Zygogynum oligocarpum (Schltr.) Vink, 1985

Vink, W., 2016, The Winteraceae of the Old World. VIII. Some Zygogynum species from New Guinea, Blumea 61 (1), pp. 41-50 : 48

11. Zygogynum oligocarpum (Schltr.) Vink — Fig. 1

Zygogynum oligocarpum (Schltr) Vink (1985) 53. — Drimys oligocarpa Schltr. (1913) 71, f. 1. — Bubbia oligocarpa (Schltr.) B.L.Burtt (1936) 3. — Type: Schlechter 16470 (holo B; iso P).

Shrub or tree up to 15 m high. Branchlets rather slender, brown. Leaves scattered; petiole 8–20 mm long, (almost) flat above, rounded below, brown; blade obovate, 14–27 by 5.5–9 cm, chartaceous; apex acute to obtuse and ultimately rounded, base acute; midrib impressed above, prominent below; secondary nerves at 60–70° with midrib, arcingly joined at some distance from margin, prominulous on either side. On lower leaf surface stomata covered with alveolar material, dense, solitary and in small clusters, also over secondary nerves; oil cells not apparent. Inflorescences with 3–5 partial inflorescences, these with thin axes, c. 9-flowered; flowers inserted on axes 1st to 2nd order; empty bracts below inflorescence 1–7; pedicel 7–10 mm long, slender. Calyx 2- or irregularly lobed, 1 mm long, thin, smooth. Petals 5–7, free, elliptic, yellowish or greenish white, outer ones 5 by 3 mm, inner ones 3 by 2 mm, apex broadly rounded. Stamens 9–18, c. 1.6 mm long, thecae apically touching; carpels 1–2, free, 2–2.5 by 1–1.5 by 1 mm; stigma as long as carpel apex, not or shortly descending adaxially. Fruitlets unknown.

Distribution — PNG, East Sepik Prov.

Specimens examined. PAPUA NEW GUINEA, East Sepik Prov.,Minjem Valley,

Wobbe, Schlechter 16470 (B, P), 400 m alt.

Notes — The above description deviates somewhat from that by Schlechter as the second specimen he used ( Moszkowski 281) is no longer available. In the type material the wax on the stomata has deteriorated, so the original colour of the lower leaf side is unknown.

I observed 9 and 10 stamens; judging by the floral remnants of Schlechter’s analysis the number of 18 in the original description is correct.

Zygogynum oligocarpum differs from Z. montanum by the distinctly longer stigma.

Figures

Fig. 1 Carpels, all with ventral side to the left, and at the same magnification. – a. Zygogynum archboldianum; b. Z. bosavicum; c. Z. clemensiae; d. Z. cruminatum; e. Z. cyclopensis; f. Z. ledermannii; g, g'. Z. longifolium; j. Z. megacarpum; h. Z. montanum; i. Z. oligocarpum; k, k'. Z. polyneurum; l. Z. schramii; m. Z. sororium; n. Z. staufferianum; o. Z. umbellatum (a. Brass 12712; b. LAE 58822; c. Clemens 4596; d. LAE 69143; e. Royen & Sleumer 6396; f. Takeuchi 6212; g. Vink BW 8413; g'. Robbins 2004; j. Burley & Ismail 4618; h. LAE 61131; i. Schlechter 16470; k, k'. Jacobs 9489; l. Vink BW 8458; m. Ledermann 11898; n. Balgooy 968; o. Boden Kloss s.n.).