SYNGONIUM ADSETTIORUM

Species

PROTOLOGUE: Syngonium adsettiorum , published in Novon 27: 53 (2019).

Syngonium adsettiorum Croat, O. Ortiz & J. S. Harrison, sp. nov. It differs from Syngonium sparreorum Croat by having petioles sheathed to near the apex, leaf blades rounded and weakly short-apiculate at the medial lobe apex, narrowly rounded at the lateral lobe apices, and shorter inflorescences (spathe blade 5.5 cm long vs. 7.5–8.5 cm long for Syngonium sparreorum) and infructescences (to 5.5 cm long and 2.7 cm diam. vs. 13 cm long and 5 cm diam. for Syngonium sparreorum). Type: Panama. Panamá: Altos de Cerro Azul, El Torreón, Calle Kirkpatrick, a un costado de la casa de William Adsett, 09°12'40\"N, 79°24'54\"W, 16 Sep. 2015, O. Ortiz, A. De Sedas, P. Palma, Y. González, J. Harrison & L. Harrison 2517 (holotype, MO-2922382!; isotypes, FT!, PMA!).

DISTRIBUTION: Panama: Panama.

DISTRIBUTION NOTE: Panama: Panamá Province.

SPECIES DESCRIPTION:

Nomadic vine; appressed-climbing, growing to 4 m on trees; internodes longer than broad except near the apex, drying medium yellow-brown, conspicuously ridged longitudinally; sap milky. Leaves widely scattered on stem; petioles (8.5)18.5–20.0 cm long, sheathed to near the apex, free portion 1.0–1.5 cm long, the sheath rolled inward, margin moderately thick, persisting; petiolules 8–10 mm long; blades trisect, (15.0)21.2–22.5 cm long, (16.0)18.3–27.5 cm wide, moderately coriaceous, dark green and matte above, slightly paler and semiglossy below, drying dark brown, matte and sparsely short pale-lineate above; medial lobe elliptic, rounded and weakly short-apiculate at apex, obtuse at base, (11.5)18.5–19.5 cm long, 7.7–8.6 cm wide, slightly inequilateral (one side 8 mm wider); lateral lobes (8.0)11.1–12.7 cm long, (2.8)5.0–6.4 cm wide, narrowly rounded at apex, rounded to obtuse at base; midrib weakly and obtusely sunken, concolorous above, reddish, narrow rounded, drying several-ribbed, minutely granular and nearly concolorous below; primary lateral veins 3 per side, departing midrib at 20–30°, the lowermost weak and near the border, the 2nd pair prominent and extending to near the apex, the uppermost pair weak; tertiary veins moderately obscure.⁴

INFLORESCENCE:

Inflorescences 4 per axil; prophylls 12–14 cm long; peduncle 6–8 cm long, drying finely wavy-ribbed, yellowish brown; spathe 10–11 cm long; spathe tube 5 cm long, drying 1.8–2.5 cm diam., medium green with white margins on both surfaces, drying dark green; spathe blade medium yellow-brown, initially persistent, 5.5 cm long, 4–5 cm wide, 3.5 cm wide at anthesis, white inside, creamy white on outside, flattening to 5.5 cm wide; spadix 8.5 cm long; staminate portion 6.7 cm long, 1.2 cm diam.; sterile staminate portion 2.5 cm long, the lower thickened staminodia 3.0–3.2 mm long, 2.0–2.5 mm wide, these immediately transitioning to longer and thicker staminodia, 4.0–4.5 mm long, 1.5–2.5 mm wide, the next 4 rows irregularly shaped staminodia 2 mm long, 1 mm wide; pistillate spadix 1.5 cm long, 9 mm diam. at base, 6 mm diam. at apex. Infructescences pendent with spathe tube olive-green.⁴

ECOLOGY:

Syngonium adsettiorum is endemic to Panama, known only from the type locality in Panama in the Cerro Jefe Region at 783 m, in a Tropical wet forest life zone.⁴ altitude: 783 m

ETYMOLOGY:

The plural epithet adsettiorum honors the Adsett family: the type was collected beside the house of William Adsett at Altos de Cerro Azul in Panamá Province, Panama, in 2015. The Latinized ending means "of the Adsetts."⁴

NOTES:

1. The species is a member of sect. Syngonium and is characterized by trisect, dark brown drying leaves with moderately coriaceous, more or less elliptic slightly inequilateral leaflets which are rounded a apex and with distinct petiolules as well as a cluster of up to 4 inflorescences per axil with the tube medium green on both surface and somewhat persistent, medium brown-drying spathe blades. In the last revision of Syngonium⁵ the species keys to Syngonium sparreorum Croat from western slope of the Ecuadorian Andes at 250 m elevation. That species differs by having petioles sheathed only ½ to 2/3 their length, leaf blades abruptly acuminate at apex and larger inflorescences with peduncles 7–10 cm long and infructescences to 13 cm long.⁴