Gossia ramiflora N. Snow, 2020

Snow, Neil, 2020, A revision of New Caledonian Gossia N. Snow & Guymer (Myrtaceae), Adansonia 42 (7), pp. 131-177 : 168-169

Gossia ramiflora N. Snow , sp. nov. ( Figs 20 ; 21E-I )

Diagnosed by others in the genus by the prominently undulating leaf margins and (mostly) ramiflorous inflorescences.

TYPUS. — New Caledonia. Grande Terre , South Prov. , Farino: Forêt Mépéou, [21°37’5.016”S, 165°46’35.004”E], 500 m, 22.II.1966, MacKee 14417 (holo-, P [ P00462973 ]; iso-, CANB, K n.v., L n.v., MO[MO2907912], NOU [ NOU029712 ], P[P00462974], WELTU).

PARATYPI. — New Caledonia. Grande Terre , North Prov., Route Tiwaka Kono, 150 m, 30.I.1987, Jaffré 2844 ( NOU [ NOU029710 ], P[P00462983]) ; Western slope of Plateau de Dogny, 600-900 m, 10.XI.1958, MacKee 6537 (P[P00462984]) ; Along trail from Sarraméa toward Plateau de Dogny , c. 450 m, 1.IX.1982, McPherson 4924 ( BISH [fragment], BRI, MO[ MO-3211402 ], NOU [- NOU029702 ], P[P00462975]. — South Prov., Col d’Amieu, 500-600 m, 13.VII.1965, Bernardi 9611 ( NOU [ NOU029711 ], P[P00462982]) ; Col d’Amieu , Vallé de Toili, 350-400 m, 19.I.1965, MacKee 12002 ( NOU [ NOU029705 ], WELTU) ; Farino , Forêt du Pic Noir, 250 m, 21.I.1965, MacKee 12034 ( WELTU) ; Col d’Amieu , 350 m, 17.III.1965, MacKee 12272 ( BISH, CANB, K[K001000422], MO, NOU [ NOU029716 ], P[P00462985, P02088629], WELTU) ; Col d’Amieu , Route du Col Toma, 400 m, 31.III.1965, MacKee 12342 ( BISH, CAN- B[ CANB00593372 ], K[K001000420], P[P00462986], WEL- TU) ; Mont Nakada pente Sud, 600 m, XI.1979, MacKee 37618 (MO[ MO-6751048 ], NOU [ NOU029714 ], P[P02089879]) ; N.C. Mont Yora ( Pente Sud ), 700 m, 4.XII.1980, MacKee 38405 ( NOU [ NOU029560 ], MO[ MO-6751050 ], P[P02089962, P02089963, P05094544]) ; Mont Rembai , 700 m, 31. V.1990, MacKee 44919 ( NOU [ NOU029706 ]) ; Col d’Amieu , versant Canala, 350 m, 9.XII.1992, MacKee 46043 ( NOU [ NOU029557 ], P[P02089842]) ; Forested slopes near Mt Rembai, south of Col d’Amieu, c. 500 m, 7.XI.1982, McPherson 5089 ( BRI, MO[- MO-3218924 ], NOU [ NOU029704 ], P[P00462976]) ; Mt Rembai region , above Col d’Amieu, c. 575 m, 7. VI.1983, McPherson 5734 (MO[ MO-3211387 ], NOU [ NOU029703 ], P[P00462977], PTNB, WELTU) ; Mt Rembai , N of Col d’Amieu, in the forest reserve SW of Canala-La Foa Rd, 650 m, 26.VII.1978, Phillips & Schmid 3205 ( NOU [ NOU 53251], P[P00462978]) ; Col d’Amieu , Forêt de Rembai, 500 m, 12.XI.1980, Suprin 876 ( NOU [ NOU029709 ]) ; Région de Pouembout , au n. de “Forêt-Plate”, 26.III.1981, Suprin 1087 ( BISH fragment, NOU [ NOU029708 ]) ; Col d’Amieu , horaire de la Foa, c. 350 m, V.1973, Veillon 2894 ( NOU [ NOU029713 ], P[P00462979, P00462980, P00462981]; Col d’Amieu, Forêt Persan, vers 400 m, 15.IV.1993, Veillon 7654 ( NOU [ NOU029707 ]).

REPRESENTATIVE HERBARIUM SPECIMEN. — P00462973.

