MONSTERA DELICIOSA
PROTOLOGUE: Monstera deliciosa Liebm., published in Videnskabelige Meddelelser fra den Naturhistoriske Forening i Kjøbenhavn 1849: 19 (1849). The protologue is reproduced below.
SYNONYMS:
HOMOTYPIC SYNONYMS: Tornelia fragrans Gutierrez ex Schott
HETEROTYPIC SYNONYMS: Monstera borsigiana K.Koch; Monstera deliciosa var. borsigiana (K.Koch) Engl.; Monstera lennea K.Koch; Philodendron anatomicum Kunth & C.D.Bouché; Philodendron fenestratum Linden; Philodendron pertusum Kunth & C.D.Bouché
OTHER NAMES: Harpón (Guatemala); Piñanona (Mexico)
DISTRIBUTION: Mexico (Veracruz, Oaxaca, Chiapas) to Guatemala: Chiapas, Guatemala, Mexico Gulf, Mexico Southeast, Mexico Southwest, Oaxaca, Veracruz.
DISTRIBUTION NOTE: Mexico: Chiapas, Oaxaca, Tabasco, Veracruz iNaturalist: Jalisco.
SPECIES DESCRIPTION:
Robust to massive herb, terrestrial or nomadic vine, appressed-climbing habit. Seedlings: bearing foliage leaves. Juvenile plants: root climbers; stems brown to grayish, smooth or warty, cylindrical; internodes 7–12 cm long, 1–2 cm diam.; petiole distinct, dark green, smooth, 14–17 cm long, sheathed up to half their length; petiole sheath semi-deciduous; blades ovate to lanceolate, cordate at base, acuminate, coriaceous, 15–23 × 14–20 cm, not appressed to the phorophyte; fenestrations absent. Adult plants: root climbers; stems green to dark green, becoming grayish brown with age, smooth, cylindrical, internodes 1–9 cm in long, 3–8 cm diam., 0.3–1.6 times as long as wide; anchor roots whitish; feeder roots dark brown; petiole light green, warty or smooth, 40–110 cm long, sheathed up to half their length; petiole sheath deciduous; unsheathed portion flattened and winged adaxially, convex abaxially; geniculum warty, flattened adaxially and convex abaxially, 2–5 cm long; blades ovate to lanceolate, cordate to subcordate at base, acuminate, coriaceous, drying grayish or yellowish, 40–75(112) × 40–55(88) cm, 1.0–1.1 times longer than wide, decurrent-undulate over the geniculum, with 4–6 undulations of 5–7 mm wide; midrib flattened adaxially, convex abaxially, drying yellowish or blackish on both surfaces; primary lateral veins 6–11 per side, prominent on both surfaces, departing midrib at 85–90°, drying yellowish, black or dark brown; secondary veins slightly prominent and reticulate; collective veins not visible; fenestrations round or ovoid, numerous, extending along the blade and near the midrib; margins pinnatilobed, 4–10 lobes per side, sometimes with a vein that runs along the margin which reaches the middle of the blade, occasionally marginal fenestrations can break the margin and cause a bifid lobe.⁴
INFLORESCENCE:
Inflorescences on ascending stems, 2–5 simultaneously at flowering time, arranged in the leaf axils or into cataphylls; peduncle 12–25 cm long, 2.5–3.0 cm diam., tuberculate; spathe short acuminate, bluish-green during development, yellowish externally and cream internally with revolute margins and closed (at apex) at anthesis, deciduous after anthesis, 12–23 × 7–13 cm, up to 5 cm longer than the spadix; spadix creamy-yellowish (both during development and at anthesis), 10–20 cm long, 2.5–3.0 cm diam., 3.4–5.8 times longer than wide; basal sterile flowers with a yellow stigmatic secretion, 5–8 mm long; fertile flowers 7–10 mm long; stamens 1.2–9.5 mm long, with laminar filaments; anthers 2.0–2.7 mm long; ovary quadrangular in longitudinal section, ribbed, 5–8 × 5–7 mm; style compressed and hexagonal, 2.5–3.0 × 4–7 mm; stigmatophore slightly cupuliform, 0.3–0.4 mm long; stigma circular and sunken, with transparent secretion; berries with a light green stylar cap during development, mature stylar cap yellowish; pulp white; seeds dark green, 5–10 mm long.⁴
ECOLOGY:
Monstera deliciosa is known in Southern Mexico (Chiapas, Oaxaca, Tabasco, and Veracruz) and Guatemala, at elevations of 90–2000 m, in Premontane rain forest, Tropical moist forest and Tropical wet forest life zones. Flowering March, April, and May. Fruit is present all year.⁴ Thomas B. Croat wrote in 2007 that he had seen the large, heavily perforated form of Monstera deliciosa only at Uspanapa in southern Mexico, growing on limestone outcrops.¹¹
ETYMOLOGY:
Latin deliciosa, "delicious," in reference to the sweet edible fruits.⁶
NOTES:
