SYNGONIUM TRIPHYLLUM
PROTOLOGUE: Syngonium triphyllum , published in Annals of the Missouri Botanical Garden 68: 642 (1982).
Syngonium triphyllum Birdsey ex Croat, sp. nov. Caudex 1–2.5 cm diam.; lamina plerumque trisecta, saepe basi auricula conspicua spathulata; petiolus 11–50 cm longus, ad ⅔–⅘ longitudinalis usque vaginatus, apice acute triangulari; lamina media ovata ad oblonga-elliptica aut elliptica, aequilatera, 17–32 cm longa, lamina lateralis ovata-elliptica ad elliptica, fere aequilatera aut inaequilaterissima et basi auriculata, venis conspicue depressis. Inflorescentiae 1–3(–5); pedunculus 5–7 cm longus; spathae tubus anguste ellipsoideus, 4.5–6 cm longus, 2–2.5 cm diam., intra viridis pallide, extra rubus; spathae lamina oblonga-elliptica ad oblonga, albida, 8–9 cm longa, cucullata; spadix parte feminea 1.9–2.5 cm longa, stigmate sessili, cupulato. Type: Costa Rica, Heredia, near Puerto Viejo along the Río Sucio, 20 m, Croat 35675 (MO-2381577, holotype).
DISTRIBUTION: C. America to NW. Colombia: Belize, Colombia, Costa Rica, Honduras, Nicaragua, Panama.
DISTRIBUTION NOTE: Belize: Belize, Toledo Colombia: Chocó Costa Rica: Alajuela, Cartago, Heredia, Limón, Puntarenas, San José Honduras: Atlántida Nicaragua: Río San Juan, South Caribbean Coast Panama: Bocas del Toro, Chiriquí, Coclé, Colón (Panama), Panamá Province, Veraguas.
SPECIES DESCRIPTION:
Nomadic vine; juvenile plants at first with short internodes (5 mm or less), becoming scandent, not glaucous, green to greenish brown, turning brown with age; internodes to 17 cm long; petioles sheathed 4/5 or nearly their entire length, less than I0 cm long, sheath with margin crisped; blades inequilateral, elliptic, acuminate at apex, acute to obtuse and often inequilateral at base, sometimes weakly cordate, 6–23 cm long, 3–9 cm wide. Intermediate plants with petioles 14–28 cm long; blades entire and elliptic to oblong-elliptic or ovate-elliptic or becoming auricle-lobed at base, auricles held parallel to petiole, in later stages becoming more trisect, lobes oblong-elliptic, directed at nearly right angles to midrib. Adult plants with stems not glaucous, sometimes branched; internodes to 9 cm long, to 2.5–3.5 cm long on flowering portions, 1.0–2.5 cm diam., brown, matte, sometimes drying flaky, sometimes with sharp longitudinal wrinkles. Leaves with petioles 11–50 cm long, sheathed 2/3–4/5 their length or more, unsheathed portion sharply triangular with lateral margins sharply raised; blades usually trisect but frequently with a conspicuous spatulate auricle at base, auricle sometimes to 15 cm long, blade thus appearing almost 5-pedatisect; leaflets free, semiglossy above, dark green, drying dark, lower surface slightly paler; median leaflet ovate to elliptic or oblong-elliptic, equilateral or nearly so, 17–32 cm long, 6–14 cm wide, short-acuminate at apex, cuneate or obtuse at base; lateral leaflets of well-developed blades 15–28 cm long, 4–11 cm wide, ovate-elliptic to elliptic, nearly equilateral to very inequilateral and variously auriculate at base, auricles oblong to spatulate to oblong-elliptic, 6–16 cm long; primary lateral veins 10–16 per side, scarcely more prominent than the numerous interprimary veins; primary, major secondary veins and collective veins prominently sunken above, prominently raised on lower surface, smaller veins clearly visible when fresh; reticulate veins often very close and fine on drying, collective veins 3–12 cm from margin, moderately straight or broadly arching between primary lateral veins.³
INFLORESCENCE:
