SYNGONIUM PURPUREOSPATHUM
PROTOLOGUE: Syngonium purpureospathum , published in Novon 27: 62 (2019).
Syngonium purpureospathum Croat & Raz, sp. nov. It differs from Syngonium auritum (L.) Schott in having a violet-purple spathe and 3-lobed leaf blades that lack auricles on the lateral lobes. Type: Caribbean. Jamaica: St. James Parish: Johnson Distr., Cockpit Country, 1 mi. S of Sweet Water, White Rock Hill, ca. 100 m N of main rd., 18°26'N, 77°50'W, 640 m, 14 Aug. 2007, L. Raz, K. Wendelberger, H. Jacobsen, C. Jones, G. Proctor & S. Palmer 718 (holotype, IJ!; isotypes, FTG!, MO-5996108!, UCWI!).
DISTRIBUTION: Jamaica: Jamaica.
DISTRIBUTION NOTE: Jamaica: Saint James.
SPECIES DESCRIPTION:
Growing on east facing ledges and cliffs, on lower parts in shade; epiphytic to epipetric; internodes short, to ca. 1 cm diam., thicker than broad toward apex, drying closely and sharply ribbed, yellow-brown, the uppermost nodes minutely and irregularly ridged. Leaves with petioles 14–24 cm long, sheathed to within 1.5–3.5 cm from base of blade; sheath spreading, 1.8–2.0 cm wide midway, free-ending at apex, weakly undulate along the margins, the free portion subterete, drying closely and minute acute-ridged; blades trisect; medial segment ovate, 14.3–20.3 cm long, 6.9–11.7 cm wide, 1.6–2.1 times longer than wide, slightly inequilateral, one side 6–10 mm wider, acute to narrowly rounded and short-apiculate at apex, rounded to rounded-truncate at base, scarcely to not at all confluent onto lateral segments; lateral segments much smaller, directed at 115–155° angle from midrib, oblong to oblong-elliptic, slightly inequilateral, one side 2–8 mm wider, rounded at apex, the inner margin acute and weakly confluent onto medial lobes (confluent portion 1–2 mm wide), the outer margin acute to weakly auriculate (but not forming a lobe), 7.4–12.5 × 2.5–4.5 cm; primary lateral veins 6 or 7 per side.³
INFLORESCENCE:
Inflorescences one per axil, up to 3 borne in uppermost leaf axils; prophylls 9.0–13.2 cm long, 2-ribbed; peduncle 4.0–6.5 cm long, drying dark brown, 3–6 mm wide; spathe stiffly erect, 13.0–14.5 cm long, 6 cm wide when flattened, the tube oblong-elliptic, medium green, 4 cm long, drying 1 cm wide, dark brown, finely ridged and weakly pustular, the blade naviculiforme at anthesis with the lateral margins curled backward, violet-purple and semiglossy adaxially, green abaxially, drying medium yellow-brown on both surfaces; spadix to 10 cm long, the staminate portion extending about 2/3 up the length of the spathe; staminate spadix 6.5–7.0 cm long, drying 9 mm diam., pale green pre-anthesis, turning yellow at anthesis, drying dark brown, 7–9 wide, shedding copious yellow pollen; sterile staminate portion 1 cm long, 3 mm diam., slightly broadened at apex with a few staminodia, these 0.6–2.0 mm long, 0.9–1.2 mm wide, the pistillate portion 3.3 cm long, 4–5 mm wide; pistils widely scattered, 3–4 across the width of the spadix; style rounded, drying blackened, 2 mm diam.; Fruits not seen. Flowering seen in August.³
ECOLOGY:
Syngonium purpureospathum is endemic to Jamaica, known principally from the Cockpit country of St. James Parish in Johnson District on craggy limestone cliffs in Jamaican moist forest at 640 m elevation.³ altitude: 640 m
ETYMOLOGY:
From Latin purpureus, "purple," and spatha, "spathe," the derivation the original description gives, referring to the purple spathe that distinguishes this Jamaican species.²
NOTES:
1. The species is a member of section Syngonium and is characterized by its non-glaucous stems which are usually densely covered with brownish projections, petioles sheathed 1/2–4/5 or more of their length and obtusely 1-ribbed adaxially, the trisect to almost 5-lobed, yellowish green-drying leaf blades with the lateral leaflets usually conspicuously auriculate and usually nearly pinched-off, as well as having usually 6–8 inflorescences per axil, a non-glaucous peduncle and a spathe that has the tube green on both surfaces. Syngonium purpureospathum is most closely related to Syngonium auritum, a species which also occurs in Jamaica. It differs from Syngonium auritum in having a violet-purple spathe and 3-lobed blades which lack auricles on the lateral lobes of the leaf blades. In contrast Syngonium auritum has prominent auricles on the lateral lobes and a creamy white spathe, more typical of other species in the genus.³
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Syngonium purpureospathum
2. Novon 27: 62 (2019) — protologue.