SYNGONIUM PODOPHYLLUM
PROTOLOGUE: Syngonium podophyllum , published in Botanische Zeitung 9: 85 (1851). The protologue is reproduced below.
SYNONYMS:
HOMOTYPIC SYNONYMS: Syngonium podophyllum var. typicum Engl.
HETEROTYPIC SYNONYMS: Arum auritum Vell.; Pothos auritus Willd.; Syngonium affine Schott; Syngonium amazonicum Engl.; Syngonium decipiens Schott; Syngonium gracile (Miq.) Schott; Syngonium podophyllum var. multisectum Engl.; Syngonium poeppigii Schott; Syngonium riedelianum Schott; Syngonium ruizii Schott; Syngonium ternatum Gleason; Syngonium vellozianum Schott; Syngonium vellozianum var. decipiens (Schott) Engl.; Syngonium vellozianum var. latilobum Engl.; Syngonium vellozianum var. oblongisectum Engl.; Syngonium vellozianum var. poeppigii (Schott) Engl.; Syngonium vellozianum var. riedelianum (Schott) Engl.; Syngonium willdenowii Schott; Syngonium xanthophilum Schott; Xanthosoma gracile Miq.
DISTRIBUTION: Mexico to Trop. America: Belize, Bolivia, Brazil North, Brazil Northeast, Brazil Southeast, Brazil West-Central, Colombia, Costa Rica, Ecuador, El Salvador, French Guiana, Guatemala, Guyana, Honduras, Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Southeast, Mexico Southwest, Nicaragua, Panama, Peru, Suriname, Trinidad and Tobago, Venezuela, Venezuelan Antilles.
DISTRIBUTION NOTE: Belize: Belize, Cayo, Toledo Costa Rica: Alajuela, Guanacaste, Heredia, Limón, Puntarenas El Salvador: La Libertad Guatemala: Guatemala Honduras: Atlántida, Colón, Copán, Cortés, Gracias a Dios, Olancho, Santa Bárbara Mexico: Campeche, Chiapas, Guerrero, Hidalgo, Morelos, México State, Nayarit, Oaxaca, Puebla, Querétaro, San Luis Potosí, Tabasco, Tamaulipas, Veracruz Nicaragua: Boaco, Chontales, Granada, Jinotega, Matagalpa, North Caribbean Coast, Nueva Segovia, Rivas, Río San Juan, South Caribbean Coast Panama: Bocas del Toro, Coclé, Colón (Panama), Darién, Panamá Province Peru: Amazonas (Peru), Junín, Loreto, San Martín Venezuela: Amazonas (Venezuela), Delta Amacuro, Mérida, Trujillo, Táchira, Zulia iNaturalist: Antioquia, Chiapas, Puntarenas, Rio de Janeiro, São Paulo, Tabasco, Veracruz.
SPECIES DESCRIPTION:
Nomadic vine to 6 m; juvenile plant with stems slightly glaucous; petioles sheathed 0.5–0.9 their length; blades simple, cordate, 7–14 cm long, becoming sagittate or hastate, acuminate at apex, anterior lobe somewhat constricted at the base, posterior lobes usually more or less triangular, directed downward or prominently outward; blades on climbing plants 12–27 cm long. Adult plants with stems sometimes glaucous; sap milky; internodes 2.8–14.5 cm long, 0.5–3.5 cm wide (dry). Leaves with petioles 15–60 cm long, sometimes glaucous, sheathed about 2/3 their length (sheath free-ending), rounded to obtusely angular above sheath; blades pedatisect, the surface dark green above, pale below (sometimes glaucescent in South America); leaflets 3–11, united to free; lowermost leaflet variously auriculate at the base, auricles oblong to oblong-elliptic to broadly elliptic; median leaflet obovate to broadly elliptic, abruptly acuminate at apex, broadly or narrowly decurrent at base, 16–38 cm long, 6–17 cm wide; rachis usually angular on blades with more than 3 segments; primary lateral veins 3–4(7) per side on the median leaflet, sunken above, prominently raised beneath; collective veins 2 or 3; tertiary veins all distinct.⁴
INFLORESCENCE:
Inflorescences 4–11 per axil; peduncle sometimes glaucous, somewhat compressed laterally, erect and usually less than 9 cm long at anthesis, pendent, to 13 cm long in fruit; spathe 9–11 cm long; spathe tube sometimes glaucous, narrowly ovoid to ellipsoid, 3–4 cm long, 1.8–2.0 cm diam., green inside and out; spathe blade greenish white to creamy white or sometimes yellow (in South America) (sometimes green outside and creamy white inside), 6.0–7.5 cm long, 3–5 cm wide, long-cuspidate at the apex; spadix 5–7 cm; pistillate portion 1–2 cm long, 6–9 mm diam., greenish cream, the flowers irregularly 5- or 6(7)-sided, adherent, the stigma discoid-capitate, sometimes 2- or 3-lobed; staminate portion 4–7 cm long, 7–15 mm diam., cream, the synandrium with anthers usually 4, cross-shaped, 3.5–4.0 mm wide, partially or completely fused. Infructescences red to reddish orange or yellow (rarely brown) at maturity; syncarp ovoid, brownish, scruffy with darker brown flecks, 3.0–5.5(7.0) cm long, 1.5–3.5 cm wide; seeds many, ovoid, 7–11 mm long, 5–7 mm wide, black or brown (white in the Cordillera del Cóndor material¹⁰), enveloped in a soft, grayish, sweet, pulpy mesocarp. It has been collected in flower and fruit throughout the year.⁴
ECOLOGY:
It is found principally on the Atlantic slopes in Mexico but commonly extends to the Pacific slope in Guatemala, Costa Rica, and Panama. It ranges from sea level to usually less than 1100 m and is more abundant below 750 m, especially between 100 and 500 m. In Central America, it is most frequent in regions of Tropical moist forest but also occurs in Premontane wet forest and Tropical wet forest life zones. It is mostly replaced by Syngonium macrophyllum in Tropical wet forest life zones.⁴ altitude: 0–750 m
ETYMOLOGY:
