Gossia conduplicata N. Snow, 2020

Snow, Neil, 2020, A revision of New Caledonian Gossia N. Snow & Guymer (Myrtaceae), Adansonia 42 (7), pp. 131-177 : 152

Gossia conduplicata N. Snow , sp. nov. ( Figs 6 ; 12E-G )

Resembling Gossia diversifolia except that much to most of the blade

itself is conduplicate, and it lacks the winged branchlets of G. diversifolia . TYPUS. — New Caledonia. Grande Terre, North Prov ., Poindimié , 165°19’59.988’’E, 20°56’36.996’’S, 4.VIII.1967, MacKee 17222 (holo-, P [missing] ; iso-, P[P00781068], BISH[fragment], NOU[- NOU029074], WELTU).

REPRESENTATIVE HERBARIUM SPECIMEN. — P00781068. ETYMOLOGY. — In reference to the partially to strongly folded

(conduplicate) leaf blades.

DISTRIBUTION, HABITAT AND PHENOLOGY. — Known only from the type collection at or near Poindimié ( Fig. 6 ) in humid forests at 50 meters. Flowering unknown; fruiting in April.

DESCRIPTION

Shrubs

To 3 m.

Branchlets

Terete; internodes> 5 mm.

Leaves

Coriaceous, 2 per node; petioles 1.5-2.5 mm, flattened to broadly sulcate above; blades 2.0-3.0 × 1.2-2.0 cm, ovate, base rounded but conspicuously conduplicate above petiole (up to or more than half the length), surface moderately to strongly undulate, apex acute, midnerve above flush to slightly sulcate, secondary veins not raised above, oil glands absent from lower surface.

Inflorescence

A monad or simple cyme, axillary and terminal, sometimes nodding apically; extrafloral bracts absent.

Bracteoles c. 1 mm, narrowly elliptic, glabrous.

Hypanthium c. 3 × 3 mm, campanulate, surface smooth, glabrous.

Calyx

Lobes 4(-5), 1.2-2.2 mm, broadly rounded, glabrous above and below, green.

Petals Unknown.

Filaments Not seen, estimate of c. 80.

Style

Not seen; ovary apex sparsely hairy.

Fruit

4.5-5.5 × 4.5-5.5 mm, globular, base rounded, green (immature) to red (mature); seed 1.

REMARKS

This poorly known species is diagnosed by its strongly conduplicate leaves with undulate margins, and efforts to relocate it should be a high priority. The calyx lobes in fruit are reflexed in the one known specimen, unlike the more common condition of ascending to erect lobes. The similar species G. diversifolia has winged branchlets. Gossia conduplicata sp. nov. differs from G. bourailensis sp. nov. by its more undulate leaf margin and narrowly acute leaf apex. The base of the leaf blade in Gossia katepahiensis can be conduplicate, but only slightly so. The type specimen of Gossia diversifolia was collected from Balade, farther north along the eastern coast from Poindimié, the one known locality of G. conduplicata sp. nov. Further study is needed to better understand the differences of these two taxa.

Figures

FIG. 6. — Distribution maps for Gossia bourailensis N. Snow, sp. nov., G. colnettiana (Guillaumin) N. Snow, G. conduplicata N. Snow, sp. nov. and G. diversifolia (Brongn. & Gris) N. Snow.

FIG. 12. — A-D, Gossia colnettiana (Guillaumin) N. Snow: A, branch and inflorescence; B, bracteoles and flower bud; C, flower minus petals and stamens; D, longitudinal section through flower showing bilocular ovary with axile placentation;E-G, Gossia conduplicata N.Snow,sp.nov.: E, branch with inflorescences;F, leaves (lateral (left) and dorsal (right) views);G, immature fruit views, apical (left) and lateral (right); H-K, Gossia conspicua (Vieill. ex Guillaumin) N. Snow, comb.nov.: H, branch with dense leaves and short internodes; I, strongly recurved leaf blades; J, flower (apical view minus two petals at left), lateral view (right); K, immature fruit. Vouchers: A-C, MacKee 19108 (BISH);D, Jaffré 3228 (NOU);E-G, MacKee 17222 (NOU); H, I, K, Veillon 5958 (NOU); J, MacKee 5328 (P). Scale bars:A, E, 2 cm;B-D,G, J, K, 2 mm; F, 1 cm; H, I, 5 mm.