MONSTERA MOLINAE
PROTOLOGUE: Monstera molinae Grayum, published in Phytologia 82: 48 (1997).
Monstera molinae Grayum, spec. nov. Type: COSTA RICA. Guanacaste: Parque Nacional Rincón de la Vieja, the SE slopes of Volcán Santa María, above Estación Hacienda Santa María, 10° 47’ N, 85° 18’ W, 900–1200 m, 27–28 Jan 1983, G. Davidse, L.D. Gómez, M. Sousa, C.J. Humphries, N. Garwood, R. Hampshire, & M. Gibby 23344 (HOLOTYPE: CR-97202!; Isotype: MO!).
DISTRIBUTION: Costa Rica to C. Panama: Costa Rica, Panama.
DISTRIBUTION NOTE: Costa Rica: Guanacaste iNaturalist: Alajuela, Guanacaste, Heredia.
SPECIES DESCRIPTION:
Nomadic vine, appressed-climbing and pendent habit. Seedlings: filiform. Juvenile plants: root climbers; stems dark green, smooth, cylindrical; internodes 4–6 cm long, 3–5 mm diam.; petiole distinct, dark green, smooth, 6–10 cm long, sheathed to base of the geniculum; petiole sheath persistent; blades obovate, subcordate to truncated at base, acuminate at apex, coriaceous, 7–10 × 5–8 cm, slightly appressed to the phorophyte; fenestrations absent. Adult plants: root climbers with free lateral branches; stems beige to light brown, smooth, cylindrical or dorsoventrally compressed and slightly sulcate; internodes 2–14 cm long, 0.5–0.6 cm diam., 4–23 times longer than wide; anchor roots whitish; feeder roots dark brown; petiole light green, smooth, 10–25 cm long, sheathing to base of the geniculum or base of the leaf blade; petiole sheath persistent or semi-persistent; geniculum smooth, sunken adaxially, convex abaxially, 6–15 mm long; blades ovate, oblique, cordate to subcordate or obtuse at base, acuminate at apex, coriaceous, drying reddish with black or brownish dots, 10–30 × 11–25 cm, 1.0–1.4 times longer than wide, decurrent on the geniculum, decurrent portion 1–2 mm wide; midrib ribbed adaxially, convex abaxially, drying dark or reddish brown on both surfaces, primary lateral veins 7–10 per side (occasionally 2 of them can emerge at once and then spread to the margin), strongly sunken adaxially, prominent abaxially, departing midrib at 75–80°, drying black up to the medial part; secondary veins prominent, reticulate towards the margin; collective veins not visible; fenestrations absent; margins entire or pinnatilobed with 2–4 lobes per side.⁴
INFLORESCENCE:
Inflorescences on free lateral shoots and ascending stems, 1–5 simultaneously at flowering time, arranged in the axils of the leaves; peduncle smooth, 4–5 cm long; spathe obtuse to short acuminate, light green during development, yellowish green externally and white internally at anthesis, completely open at apex, deciduous post-anthesis (tearing in several parts), 8–12 × 5–9 cm, up to 1 cm longer than the spadix; spadix white during development, cream at anthesis, 7–15 cm long, 2–3 cm diam., 3.2–3.4 times longer than wide; basal sterile flowers 4–5 mm long, with an orange stigmatic secretion; fertile flowers 4–7 mm long; stamens 1–2 mm long, with laminar filaments; anthers 1–3 mm long, the filaments do not exceed the styles at anthesis; the flowers on the spadix are separated, allowing exposure of the thecae; ovary square in longitudinal section, ribbed, more slender than style, 2–4 × 2–3 mm; style square, cylindrical or hexagonal, 3–5 × 3–4 mm; stigma linear, cleft on style, black at anthesis; berries with a creamy stylar cap during development, mature stylar cap moss-green; pulp grayish; seeds light-brown with pale dots, elongated, 5–10 mm long.⁴
ECOLOGY:
Monstera moliniae is endemic to Costa Rica (Atlantic slope and near Continental Divide, Cordilleras de Guanacaste, Tilarán and Central), from sea level to more than 1200 m, in Tropical wet forest and Tropical wet forest transition to Premontane wet forest life zones. Flowering has been recorded in January to March, May, and November, and fruiting in June and December.⁴
ETYMOLOGY:
Named in honor of Antonio Molina R. (EAP), dean of Honduran botanists, who made the first known collection on 21 February 1966.²
NOTES:
1. The species is a member of sect. Marcgraviopsis characterized by its hemiepiphytic vine-like habit, petioles sheathed to near base of blade with a deciduous sheath, broadly ovate to elliptical blades which are broadly cuneate to rounded or truncate at base, deeply pinnatifid with 2–5 pinnae on at least one side and lacking perforations, 4–8 primary lateral veins per side, peduncles shorter than spadix with the spathe green to olive-green outside, creamy white within. Monstera molinae is most easily confused with Monstera spruceana which differs in being appressed-climbing with the petioles more than 20 cm long and the blades generally more than 30 cm long as well as by the larger spadices which are 11 to 18 cm long at anthesis. In contrast Monstera molinae has a more scandent habit, petioles less than 20 cm long, blades less than 30 cm long and the spadices about 5–11 cm long. The populations of Monstera molinae are distributed only in the Caribbean slope and are located mainly in primary forests. Adult plants develop hanging reproductive stems. In La Tirimbina Biological Station, the reproductive hanging stems reach the ground, eventually becoming creepers (Cedeño-Fonseca et al. 2022).⁴
2. Conservation status: Monstera molinae is protected in the Estación Biológica La Selva, Reserva Biológica La Tirimbina, Parque Nacional Guanacaste, Parque Nacional Rincón de la Vieja, Parque Nacional Volcán Tenorio and Parque Nacional Braulio Carrillo.⁵
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Monstera molinae Croat & Grayum
2. Phytologia 82: 48 (1997) — protologue.
3. iNaturalist: Monstera molinae
Additional photos from iNaturalist by Marcel Esquivel, Leon, njweess, Makena, Noah Doré and Oliver Ingold