1. The species is a member of sect. Tornelia and is distinguished by its smooth stem with short internodes, petioles subequal to or longer than the blades, ovate cordate, moderately coriaceous leaves with conspicuous secondary veins, peduncles about as long as spadix and a spadix that remains green, never as dark as in Monstera tacanaensis. Monstera deliciosa was considered a widely distributed species in Central America. However, through fieldwork in Costa Rica and Panama this species is found only in cultivated form. The natural populations that were considered for Costa Rica and Panama with hanging habit and not robust plants have been considered as Monstera tacanaensis Matuda. This species was established as a synonym by Madison in 1977, but Cedeño-Fonseca et al. (2020c) have considered that these individuals belong to a different species and are not part of the Monstera deliciosa variation. To corroborate this, Cedeño-Fonseca et al. (2020c) carried out fieldwork in the type locality of Monstera tacanaensis in the Volcán Tacaná region Mexico and Guatemala are the only regions where Monstera deliciosa has been collected naturally. The other collections in Central Amerca indicate that they are collections of cultivated plants. Monstera deliciosa is a species that is distributed in different habits in Mexico, dry forests, humid forests and cloud forests, possibly being the species with the greatest diversity of growth habitats. For more details about the taxonomic comments and nomenclatural note see Cedeño-Fonseca et al. (2022).⁴
STORY:
STORY TITLE: Twice discovered, still unexplained
For a century and a half after 1693 Europe knew a single Monstera, the West Indian plant now called Monstera adansonii, grown in botanical gardens under the Linnaean name Dracontium pertusum.⁶ In the 1840s Monstera deliciosa was found twice over: Liebmann met it in Mexico and Warszewicz in Guatemala, and each shipped living plants home, to Copenhagen and to Berlin.⁶ The introduction was a horticultural triumph. Cultivation spread across Europe within years, a rush to find and name further species followed, and by 1860 the first monograph of the genus already carried 35 names.⁶
The perforations that made the plant famous have been argued over since 1892, when H. W. King proposed that the holes let rainwater drip through to the ground, an idea later dismissed as fanciful.⁷ The 1977 revision suggested instead that a dissected blade sheds heat by convection, drawing on lacerated banana leaves, though banana is a full-sun pioneer and Monstera lives in shade.⁷ A camouflage reading followed in 2006, and in 2013 a model proposed something different again: in an understory lit by brief, unpredictable sunflecks, a fenestrated leaf evens out a plant's carbon gain from week to week, reducing the variance in growth rather than raising its average.⁷ That model was offered as a testable hypothesis, and the field test is still to come.⁷
Even the fruit keeps a small mystery. Unripe fruit pricks the mouth, and the 1977 revision left it unclear whether the culprit is the needle-like raphide crystals or the trichosclereids of the stylar cap.⁶ Ripe fruit does not suit everyone either, according to two writers on the Aroid-L mailing list. Leland warned that some people are sensitive to the calcium oxalate even in fully ripe fruit,¹² and D. Christopher Rogers wrote that some people who eat his ripe Monstera deliciosa fruit report a strong tingling, pin-pricking feeling on the lips, while others, eating fruit from the same plant, do not.¹³ Leland named calcium oxalate and Rogers suggested the needle-like crystals, and the cause is still unsettled.
Its pollination has never been watched in the wild. Stingless Trigona bees were the only visitors on record, so for decades they were supposed to be the pollinators.⁸ A message to the Aroid-L mailing list from Sarawak, where Monstera deliciosa sets viable seed regularly, named a melolonthin scarab, tentatively identified as Apogonia pygidialis Ritsema, as the main visitor and possibly the pollinator; the same beetle visits native aroids, notably Homalomena.¹⁴ When Monstera obliqua was followed through a full cycle in French Guiana, all 242 insects that entered the spathe were one species of nitidulid beetle.⁸ In Monstera lentii in Costa Rica the pollinator was again a nitidulid beetle, and the stingless bees present were robbing pollen.⁹ The most cultivated aroid in the world is still waiting for its own study.
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Monstera deliciosa Liebm.
2. Videnskabelige Meddelelser fra den Naturhistoriske Forening i Kjøbenhavn 1849: 19 (1849) — protologue.
3. iNaturalist: Monstera deliciosa
7. Muir 2013. How did the Swiss cheese plant get its holes? The American Naturalist 181: 273–281
10. Cedeño-Fonseca, Díaz Jiménez, Zuluaga & Blanco 2020. A comparison of Monstera deliciosa and M. tacanaensis, with comments on Monstera section Tornelia (Araceae). Aroideana 43(1&2): 32–73.
11. Aroid-L mailing list, Tom Croat, February 5th, 2007
12. Aroid-L mailing list, Leland, July 6th, 2008
13. Aroid-L mailing list, D. Christopher Rogers, August 6th, 2009
14. Aroid-L mailing list, Peter, August 11th, 2009
Additional photos by Patrick Blanc
Additional photos by David Scherberich
Additional photos from iNaturalist by Michael Vicente Riofrio, Andy Jones, Manuel Cortina, Maliemociones, Daniel Cavallari, Milo Pyne and Elsa Liu
Additional photo from Wikimedia Commons by Raffi Kojian
