SYNGONIUM TACOTALPENSE
PROTOLOGUE: Syngonium tacotalpense , published in Novon 27: 63 (2019).
Syngonium tacotalpense Díaz-Jiménez & Croat, sp. nov. It differs from Syngonium angustatum Schott in having glaucous stems that are not muricate, leaf blades with more pairs of primary lateral veins (four to eight vs. three to five), and eight (to 10) inflorescences per axil. Type: Mexico. Tabasco: Mpio. Tacotalpa, Buenos Aires, Selva alta perennifolia, 17°21'N, 92°42'W, 14 May 2005, P. Díaz Jiménez & J. M. Ascencio Rivera 165 (holotype, MO [2 sheets] MO-6355420!, MO-6355671!; isotypes, K!, UJAT!, US!).
DISTRIBUTION: Mexico (Tabasco): Mexico Southeast, Tabasco.
DISTRIBUTION NOTE: Mexico: Tabasco.²
SPECIES DESCRIPTION:
Nomadic vine; Leaves with petioles 20–59 cm, sheathed 2/3–3/4 their length; blades trisect or 5- to 11-pedatisect, thin, upper surface dark green, lower surface paler; segments 5, usually free; posterior segments rarely auriculate at base; median segment oblong-elliptic to lanceolate, abruptly acuminate at apex, decurrent at base, 29–38 cm long, 6.2–7.3 cm wide; rachis usually cruciform; midrib deeply sunken and concolorous above, prominently rounded below; primary lateral veins 4–8 per side on median segment; collective veins 2.³
INFLORESCENCE:
Inflorescences ca. 8 (to 10) per axil; prophylls ca. 13.5 cm; peduncle dark olive-green, 6.5–7.5 cm, erect at anthesis, 13 cm and pendent in fruit; spathe 9.3 cm long; spathe blade 7.2 cm long, 4.5 cm wide at anthesis, cream; tube of spathe ovoid to ellipsoid, ca. 3.6 cm, green yellowish inside and green outside; spadix with pistillate portion ca. 2.2 cm, 10 mm diam., greenish cream and yellowish; staminate portion ca. 5 cm, 12 mm diam., cream. Infructescences pendent, peduncles green, weakly flattened, ca. 13 cm; fruits ovoid, 3.5–5.0 cm long, 1.5–3.0 cm diam., reddish; spathe persistent in fruit. The type specimen had fruits in May.³
ECOLOGY:
Syngonium tacotalpense is endemic to Mexico, known only from the type locality at 450 m in a Tropical moist forest life zone.³ altitude: 450 m
ETYMOLOGY:
Named for the municipality of Tacotalpa in Tabasco, Mexico, where the type was collected, as the original description states. The Latinized ending-ense means "from that place."²
NOTES:
1. Syngonium tacotalpense is a member of section Syngonium and is characterized by its hemiepiphytic habit, with leaf blades of adult plants trisect or 5- to 11-pedatisect and leaf blades of the pre-adult climbing phase simple, usually hastate or sagittate. The species is perhaps most easily confused with Syngonium angustatum, which differs in having stems not glaucous, usually sparsely muricate, and fewer primary lateral veins (three to five vs. four to eight) and inflorescences ca. seven versus ca. eight (to 10) per axil.³
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Syngonium tacotalpense
2. Novon 27: 63 (2019) — protologue.