International Aroid Society

17. Syngonium auritum (L.) Schott, Wiener Z. Kunst 3:780. 1829.

Arum auritum L., Sp. PI. ed. 2, 1371. 1763. TYPE: Species No. 1079-17 in Linnaean Herbarium (LINN).
Caladium auritum Vent. ex Willd., Spec. PI., ed. 4, 4 (Part 1):491. 1805. TYPE: Jamaica- (not seen).
Syngonium plumieri Schott, Prodr. Syst. Aroid. 206, 1860. TYPE: Santo Domingo, Plumier (not seen).

Juvenile plants with stems scandent; blades ovate, acute at the apex, sagittate to hastate at the base. Adult stems hemiepiphytic, somewhat scandent, slightly
glaucous, 1.5-2 cm diam.; internodes 4-9 cm long, with one large feeding root and several clasping roots per node (fide Birdsey, 1955); petioles 15-48 cm long, broadly sheathed usually 4/5 their length (rarely to 2/3); blades usually trisect or sub-5-pedatisect, rarely 5 pedatisect, the lobes confluent, the median lobe 10-30 cm long, 6-20 cm wide, broadly elliptic, abruptly acuminate at the apex, the base obtuse, the tissue continuous with the lateral lobes, the first pair of lateral lobes ovate to elliptic, 6-21 cm long, 3-11 cm wide, acute at the apex, strongly inequilateral, usually conspicuously auriculate on the outer side at the base, the auricle sometimes free, then 4-10 cm long, to ca. 4 cm wide, the upper surface semiglossy, medium green, the lower surface paler; primary lateral veins mostly 5-7 pairs, joining the midrib at a 20-45° angle.
Inflorescences to 3 per axil; peduncle 7-13 cm long; spathe tube cylindroid, 4.2-8.5 cm long, 1-1.9 cm diam., dark green outside, green inside with a suffusion ofbronzy red at the base; spathe blade ovate in outline when opened, mucronate at the apex, conspicuously constricted at the base, 12-18 cm long, 7-10 cm wide (flattened), creamy white on both sides, sometimes greenish white on the outside and creamy white tinged faintly with violet purple within; spadix extending to 1/2 as high as the spathe blade; pistillate portion of the spadix 3.4-4.8 cm long, 9-12 mm diam., the flowers mostly rhombic to 5- or 6-sided, the stigma discoid, dark yellowish green (fide Birdsey, 1955); staminate portion of the spadix 3.5-9.2 cm long, rounded at the apex, slightly attenuate toward the apex, the sterile staminate section 7-17 mm long, creamy white, oblong, slightly attenuate at the apex, the sterile staminate flowers larger and more irregular than the fertile staminate flowers, the fertile staminate flowers 2-5 (usually 4), the synandrium retuse at the apex, the stamens fused together only on the inner side.
Infructescences pendent; fruiting spadix 7-7.8 cm long, 1.4-2 cm diam. Figs. 35, 36.

DISTRIBUTION: The species is known from Jamaica, Cuba and Hispaniola in the West Indies. It is the type species for the genus. The species can be recognized by its elongate spathe tube and the spathe blade which is up to twice as long as the staminate part of the spadix. An unnumbered Hitchcock collection at MO from Lucea, Jamaica, is anomalous in having the median lobe with a conspicuously sinuate margin. The species frequently has weakly irregular margins and the Hitchcock collection seems to be merely a gross exaggeration of this character.
According to Birdsey (1955) the species may flower all year but no particular individual is in flower continuously.

CUBA: Principes, near railroad, Shafer 421 (CM).
HAITI: DUNORD: Trail between Milot and Citadel, Fairchild s.n. (US); Port Margot to Cornell, Nash 185 (NY); Vicinity of Dondon, Leonard 8671 (US). NORDOUEST: Vicinity of Bassin Bleu, Leonard 14894 (US). He de la Gonave, vicinity Anse Galette, Leonard 3078 (US).
JAMAICA: HANOVER: Lucea, Hitchcock s.n. (MO). MANCHESTER: Bethany, Wolle s.n. (CM);
Mande Ville, Britton 1053 (NY). PORTLAND: Port Antonio, Hitchcock s.n. (MO); Stony River Base Camp, 1250ft, Morley & Whitefoord 686, 708 (MO). ST. ANDREW: Kingston, Hope Gardens, Skutch s.n. (F). ST. CATHERINE: Bog Walk, Hitchcock s.n. (MO). ST. THOMAS: Fountain Inn, 500 ft, Yuncker 17526 (F, MICH); House Hill, Maxon 9047 (NY, US). TRELANY: Windson, Miller 1455 (US).