MONSTERA PANAMENSIS

PROTOLOGUE: Monstera panamensis M.Cedeño & O.Ortiz, published in Journal of Plant Taxonomy and Geography (Webbia) 78: 111 (2023).

Monstera panamensis M.Cedeño & O.Ortiz, sp. nov. Type: Panama, Coclé: Parque Nacional Omar Torrijos Herrera. El Copé, carretera que va hacia La Rica, 771 m, 30 Sep 2019, O.O. Ortiz & M. Cedeño 3950 (holotype PMA!; isotype MO!).

DISTRIBUTION: Panama: Panama.

SPECIES DESCRIPTION:

Robust nomadic vine, appressed-climbing and pendent habit. Seedlings: filiform. Juvenile plants: root climbers; stems dark green, smooth, cylindrical; internodes 2–6 cm long, 0.5–10 mm diam.; petiole not visible, dark green, smooth, 3–5 cm long; blades obovate, subcordate at base, acuminate at apex, coriaceous, 5–12 × 6–10 cm, appressed to the phorophyte; fenestrations present, usually 1 that breaks at the margin. Adult plants: root climbers with free lateral branches; stems dark-green or brown, cylindrical, smooth; internodes 3–15 cm long, 2–4 cm diam.; anchor roots light brown; feeder roots dark brown; petiole light-green, smooth, 17–30 cm long, sheathed to base of the geniculum or to base of the blade; petiole sheath deciduous; geniculum smooth, sunken adaxially, convex abaxially, 2–4 cm long; blades lanceolate or ovate to sub-orbicular, obtuse or truncate at base, obtuse to slightly acuminate at apex, coriaceous, 20–45 × 17–20 cm, decurrent on the geniculum; midrib ribbed adaxially, convex abaxially; primary lateral veins 7–10 per side, sunken adaxially, prominent abaxially; collective veins not visible; fenestrations present in transition to adult plants and in some adult leaf blades; margins pinnatilobed, 2–6 lobes per side, 1.5–5 cm wide, 1–2 veins per lobe.²

INFLORESCENCE:

Inflorescences: in hanging stems, 1 solitary at flowering time, arranged in the axils of the leaves; peduncle smooth, up to 6 cm long; spathe unknown in development and anthesis; spadix unknown during development, unknown at anthesis, 13–15 cm long, 3–4 cm diam.; basal sterile flowers 5–7 mm long; fertile flowers 7–10 mm long; stamens unknown; anthers unknown; ovary rectangular in longitudinal section, ribbed, more slender than style, 4–6 × 2–3 mm; style hexagonal and strongly projected, slender and cylindrical distally, 4–5 × 3–4 mm, stigma linear; berries with a green stylar cap during development, mature stylar cap unknown; pulp unknown; seeds unknown.²

ECOLOGY:

This species is endemic to Panama, at elevations of 0–850 m, on the Caribbean and Pacific slope. It occurs in Tropical wet forest and Premontane rain forest life zones, in primary forest. Flowering time is unknown but fruiting was recorded in September and November.²

ETYMOLOGY:

The epithet is drawn from the Republic of Panama, and alludes to the species’ origin.²

NOTES:

1. Monstera panamensis is most easily confused with Monstera molinae and Monstera spruceana, but it differs from Monstera molinae in having larger leaves on adult plants (20–45 cm to long vs. 10–30 cm long), pinnatilobed and with perfora- tions (vs. completely pinnatilobed without perforations), and the style hexagonal, distally slender and cylindrical, and strongly projecting, (vs. a distally square, cylindrical or hexagonal projecting style). It differs from Monstera spruceana in having inflorescences on free hanging stems (vs. on attached ascending stems), the petiole completely smooth (vs. smooth or warty), the petiole sheath deciduous without fibrous remnants (vs. deciduous with fibrous frag- 113 Three new species and a new record of Monstera Adans. sect. Marcgraviopsis ments), and style hexagonal and strongly projecting and cylindrical distally (vs. style hexagonal and not raised).²

2. The species is a member of section Marcgraviopsis. It is distinguished by its lengthy internodes up to 15 cm long, the pinnatilobed adult leaf blade, the smooth petiole, sheathed up to the base of the geniculum, short peduncles (<6 cm), long spadices (14–15 cm), and a hexagonal, strongly projecting, and distally cylindrical style. J.P Folsom 6207 (MO) was long confused with Monstera molinae. However, due to differences that could be observed in the flowers in the herbarium sample, fieldwork was carried out to examine the populations in their natural state, with the result that this collection is here redetermined as Monstera panamensis. The majority of populations of Monstera panamensis from the Caribbean lowlands have not been seen with reproductive structures.²

REFERENCES:

1. Plants of the World Online, Royal Botanic Gardens, Kew — Monstera panamensis M.Cedeño & O.Ortiz

2. Journal of Plant Taxonomy and Geography (Webbia) 78: 111 (2023) — protologue.

Additional photos from iNaturalist by Mabelin and Oliver Ingold