ETYMOLOGY. — From the Latin ramus (branch) and flos (flower), in reference to the flowers mostly arising from naked branches (before new leaves appear on young branches or proximal along branches to existing leaves).

DISTRIBUTION, HABITAT AND PHENOLOGY. — Central Grande Terre, especially in the area of Col d’Amieu ( Fig. 20 ); in humid forests over ultramafics and schistes, 150- 700 m. Flowering October through April; fruiting November through September.

DESCRIPTION

Shrubs and trees

3.5- 10 m.

Branchlets

Terete; internodes> 5 mm.

Leaves

Coriaceous, 2 per node; petioles (1.5-) 3-6 mm, sometimes slightly sulcate; blades (4.5-)6.5-10.5 × (-2.0)3.0-5.0(-6.0) cm, elliptic to occasionally ovate, base mostly cuneate to occasionally rounded, surface undulate, margin moderately to strongly and irregularly undulate throughout, apex acute, midnerve above sulcate, secondary veins flush above and below, oil glands of lower surface dense and prominent.

Inflorescence

1.0- 4.5 cm, pedicels 0.2-0.8 cm, racemes or panicles, mostly naked on branches proximal to leaves or axillary, extrafloral bracts absent or scale-like.

Bracteoles

1-2 mm, narrowly elliptic or (less so) narrowly triangular, sparsely sericeous.

Hypanthium

(1.5-)2-4.5 × 2-3 mm, campanulate or rarely obconic, surface smooth, sparsely to moderately sericeous; ovary apex sparsely hairy.

Calyx

Lobes 5, 1.5-2.0 mm, broadly rounded, glabrous above, glabrous to sparsely sericeous below, green.

Petals 3.5-4.5 × 3.5-4 mm, ciliate but otherwise glabrous.

Filaments 3-5 mm; anther sacs 0.3-0.4 mm.

Style

4.5-6 mm, sparsely sericeous.

Fruits

8-12 × 6.5-12 mm, subglobular to globular, base rounded, maturing yellow-green to reddish to reddish-black; seeds 4-12.

REMARKS

The species is easily diagnosed by the inflorescences on naked branches and elliptic, acute leaves with undulate margins. The bark of branchlets often breaks into small rectangular flakes. Gossia ramiflora sp. nov. somewhat resembles G. clusioides , but the latter has a flat leaf margin, lowermost inflorescences axillary, and petals that are tomentose below. The species also resembles G. vieillardii , but leaves of the latter mostly have flat margins, are a lighter shade of green, and the fruit often tapers at the base.

Specimens from Pic Noir north of Farino have shorter petioles, more rounded leaf bases, somewhat shorter inflorescences, and slightly smaller flowers than average. The collection from Pouembout is a shrub with more diminutive leaves. The margins of the leaves of Munzinger 7207 are atypical in being sinuous only distally.

Two specimens previously identified as G. ramiflora sp. nov. may represent an undescribed species. They include Munzinger 7207 & Cantrill (MPU395687, P 01031545) and Munzinger et al. 7261 (CANB n.v., MO-6630977, MPU028536, P01044671). They resemble G. ramiflora sp. nov., but their leaf blades are larger than normal with margins barely if at all irregular, and the blades of the former are slightly bullate in some areas. These specimens also occur over sedimentary volcanics, in contrast to the more typical substrates of volcanics and schists; the latter specimen also is south of the known range of G. ramiflora sp. nov.

Figures

FIG. 20. — Distribution maps of Gossia pancheri (Brongn. & Gris) N. Snow, G. ramiflora N. Snow, sp. nov. and G. virotii (Guillaumin) N. Snow.

FIG. 21. — A-D, Gossia pancheri (Brongn. & Gris) N. Snow: A, flowering branch with details of abaxial leaf venation (offset on right); B, detail of flower prior to anthesis; C, longitudinal section of flower bud showing bilocular ovary with axile placentation; D, leaf and fruits; E-I, Gossia ramiflora N. Snow, sp. nov.: E, flowering branch; F, details of more or less rectangular flaking bark; G, flowers prior to anthesis; H, detail of flower bud; I, another view of leaf (with detail of sinuous margin) with young fruits. Vouchers: A-C, McPherson 3275 (WELTU); D, McPherson 5019 (NOU); E-H, MacKee 12272 (WELTU); I, Phillips 2105 (NOU). Scale bars: A, D, I, 2 cm; B, C, H, 3 mm; E, 2 mm; F, G, 5 mm.