SYNGONIUM CHURCHILLII
PROTOLOGUE: Syngonium churchillii , published in Novon 27: 56 (2019).
Syngonium churchillii Croat & O. Ortiz, sp. nov. It differs from Syngonium mauroanum Birdsey ex G. S. Bunting by having the lower outer margin of the lateral leaf blade lobes prominently narrowed (nearly pinched off) (vs. subtriangular or rounded). Type: Panama. Chiriquí: along Pan American Hwy., E of turnoff to Gualaca, 08°30'N, 82°17'W, 100 m, 17 Sep. 1984, H. W. Churchill 6033 (holotype, MO [3 sheets] MO-3202025!, MO-3202026!, MO-3285926!).
DISTRIBUTION: Panama: Panama.
DISTRIBUTION NOTE: Panama: Chiriquí Province.²
SPECIES DESCRIPTION:
Nomadic vine; stem scandent, climbing; internodes (0.5)1.0–2.0 cm, less than 1 cm diam., usually longer than broad, drying acutely several-ribbed, epidermis drying yellowish brown. Leaves with petioles 22–27 cm, sub-flattened adaxially with raised margins and medial rib, drying finely ribbed, sheathed to 14.3 cm, 0.62 its length, sheath acute at apex, margin persisting intact; blades 3-parted, 20–25 cm long, 20.5–23.5 cm wide, about as broad as long, subcoriaceous, dark green above, slightly paler below, drying medium brown, matte above, yellowish green and weakly glossy below; all lobes narrowly long-acuminate at apex; medial lobe 15.5–19.3 cm long, 3.6–7.8 cm wide, moderately inequilateral, one side 1.1–1.7 cm wider, attenuated at base; lateral lobes 14.5–15.0 cm long, 3.3–5.5 cm wide, markedly inequilateral, (one side 1.2–2.1 cm wider), narrowly acute at apex, markedly auriculate on outer margin at base, inner margin gradually attenuated; auricles narrow and elongated, directed parallel to petiole, 3.5–7.0 cm long, 1.0–2.5 cm wide, sometimes elliptic; sinus sub-quadrangular to parabolic, more or less truncate at apex, 3–5 cm deep, 2.0–2.5 cm wide midway; midrib weakly raised and concolorous above, drying darker, 5-ribbed below; primary lateral veins 6 to 10 per side, departing midrib at 50°–55°; primary collective vein 3–6 mm from margin; tertiary veins moderately inconspicuous below.³
INFLORESCENCE:
Inflorescences 2 or 3 per axil, pendent post-anthesis; peduncle 9.0–9.5 cm, 3–5 mm diam., drying blackened; spathe blade absent, tube 5–6 cm; 2.3–3.2 cm diam., green outside, maroon inside, drying dark blackened, matte; spadix with sterile staminate portion ca. 1.5 cm, mostly eaten away. Infructescence to 6 cm, 2.5 cm diam.; seeds 1.5–2.0 mm, 1.6–1.5 mm diam. Fruits are known in September.³
ECOLOGY:
Syngonium churchillii is endemic to Panama, known only from the type locality, at 100 m elevation in a Premontane wet forest life zone.³ altitude: 100 m
ETYMOLOGY:
Named in honor of the late Dr. Hugh Churchill, who made the only known collection of the species. Churchill collected for the Missouri Botanical Garden's Flora of Panama Project and found many new species, especially around the Fortuna Dam, then being developed. The Latinized epithet churchillii means "of Churchill."²
NOTES:
1. The species is a member of sect. Syngonium and is characterized by its sub-flattened petioles with raised margins and medial rib, sheathed to about 2/3rd its length with the sheath acute at apex and with an intact margin, 3-parted leaf blades drying medium brown, matte above, yellowish green and weakly glossy below with narrowly long-acuminate lobes, the medial lobe moderately inequilateral, lateral lobes markedly inequilateral, markedly hastate on outer margin at base, inner margin gradually attenuated, the auricles narrow and elongated, directed parallel to petiole, 6 to 10 primary lateral veins per side, 2 or 3 inflorescences per axil with the spathe tube green outside and maroon inside. Syngonium churchillii differs from Syngonium mauroanum by having the lower outer margin of the lateral leaf blade lobes prominently narrowed (nearly pinched off) (vs. subtriangular or rounded). Syngonium mauroanum and Syngonium neglectum are both seemingly easily confused with Syngonium churchillii. The former differs by having the lower outer margin of the lateral lobes subtriangular or rounded, not prominently narrowed. Syngonium neglectum, while sometimes having small leaves that are similar to those of Syngonium churchillii, differs by being restricted to Mexico and by having much larger inflorescences with the spathe blade alone 9–15 cm long and persisting intact and reflexed after anthesis. In contrast, the spathe of Syngonium churchillii is at most 6 cm long and deciduous, not persisting after anthesis.³
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Syngonium churchillii
2. Novon 27: 56 (2019) — protologue.