct 1992, G. Herrera et al. 1265 ( MO!, PMA!) ; Nusagandí; El Llano-Cartí Road, 9 mi N of main highway; Nergan Igar (Nergan Trail), 09°20’N, 79°00’W, 350 m, 2 July 1994, T.B. Croat & G. Zhu 76563 ( CM, MO) ; Trail east of Cangandi-Mandinga airport road, 2–5 mi S of Mandinga airport. 27 Oct 1967, J. Duke 14813 ( MO!) ; Cerro Habú , trail from Río Sidro, primary wet forest, 09°23’N, 078°49’W, 800–1400 ft, 18 Dec 1980, J. Sytsma et al. 2635 ( MO!) ; On trail to inland village of Armila , 3 to 8 km SW of Puerto Obaldía, 21 June 1975, S. Mori et al. 6798 ( MO!) ; Puerto Obaldía and trail to Colombian Frontier , 0–500 m, 28 Apr 1980, W. D’Arcy 13624 ( MO!) ; 3–4 hours up Río Mulatupu , 17 Aug 1967, Kirkbride 229 ( MO!) ; El Llano-Cartí road, 10.5 mi from Interamerican Hwy, 09°18’N, 079°58’W, 550 m, 14 Mar 1985, T.B. Croat 60487 ( MO!) ; Nusagandi: Sendero Wedar , 9°18’N, 78°58’W, 300–400 m, 19 July 1986, McDonagh et al. 174 ( BM) ; Veraguas: Slopes of Cerro Tute , along trail from between first and second creeks N of height above Alto de Piedra; forest, 08°30’N, 81°07’W, 600–750 m, 21 March 1987, G. McPherson 10730 ( MO!) ; Trail on ridge to summit of Cerro Tuté , Cordillera de Tute . 1 km past Escuela Agricola Altos de Piedra, just W of Santa Fe, upper montane and elfin forest, 08°36’N, 081°06’W, 1250–1410 m, 15 December 1981, S. Knapp & J. Sytsma 2532 ( MO!) ; Vicinity of Escuela Agricola Alto Piedra near Santa Fe , 0.3 mi beyond the fork in the road near the agricultural school toward Atlantic coast, along trail to top of Cerro Tute, 1050–1150 m, 29 November 1979, T.B. Croat 48887 ( MO!, PMA!) ; Carribbean slope above Río Primero Brazo 5 mi NW of Santa Fe , 700–1200 m, 18–19 Mar 1973, R. Liesner 801 ( MO!) ; Along trail to summit of Cerro Tute , ca. 3 km above Escuela Agricultura Alto Piedra near Santa Fé, 2600–2800 ft, 4 Jan 1981, J. Sytsma & T. Antonio 2987 ( MO!) ; Vicinity of Escuela Agricultura Alto Piedra , near Santa Fé along trail to top of Cerro Tute, 2800 ft, 3 Apr 1980, T. Antonio 3978 ( MO!) ; Along road from Santa Fé to Río Calovebora 0.6 mile beyond Escuela Agricola Alto Piedra , 735 m, 4 Apr 1976, T.B. Croat & J. Folsom 34133 ( MO!) ; 0.6 mi beyond Escuela Agricola Alto Piedra , 730 m, 4 Apr 1976, T.B. Croat & J. Folsom 34000 ( MO!) ; Caribbean slope above Río Primero Brazo 5 mi NW of Santa Fé , 700–1200 m, 18–19 Mar 1973, T.B. Croat 23146 ( MO!) ; Road beyond Escuela Agricola Alto Piedra , above Santa Fé, Atlantic watershed, 800–1000 m, 1 Jan 1975, J. Luteyn & R. Wilbur 4566 ( DUKE!) ; 1 km past Agricultural School , forested slope to the rear. Road from Santa Fe, 1000–1200 m, 5 Feb 1977, J. Folsom & L. Collins 1610 ( MO!) .

Figures

FIGURE 62. Monstera obliqua from Manzanillo, Costa Rica. (A) Sterile flower; in lateral view (left), and in longitudinal section (right). (B) Spathe anomaly: a small second spathe. (C) Front and back views of open inflorescence, with scar of atypical second spathe on the peduncle. (D) Juvenile plant. (E) Developing inflorescence. (F) Fertile flower. (G) Stylar plate with stigma (left) and one stamen (right). (H) Mature infructescence, stylar plates detached toward the apical part. (I) Seeds. (J) Adult plant. M. Cedeño et al. 1481 (USJ). Image from Cedeño-Fonseca et al. (2020g).

FIGURE 63. Monstera obliqua. Adult plant growing in the forests around Manzanillo, Costa Rica. M. Cedeño et al. 2201 (USJ). Image from Cedeño-Fonseca et al. (2022).