From Greek pous (podos), "foot," and phyllon, "leaf," referring to the pedate leaf blade of the adult plant, whose segments spread like the toes of a bird's foot. Schott published the name in 1851.²
NOTES:
1. Syngonium podophyllum is a member of section Syngonium. It and Syngonium macrophyllum are often difficult to separate where they occur together in wetter parts of Tropical moist forest and in Premontane wet forest life zones, but Syngonium macrophyllum is usually distinguishable by its much larger vegetative and fertile parts, its smoother, thicker blades, which tend to dry brown rather than greenish as in Syngonium podophyllum, and by its ovate-cordate juvenile blades. The morphological variation in the species is great. Mexican plants may have up to 11 leaflets (usually 9), have leaflets often more widely separated and have stems, peduncles and spathe tubes glaucous, whereas Panamanian populations generally have mostly 3–5 (sometimes 7) leaflets with the lowermost leaflet often conspicuously auriculate. Unusual variation is also represented in collections from Darién Province, Panama. Here the auricles of the lateral leaflets are frequently obovate and scarcely pinched-off rather than more or less oblong and usually conspicuously pinched-off as is typical of most Central American populations. These Darién populations most closely resemble typical material of what was previously considered Syngonium vellozianum. Infructescences in Mexico are commonly bright red whereas those in Panama and in South America are generally yellow to orange or red-orange. In Central America, Syngonium podophyllum is most closely related to and confused with Syngonium angustatum. The two species occur together in similar habitats throughout much of their range in Central America, and according to Birdsey (1955) they may hybridize. (See the Key for characters used in separating the two species.) Syngonium podophyllum may also be confused with Syngonium neglectum in its vegetative condition. In the field, Syngonium podophyllum can be distinguished from Syngonium neglectum by its glaucous stems. Although the species tends not to have glaucous stems in the southern part of its range, there is no confusion with Syngonium neglectum, which is restricted to Mexico. ⁴
2. Naturalized far outside its range: abundant on the Universitas Indonesia campus in West Java, reported naturalized in Singapore and rated a high-risk weed in Hawaiʻi.⁶ Escaped plants in Florida and Hawaiʻi have been found in fruit, with about a dozen pea-sized seeds in white, faintly sweet pulp.⁸,⁹
STORY:
STORY TITLE: The arrowhead vine that got away
Syngonium podophyllum is the most widespread and variable species in the genus, ranging from San Luis Potosí and Veracruz in Mexico to the Guianas, Brazil and Bolivia, mostly below 750 m and most often in Tropical moist forest. Mexican plants can carry up to eleven leaflets on glaucous stems; Panamanian ones usually have three to five, the lowest often conspicuously eared. Infructescences ripen bright red in Mexico and yellow to orange in Panama and South America.⁴
It is also the Syngonium that almost everyone has grown, and it has escaped on three continents. In Java it grows abundantly across the campus of Universitas Indonesia, in urban forest and on unused land around buildings; the same paper records it as naturalized in Singapore and rated a high-risk weed in Hawaiʻi.⁶ Research-grade wild observations on iNaturalist now come in the hundreds from Florida, Texas, Puerto Rico, Taiwan, Hong Kong and eastern Australia.³
Whether escaped plants set seed has been debated among growers for years. Croat's view, given on the Aroid-L list in 2007, was that most Syngonium in cultivation in North America are never pollinated, and that even in the wild ripe fruit is seldom seen because animals take it as soon as it is ready.⁷ Yet Julius Boos, in May 2002, described vines climbing cypress trunks near the Everglades in Florida whose spathe tubes had turned bright red: inside was a smooth fused mass of berries under a thin patterned skin, white flesh around about a dozen pea-sized seeds, faintly sweet and reminiscent of Monstera deliciosa. The seeded infructescences sat several internodes below seedless ones, and he inferred two flowering flushes a year, the cool-season flowers going unpollinated.⁸ Five years later he recalled collecting a large quantity of ripe seed from the same kind of stand, fifteen to twenty feet up, for the aroid seed chemist Vic Soukup,⁷ and in Hawaiʻi a fallen infructescence in Moanalua Valley yielded sweet white pulp around black seeds, along with half an hour of burning from the calcium oxalate.⁹
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Syngonium podophyllum
2. Botanische Zeitung 9: 85 (1851) — protologue.
3. iNaturalist: Syngonium podophyllum
7. Croat, T.B. & Boos, J. 2007. Syngonium setting seed in S. Florida. Aroid-L, 26–28 March 2007
8. Boos, J. 2002. Syngonium fruit! Aroid-L, 8 May 2002
9. Hernandez, J. 2007. Syngonium. Aroid-L, 27 August 2007
10. Delannay, X. & Croat, T. B. (2021). Florula of Araceae from the Cordillera del Cóndor (Ecuador and Peru). Aroideana 44(2).
Additional photos by David Scherberich
Additional photos from iNaturalist by Dana Lee Ling, isatuccilli, Mauricio, 謝忠良, sea-kangaroo and Rigoberto Pantoja