Zygogynum haplopus (B.L.Burtt) Vink, 2014

Vink, W., 2014, The Winteraceae of the Old World. VII. Zygogynum in the Solomon Islands (incl. Bougainville), Blumea 59 (2), pp. 155-162 : 159-161

Zygogynum haplopus (B.L.Burtt) Vink , comb. nov. — Fig. 1 , 2

Bubbia haplopus B.L. Burtt (1936) sub t. 3315.— Belliolum haplopus (B.L.Burtt) A.C.Sm.(1942) 438,(1943b) 153;F.S. Walker (1948) 184; Whitmore (1966) 126, 132; Corner (1969) 576.— Type: Waterhouse 90 (= b.743) (holo K; F).

Belliolum burttianum A.C.Sm. (1942) 439, (1943b) 153, 154 f. 5. — Type: Kajewski 1680 (holo A; iso BISH).

Belliolum gracile A.C.Sm. (1942) 439, (1943b) 153. — Type: Brass 2898 (holo A; iso B, BISH).

Belliolum kajewskii A.C.Sm.(1942) 440,(1943b) 153.— Type: Kajewski 2099 (holo A; iso BISH, BO).

Shrub or tree(let) 3–18 m high and up to 20 cm d.b.h.; bark grey green to dark brown, smooth to fissured; wood white, cream- or pale (or dark) brown. Branchlets rather slender, (dark grey-) brown. Leaves scattered to dense at the end of branchlets; petiole 5–25(–33) mm long, shallowly grooved above, rounded below, dark brown to blackish; blade elliptic to (narrowly) obovate to oblanceolate, 4–26.5 × 2 –10 cm, chartaceous, in sicco light brownish grey to brown below; apex obtuse to rounded, base (narrowly) acute (to shortly attenuate); midrib impressed above, prominent below; secondary nerves at 60–80° with midrib, arcingly joined at some distance from the margin, distinct above, distinct to prominulous below. On lower leaf surface stomata white, solitary and/or in short strings or small clusters, also present over secondary nerves but often less dense there (or absent over thickest nerves); oil cells not apparent to dense and dark coloured. Inflorescences with 3–8 partial inflorescences, these 1.5–7.5 cm long, with rather slender axes but not pendulous, 1- or 1–3-flowered; empty bracts below inflorescence 0–4(–6); pedicels of solitary flowers 4–72 mm long, rather slender, in triads 4–40 mm long, slender, under fruit solid. Flowers scented. Calyx cup-shaped, 1–1.5 mm long, thin, smooth, margin with 2–3 small tips and sometimes somewhat ruptured. Petals 7–22, outer ones elliptic to obovate, inner ones narrowly so, white, outer ones 5.5–13 × (1.5–)2.2– 6 mm, inner ones 4–10 × (0.8–) 1–5 mm, (broadly) rounded, inner petals adaxially smooth, with longitudinal ribs, and/or apically with thickenings. Stamens 8–36, 2–3.5 mm long, except for thecae usually finely papillate, thecae lateral, sterile apex elliptic or ovate and rounded to (narrow-)triangular and acutish, 20–60 % of length of stamen; pollen in tetrads. Carpels solitary or 1–8, free, 2–3 × 1.5–2 × 0.8–1.3 mm; stigma as long as the carpel apex or slightly longer at one or both ends, not descending adaxially; ovules 13–38. Fruitlets a rather hard berry, pink to red; ellipsoid to obovoid-globose, up to 15(–25) mm diam, stipe absent or rather slender and up to 2(–5) mm long, stigma apical, 3–6 mm long. Pericarp 2–7 mm thick, with nests of brachysclereids, said to taste hot peppery; pulpa almost not developed. Seeds 5–36, light greyish brown (black when immature), narrowly obovoid, on faces towards each other flat and smooth, convex free surface with very fine ribs and pustules, up to 6 × 4 × 3.5 mm.

Distribution — Solomon Islands, from Bougainville I. to San Christoval I. (no collections seen from Malaita).

Habitat & Ecology — Primary or disturbed lowland, hillside, or ridgetop forest, at 0–1900 m altitude (the single collection above 1700 m is Kajewski 2630, see Folklore). Flowering and fruiting throughout the year, but ripe fruits mostly in August.

Vernacular names — Kwara’ae language: Aisigwarigwari (sometimes erroneously Aibosbos, the name of Psychotria ssp.); other names: Mahuisihuisi, Mamamoto, Ororojenari, Ororfoyu, Paru, Ses-a-vere.

Folklore — Kajewski (2630) reports from Tutuve Mountain on Guadalcanal Island that at 1900 m this tree (‘leas-a-vera’) is planted in taro gardens to make the taro grow well (flourish).

Etymology of the generic name Bubbia . Philippe-Dominique van Tieghem died from yellow fever on 6 January 1839, during a business visit to Marti- nique. Three months later, on 19 April,at Bailleul in France, his wife Amélie Bubbe gave birth to a son who was named Philippe Édouard Léon. Soon after, Amélie also succumbed. The orphan was first taken care of by his aunt and uncle Stéphanie and Napoléon Bubbe, both unmarried, and later on by his sisters ( Costantin 1914). As a scientist, he became known by his first name. Philippe van Tieghem apparently honoured his mother and her family by naming a new genus in the Winteraceae as Bubbia .

More recently two alkaloids obtained from Zygogynum pauciflorum from New Caledonia were named bubbialine and bubbialidine ( Ahond et al. 1990).The latter is also found in Phyllanthus amarus (Euph.) ( Nahar et al. 2011: 122) .

Figures

Fig. 1 Zygogynum haplopus (B.L.Burtt) Vink. a. Three generations of inflorescence at the top of a twig: scars (T1), old flowers and buds, resp.; Lf = leaf; b. open flower with erect inner petals: b1. small inner petal; b2. inner petal with adaxial apical thickenings; b3. very small petal with one theca; c. all petals from a just opening flower, adaxially: c1. outer petals; c2. inner petals; d. inner petals with extreme forms of adaxial thickenings, the smallest petal seen from both lateral sides; e. opened bud: two inner petals with adaxial apical thickenings overtop stamens and carpels (a: Brass 3063; b. NGF 45743; c: BSIP 4279; d: Brass 2959; e: Kajewski 1680). — Scale bars = 2 mm.

Fig. 2 Zygogynum haplopus (B.L.Burtt) Vink. a. Two mature slender stamens: a1. lateral; a2. abaxial, sublateral, and adaxial view, resp.; b. three mature broad stamens; lowest (left) middle and highest from the same flower; c. the stamen replacing a carpel is larger than the neighbouring stamens – from a bud; d. carpels, slender; e. carpels, broad; f. carpel from bud, longitudinal section – some ovules already pressed out of line; g. ripe fruit, opened, showing seeds (a, d. Brass 2959; b, e. Craven & Schodde 307; c. RSS 1192; f. Corner RSS 41; g. BSIP 6418). — Scale bars: a–e = 2 mm; f = 0.05 mm; g = 4 mm.