MONSTERA GENTRYI
PROTOLOGUE: Monstera gentryi Croat, M.Cedeño & O.Ortiz, published in Phytotaxa 514: 213 (2021).
Monstera gentryi Croat, M.Cedeño & O.Ortiz, sp. nov. Type: PANAMA. Chiriquí: Boquete, camino hacia el Cerro Pata de Macho, aproximadamente 1.0 km desde la entrada de Tree Trek, 1748 m, 23 Sept. 2019, O.O. Ortiz, M. Cedeño, Z. Samudio & Z. Serracín 3756 (holotype PMA!, isotypes MO!, USJ!, to be distributed).
DISTRIBUTION: W. Panama: Panama.
DISTRIBUTION NOTE: Panama: Chiriquí, Veraguas.
SPECIES DESCRIPTION:
Robust nomadic vine, appressed-climbing. Seedlings: bearing foliose leaves. Juvenile plants: root climbers; stems light or dark green, smooth; internodes 2–4 cm long, 3–7 mm diam.; petiole conspicuous, light green, smooth, 7–20 cm long, sheathed to base of the geniculum; petiole sheath persistent; blades lanceolate or ovate, subcordate to truncate at base, acuminate at apex, 8–16 × 3.5–4.8 cm, not appressed to the phorophyte; fenestrations present or absent. Adult plants: root climbers; stems dark or light green, drying light brown, smooth, cylindrical; internodes 1–4 cm long, 2–4 cm diam., 0.8–1.0 times as long as wide; anchor and feeder roots black; petiole light green or yellowish green, smooth, 34–50 cm long, sheathed to base of the geniculum; petiole sheath persistent; geniculum smooth, sulcate adaxially, convex abaxially, 2–4 cm long; blades narrowly ovate, asymmetrically rounded at base, sometimes obtuse on one side and rounded on the other, acuminate at apex, subcoriaceous, drying slightly dark brown to yellowish-brown, matte above, slightly paler, yellowish-brown and faintly glossy below, 33–40 × 15.8–20.5 cm, 1.7–2.4 times longer than wide, 0.9–1.1 times longer than petiole, decurrent on geniculum, decurrent portions 0.5–1.0 mm wide; midrib ribbed adaxially, convex abaxially, drying yellow-brown; primary lateral veins 13–25 per side, departing midrib at 60–75°, strongly sunken adaxially, prominent abaxially, drying yellow-brown; secondary veins parallel but becoming reticulated toward the margin; collective veins more or less visible; fenestrations present, usually comprising small sub-circular holes 0.6–2.5 cm long, located near the midrib, these often scattered among 7–9 larger oblong elliptical perforations, each 4.0–10.5 × 1.5–3.0 cm, these often extending from near the midrib to near the outer margin, the larger perforations often tearing through to the margins; margins entire or pinnatilobed (due to tearing of the perforations that extend to the margin), 2–6 lobes per side reaching the midrib, 1–6 cm wide.³
INFLORESCENCE:
Inflorescences produced on ascending stems; peduncle smooth, 15–30 cm long, 5–7 mm diam.; spathe long-acuminate, green-glaucous externally during development, green-glaucous or pinkish externally and light orange-yellow internally at anthesis, 14–20 × 5–10 cm, up to 10 cm longer than the spadix; apparently persistent after anthesis; spadix white during development, creamy-white at anthesis, 9.0–11.7 cm long, 1.3–1.8 cm diam.; basal sterile flowers 4–5 mm long; fertile flowers 5–6 mm long; stamens 1.5–6.0 mm long, with laminar filaments; anthers 1.5–3.0 mm long; ovary rectangular in longitudinal section, ribbed, 3–4 × 3.0–3.5 mm; style hexagonal, 1.5–2.0 × 3.0–3.5 mm; stigmatophore slightly columnar; stigma linear; basal sterile flowers 4–5 mm long; berries with creamy white stylar caps during development, mature stylar caps creamy; pulp white; seeds matte black, 4 × 5 mm.³
ECOLOGY:
Monstera gentryi is endemic to Panama, known only from western Panama between eastern Chiriquí Province (Cerro Pata de Mache), Gnäbe-Buglé Province (Cerro Colorado) and Veraguas Province at 900–1500 m, in Lower montane rainforest and Premontane rain forest life zones. Flowering has been recorded from December to April, July, September and October, and fruiting in January to May, August and September.³
ETYMOLOGY:
Named in honor of Alwyn Howard Gentry (1945–1993), an outstanding professional botanist who in the early 1970s collected some of the first herbarium specimens of this species (Gentry 3080 and 7434, MO).²
NOTES:
1. Monstera gentryi differs from the other species of the genus in Panama by its moderately slender stem, mostly short internodes, fully sheathed light brown-drying petioles with a persistent sheath, narrowly ovate, inaequilateral, heavily fenestrate blade with small, roundish perforations adjacent to the midrib and large, elongated ones extending nearly across the width of each half of the blades, as well as by the moderately long peduncle, the internally pinkish spathe, cylindroid spadix which is often creamy white at anthesis, about five times longer than wide and much shorter than the spathe.²
2. The species is member of sect. Monstera characterized by its moderately small stem, mostly short internodes; fully sheathed light brown drying petioles with a persistent sheath, narrowly ovate, inequilateral, heavily fenestrate blades with smaller holes along the midrib and large perforations extending nearly across the width of each half of the blades as well as by the moderately long peduncle, the pinkish spathe, cylindroid spadix which is often yellowish at anthesis, and is about 5 times longer than wide and much shorter that the spathe. Monstera gentryi is most easily confused with Monstera oreophila. That species differs in being less robust with more slender stems, leaves with less diverse perforations usually with only a few small holes and otherwise also with fewer large perforations. In addition, the upper blade surfaces of Monstera oreophila have the minor veins less prominent, scarcely raised with the intervening areas moderately smooth while the lower surface is evenly and prominently striate as well as densely granular. In addition, the spathe of Monstera oreophila is thinner and proportionately shorter in relation to the length of the spadix (the spadix of Monstera oreophila is 0.73 times as long as the spathe whereas in Monstera gentry the spathe is less than 0.56 times as long). While both species have short pale lineations on the upper blade surface those of Monstera oreophila are less uniform and less prominent while those of Monstera gentryi are both more numerous and more uniform. Another species similar to Monstera gentryi is Monstera lentii which differs by having leaf blades bearing a single row of perforations, these usually beginning very near the midrib and extending more than 2/3 of the way to the margins as well as having primary lateral veins often 2.0–2.5 cm apart. In contrast the leaf blades for Monstera gentryi has two rows of perforations usually with a series of small perforations near midrib and with a second larger set usually beginning very near the midrib and extending more than 2/3 of the way to the margins as well as by having the primary lateral veins much closer together, especially near base.³
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Monstera gentryi Croat, M.Cedeño & O.Ortiz
2. Phytotaxa 514: 213 (2021) — protologue.