Monstera minima Madison, Contr. Gray Herb.

Croat, Thomas B., Cedeño-Fonseca, Marco & Ortiz, Orlando O., 2024, Revision of Monstera (Araceae: Monsteroideae) of Central America, Phytotaxa 656 (1), pp. 1-197 : 116-117

33. Monstera minima Madison, Contr. Gray Herb. 207: 55. 1977.

Type: — PANAMA. Comarca de San Blas : trail E of Cangandí-Mandinga airport road, 2–5 mi. S of Mandinga airport, 27 Oct 1967. J.A. Duke 14758 (holotype MO-2051569 !) .

Nomadic vine, appressed-climbing habit. SEEDLINGS: unknown. JUVENILE PLANTS: unknown. ADULT PLANTS: root climbers; stems dark green, cylindrical; internodes 1–2 cm long, 0.5–0.7 cm diam., 2.8–3.0 times longer than wide; anchor and feeder roots black and corky; petiole 2–6 cm long, sheathed up to 3 cm before base of the geniculum, petiole sheath deciduous; unsheathed portion slightly terete; blades lanceolate, narrowly acute at base, long-acuminate at apex, dark green adaxially, slightly paler abaxially, 9–14 × 2.0–4.0 cm, 4.0–5.6 times longer than wide; primary lateral veins 4 or 5 per side, obscure or slightly sunken adaxially, slightly prominent and colorless abaxially, departing midrib at 35–45°, secondary veins not visible; fenestrations absent; margins entire. INFLORESCENCES on ascending stems, erect; peduncle light green, matte, 16–18 cm long, 3–4 mm diam.; spathe acuminate, ellipsoid, matte, creamy externally at anthesis; coriaceous, 6.5–7.5 × 3.2–4.0 cm; spadix white during development, creamy-yellow at anthesis, 4.4 × 3.5 cm; fertile flowers 2.5–4.5 mm long; stamens 0.5 mm long, with laminar filaments; anthers 0.3 mm long; style prismatic, moderately smooth, 6–7 mm diam.; stigma ellipsoid, deeply sunken with pale brown margins; berries with a green stylar cap; pulp white; seeds 0.4–0.5 mm diam.

Distribution and ecology: — Monstera minima is known only from the Caribbean coast of Panama (San Blas Province) and along the Pacific slope of northern Colombia (Chocó), at 50–150 m, in Tropical wet forest life zones. It occurs mainly in undisturbed forests in the lower 3 m of the forest, growing over shrubs and small trees in heavily shaded and humid conditions.

Phenology: —Known only from fruiting collection in October.

Discussion: —The species, a member of sect. Monstera , is characterized by its appressed-climbing habit, petioles sheathed throughout, lanceolate acuminate blades which are acute at base, inconspicuous primary lateral veins as well as by the long-pedunculate inflorescences with a creamy yellow spathe and white spadix.

Monstera minima is the smallest species in the section and it can easily be confused with other small species of the section, such as M. gambencis , M. obliqua and M. xanthospatha . Monstera minima differs from these species by the complete absence of perforated blades, peduncle longer than the flowering spadix and leaves (blade and petiole), and by the dark brown-drying leaves. In contrast to M. gambencis is endemic from La Gamba, Costa Rica, M. minima , M. xanthospatha is known only from the Cordillera Central and Cordillera Occidental of Colombia at 600–1700 m and M. obliqua is widespread, ranging from Costa Rica to French Guinea, Brazil and Bolivia.

Additional specimens examined: — PANAMA. San Blas: Trail east of Cangandi-Mandinga airport road, 2–5 miles south of Mandinga airport, 09°25’N 079°05’W – 09°27’N 079°05’W, 27 October 1967, James A. Duke 14768 ( MO!) . COLOMBIA. Chocó: Nuquí. Corregimiento de Arusí, Estación Biológica El Amargal , Jan 1999 – Apr 1999, J. Jácome 280 ( MO!) .