Inflorescences 1–5 per axil, usually 1–3, most frequently 1 or 2; peduncle erect, 5–7 cm long in flower, 8–13 cm long and pendent in fruit; spathe ca. 14 cm at anthesis; spathe tube narrowly ellipsoid, 4.5–6.0 cm long, 2.0–2.5 cm diam., pale green outside, red inside to near apex; spathe blade oblong-elliptic to oblong, white on both sides, short cuspidate and weakly cucullate at apex, 8–9 cm long, ca. 3.5 cm diam. (to 5 cm wide when flattened); spadix 7.9–12.5 cm long pistillate portion of spadix 1.9–2.5 cm long (fresh) (1.0–1.8 cm long dry), 7–13 mm diam., pale yellowish white, flowers irregularly 4-sided, stigma sessile, cup-shaped; staminate portion of spadix 6–10 cm long, 1.0–1.5 cm diam., clavate, gradually attenuate toward sterile flowers, fertile staminate flowers 4-staminate, anthers partially or completely fused, synandrium truncate or slightly rounded at apex, staminate sterile flowers slightly longer than adjacent fertile staminate flowers and much longer than pistillate flowers, 4–6-sided to ellipsoid or subglobose; spathe tube becomes rolled backward along its lateral margins and fleshy white spadix is prominently displayed against bright red interior of spathe tube. Infructescences oblong-elliptic, green tinged with purple, becoming violet purple on outside, inner surface bright red; syncarp oblong-ellipsoid, 6–8 cm long, 3.5–4.0 cm diam.; mesocarp white, fleshy, sweet; seeds black, irregularly ovoid to ellipsoid, 5–8 mm long, 4–6 mm wide. Inflorescences have been found from February through May and in October and November. Immature fruits are known from March to October with nearly mature fruits in May, June, and July.³
ECOLOGY:
It also occurs on the Pacific slope at Palmar Norte in Puntarenas Province, Costa Rica, and on the Burica Peninsula between Panama and Costa Rica as well as in Colombia (Chocó), generally in primary forest. It is probably restricted to Premontane wet forest and Tropical wet forest life zones below 1000 m.³ altitude: 1000 m
ETYMOLOGY:
From Greek tri-, "three," and phyllon, "leaf," referring to the trisect leaf blades of the adult plant. The name was proposed by Monroe Birdsey and published by Croat in 1981.²
NOTES:
1. Birdsey (1955) reported the species to be in virgin areas in Honduras but from disturbed areas in Costa Rica. I have always found it growing in virgin forest or in disturbed remnant virgin forest but never in a weedy situation. The species is a member of sect. Syngonium and is characterized by having the petiole cross-sectional shape which has an acute medial rib and conspicuously raised lateral margins and blackish-drying leaf blades with numerous conspicuously sunken veins as well as by having juvenile blades with small, more or less spatulate lateral lobes that are directed laterally. Other distinguishing characters include having moderately few inflorescences, a sessile, cup-shaped stigma, a cucullate spathe blade, and a spathe tube that is reddish inside, bright red while in fruit. According to Birdsey (1955) the pollen of Syngonium triphyllum is unique for Syngonium with the ‘'surface almost completely covered with more or less orbicular knobs.''³
2. Proposed in Monroe Birdsey's unpublished 1955 Harvard thesis and finally published by Croat in his 1981 revision, as Syngonium triphyllum Birdsey ex Croat.³
3. The species Thomas Ray used to illustrate foraging behavior in climbing aroids at La Selva and Finca El Bejuco: when the palm trunk supporting a climbing shoot was cut, the shoot switched to a flagellar form, its internodes narrowing to 4.2 mm and lengthening to 20.8 cm, and switched back to climbing form as soon as it was trained onto another tree.⁴
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Syngonium triphyllum
2. Annals of the Missouri Botanical Garden 68: 642 (1982) — protologue.
Additional photos by David Scherberich