MONSTERA INTEGRIFOLIA
PROTOLOGUE: Monstera integrifolia Zuluaga & Croat, published in Phytotaxa 334: 6 (2018).
DISTRIBUTION: N. Costa Rica to W. Panama: Costa Rica, Panama.
DISTRIBUTION NOTE: Panama: Chiriquí.
SPECIES DESCRIPTION:
Nomadic vine, appressed-climbing. Seedlings: bearing foliage leaves. Juvenile plants: root climbers; stems dark green with white dots, cylindrical; internodes 2–8 cm long, 4–10 mm diam.; petiole distinct, dark green with white dots, smooth, 8–10 cm long, sheathed to base of the geniculum; petiole sheath deciduous or slightly persistent; blades lanceolate, truncate at base, acuminate at apex, 8–14 × 5–8 cm; not appressed to the phorophyte; collective veins visible; fenestrations absent. Adult plants: root climbers; stems dark green or yellowish, sometimes white-spotted, cylindrical; internodes 2–4 cm long, 1.4–2.0 cm diam., 1.4–2.0 times longer than wide; anchor roots and feeder roots dark brown; petioles dark green, whitish or with white dots, smooth, 10–30 cm long, sheathed to base of the geniculum; petiole sheath slightly persistent or deciduous with fibrous fragments; geniculum smooth with white dots, sulcate adaxially, convex abaxially, 1–3 cm long; blades lanceolate, cuneate or attenuate at base, acuminate at apex, coriaceous, 30–40 × 9–13 cm, 2.0–2.6(3.3) times longer than wide, slightly decurrent on geniculum, decurrent portion 1–2 mm wide, drying black with light brown dots; midrib ribbed adaxially, convex abaxially, primary lateral veins 5–10 per side, slightly sunken adaxially, prominent abaxially, departing midrib at 35–45°; secondary veins parallel across primary lateral veins, reticulate towards the margins; collective veins slightly visible; fenestrations absent or present, generally the fenestrations break at the margin; margins pinnatilobed with 2–3 lobes per side.⁴
INFLORESCENCE:
Inflorescences on ascending stems, arranged in the axils of the leaves; peduncle smooth, 6–15 cm long, 0.6– 1.2 cm diam.; spathe acuminate, light green during development, white to cream internally and green externally at anthesis, 15–18 × 8–9 cm, up to 8 cm longer than the spadix; spadix white (both during development and at anthesis), 8–10 cm long, 1.7–2.0 cm diam., 0.6–0.9 times as long as peduncle; basal sterile flowers 4–5 mm long; fertile flowers 4–5 mm long; stamens 2–4 mm long, with laminar filaments; anthers 1.5–2.0 mm long; ovary rectangular in longitudinal section, ribbed, 2–4 × 2–3 mm; style hexagonal, 2–4 × 3–4 mm; stigmatophore conical, 0.5–1.0 mm long; stigma circular with a yellowish stigmatic secretion; berries with a white stylar cap during development, mature stylar cap unknown; pulp unknown; seeds unknown.⁴
ECOLOGY:
Monstera integrifolia ranges from northern Costa Rica to western Panama at 1000– 2000 m, in Tropical wet forest or Premontane rain forest life zones. Flowering has been recorded in November. Fruiting in December.⁴
ETYMOLOGY:
From Latin integer, "entire," and folium, "leaf," referring to the entire, unlobed leaf blades.
NOTES:
1. The species is a member of sect. Monstera. It is distinguished by having narrow leaf blades with primary lateral veins that arise from the midrib at an angle of 35°, whitish and mottled petioles, with a petiolar sheath that disintegrates as fibrous residues, and flowers with a conical stigmatophore. It could be confused with Monstera anomala and Monstera standleyana. Monstera anomala never has fenestrate leaf blades and the flowers have an elongated style with a constriction in the middle. Monstera standleyana plants are usually more robust, have a columnar stigmatophore, and inhabit lower elevations (0‒1360 m). Monstera integrifolia is most similar to Monstera xanthospatha, a species endemic to the West and Central Cordilleras of Colombia at elevations between 1500–2300 m. Both species are small plants, flowering when they are less than 10 m tall, and inhabit montane cloud forests. Monstera integrifolia differs from Monstera xanthospatha in having shorter petioles and peduncules (9–14 vs. 13–25 cm), a longer spadix (8–10 vs. 5–7 cm), and flowers with raised styles (vs. flat).⁴
2. Conservation status: Monstera integrifolia is protected in the Parque Nacional Braulio Carrillo (región of Volcán Barba), and the Parque Internacional de La Amistad (Moravia, Chirripó).⁵
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Monstera integrifolia Zuluaga & Croat
2. Phytotaxa 334: 6 (2018) — protologue.
3. iNaturalist: Monstera integrifolia
Additional photos from iNaturalist by Oliver Ingold and Letizia Weichgrebe