Zygogynum ledermannii (Diels) Vink, 2016

Vink, W., 2016, The Winteraceae of the Old World. VIII. Some Zygogynum species from New Guinea, Blumea 61 (1), pp. 41-50 : 45-46

7. Zygogynum ledermannii (Diels) Vink , comb. nov. — Fig. 1 , 4

Zygogynum ledermannii (Diels) Vink. — Drimys ledermannii Diels (1916) 243. — Bubbia ledermannii (Diels) B.L.Burtt (1936) 3; A.C.Sm. (1943) 149. — Type: Ledermann 8990 (holo B).

Shrub 1–3 m high or treelet. Branchlets slender, (very) dark brown. Leaves scattered or in groups separated by long internodes; petiole 5 –12 mm long, shallowly grooved to flat above, rounded below; blade (narrowly) obovate to obovate-oblong, 7–15 by 2.5–5 cm, membranous to chartaceous, in sicco greenish to dark grey below; apex acute and up to 10 mm rounded broad-acuminate, base acute; midrib impressed above, prominent below; secondary nerves at 60–80° with midrib, arcingly joined at some distance from margin, prominulous on either side. On lower leaf surface only stomata white, solitary and/or in strings, pro specimen usually over (part of) secondary nerves or usually not so; oil cells scattered to not apparent. Inflorescences with c. 3 partial inflorescences, these 2 cm long, with rather thin axes, 3–7-flowered, flowers inserted on axes 1st (or 2nd) order; empty bracts below inflorescence 1; pedicels 2 –5 mm long, rather slender. Only buds, old flower, and young fruitlet seen. Calyx 3–4-lobed, 0.7–1 mm long, thin, rough by many oil cells. Petals (5–) 6 in 2 series, free or for up to 0.3 of their length abaxially connate. Stamens 12; thecae apically touching. Carpel solitary; stigma as long as carpel apex, sometimes very shortly but abruptly descending adaxially; ovules 30–32. Fruitlet probably a rather hard berry; when immature globose, green turning pink, 8 mm diam; base rounded, without stipe. Seeds not seen.

Distribution — PNG, Sepik area: Etappenberg and Hunstein Range.

Ecology — Undergrowth in hill forest at 450–850 m altitude. Flowering July, October; young fruit July.

Specimens examined. PAPUA NEW GUINEA, East Sepik Prov.,Etappenberg, Ledermann 8973 (B†), 8973a (K), 8990 (B), 850 m alt.; Hunstein Ra., Mt Samsai, Takeuchi 6212 (L), 450 m alt.

Notes — This species has thin, dark, pointed leaves and a solitary carpel.

The presence of stomata over the secondary nerves is variable. The connation of the petals is variable even within a flower and is of the same type as described for the species from New Caledonia ( Vink 1977: 229) .

The type material lacks flowers, only old carpels are preserved.

In the Winteraceae infestations of the leaves are rare, but in Z. ledermannii two collections show similar striplike damage, probably made by a mite.

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.).

Fig. 4 Zygogynum ledermannii (Diels) Vink.Flowerbud;calyx and one outer petal removed,showing three stamens.The removed petal was basally con- nate with the adjoining petals and left there scars on the abaxial sides of the thick margins (from Takeuchi 6212).