Gossia angustifolia N. Snow, 2020

Snow, Neil, 2020, A revision of New Caledonian Gossia N. Snow & Guymer (Myrtaceae), Adansonia 42 (7), pp. 131-177 : 138-139

Gossia angustifolia N. Snow , sp. nov.

( Figs 3 ; 4A-C )

Leaves narrowly elliptic, cuneate at base, the margin slightly sinuous, about three times longer than broad, abaxial surface glands dense, placentation basal.

TYPUS. — New Caledonia. Grande Terre , North Prov. Entre Tao et Ouaième: Vallée Pouai, 20°35’33.00”S, 164°49’12.00”E, 11.IX.1961, MacKee 15612 (holo-, NOU [ NOU053037 ]; iso-, BISH [leaf fragment], MO[ MO-5906585 ]).

PARATYPI. — New Caledonia. Grande Terre , Haute Diahot , Paala, 600 m, 15.VII.1977, MacKee 33461 ( BISH [fragment], NOU [ NOU053245 ]) ; Col d’Amos, 20°17’60”S, 164°25’42”E, 13.X.2002, Munzinger 1489 et al. (MO[ MO-5841144 ], NOU [ NOU002733 ], P[P00354502]) ; Col d’Amoss, 20°18’22”S, 164°23’48”E, 14.X.2002, Tronchet 387 (K n.v., MO[ MO-5906585 ], NOU [ NOU003170 ], P[P00354930]) ; Vallée de Néouna (Goapin), entre Aoupinié NW et Forêt plate, 165°13’35.1”S, 21°8’38.3”E, 31.VII.2012, Vandrot 597 & Chambrey (MO, n.v., MPU[ MPU028535 ], P[P02089718]).

ETYMOLOGY. — In reference to the relatively narrow leaves, compared to most congenerics in New Caledonia.

REPRESENTATIVE HERBARIUM SPECIMEN. — P00354930.

DISTRIBUTION, HABITAT AND PHENOLOGY. — Gossia angustifolia sp. nov. occurs on the edge of the Massif du Panié and at Col d’Amoss ( Fig. 3 ), sometimes common locally; in gallery forests over micaschistes, c. 100-600 m altitude. Flowering November (material scant); fruiting July through October.

DESCRIPTION

Shrubs or trees

3-8 m, sometimes densely branched.

Bark

Brownish and somewhat rough.

Branchlets

Terete to laterally compressed; internodes> 5 mm., emerging reddish.

Leaves

Coriaceous, 2 per node; petioles 1.2-3.5 mm, terete; blades 5.0-9.0 × 1.9-3.3 cm, narrowly elliptic, base cuneate, surface flat, margin flat to slightly wavy, apex acute, midnerve above sulcate, secondary veins slightly raised above, oil glands of lower surface dense but faint. Inflorescence 2-2.5 cm, of few-flowered racemes or panicles, terminal and axillary; pedicels 0.3-1.4 cm; extrafloral bracts lacking or scale-like.

Bracteoles

1.5-2 mm, narrowly oblanceolate, sparsely sericeous.

Hypanthium

2.5-3.5 mm, campanulate or urceolate, width in flower unknown, surface smooth, sparsely sericeous; ovary apex glabrous.

Calyx

Lobes 5, 1.2-1.5 mm, broadly rounded, glabrous above, sparsely sericeous below, greenish.

Petals stamens and style

Unknown.

Berry

6-8 × c. 7 mm, globular, base rounded, whitish to reddish; seeds 2.

REMARKS

Gossia angustifolia sp. nov. is recognized by its narrowly elliptic leaves with slightly undulate (in sicco) margins and (usually) dense but small oil glands on the lower surface. It can resemble G. ramiflora sp. nov. based on the slightly undulate leaf margins and their overall shape, but the margins of G. ramiflora sp. nov. typically are significantly more undulate. It also can resemble G. vieillardii , but that species has fewer oil glands on the lower leaf surface. Preliminary results suggest this species is atypical in the genus by virtue of its basal placentation in a single locule ( Fig. 4C ). The laminar oil glands are less dense on one specimen (Vandrot 597).

Figures

FIG. 3. — Distribution maps of Gossia alaternoides (Brongn. & Gris) N. Snow and G. angustifolia N. Snow, sp. nov. Note: in all distribution maps, gray areas indicate ultramafic substrates,slash-hatching indicates dense humid forests, and dotted areas indicate protected areas;icons with “T” indicate type localities.

FIG. 4. — A-C, Gossia angustifolia N. Snow, sp. nov.: A, branch; B, inflorescence in part; C, flower with petals and stamens removed, and in longitudinal section at left; D-G, Gossia aphthosa (Vieill. ex Brongn. & Gris) N. Snow subsp. aphthosa: D, branch showing leaves with corky swellings at base of leaf and ramiflorous inflorescences; E, detail of corky swellings; F, detail of flower with reflexed petals; G, remnants of inflorescence in axil (with corky swellings) of dehisced leaf; H-J, Gossia bourailensis N. Snow, sp. nov.: H, branch with inflorescences; I, detail of flower bud; J, detail of flower with petals removed showing calyx lobes, staminal ring, hairy ovary apex, and style with proximal pubescence. Vouchers: A-C, MacKee 33461 (NOU); D, F, MacKee 28444 (P); E-G, MacKee 26722 (NOU); H-J, Balansa 1516a (P); K, Veillon 5958 (NOU); J, MacKee 5328 (P). Scale bars: A, D, E, G, H, 2 cm; B, 5 mm; C, F, I, J, 3 mm.