Eugenia amosensis N. Snow

Neil Snow, John W. Dawson, Martin W. Callmander, Kanchi Gandhi & Jérôme Munzinge, 2016, New Species, New Combinations, and Lectotypifications in New Caledonian Eugenia L. (Myrtaceae), Candollea 71 (1), pp. 67-81 : 68-70

Eugenia amosensis N. Snow , spec. nova

( Fig. 1 , 2 ).

Typus: New CaledoNia. Prov. Nord: Col d’Amoss , 20°17’16’’S 164°25’42’’E, 13.XI.2002, Munzinger et al. 1488 (holo-: P [ P00354503 sheet 1, P04884668 sheet 2]!; iso-: MO-5841143 !; NOU [ NOU002732 ]!).

Differing from congeneric species in New Caledonia by its relatively long, narrowly elliptic, sessile to subsessile leaves with cordate bases, cauliflorous inflorescence, and densely velutinous indumentum on the pedicels, hypanthium and proximal abaxial portion of the calyx lobes.

Shrubs to 3 m. Branchlets glabrous, eglandular, smooth, the epidermis soon becoming gray and flaking away. Pedicels, hypanthium and lower calyx lobes densely reddish velutinous. Leaves sessile to sub-sessile, coriaceous, venation brochidodromous, discolorous, surfaces matte, evenly distributed along branchlets. Foliar colleters absent. Leaf blades 15.5-37.7 X 5.0- 7.4 cm, narrowly elliptic, base cordate, apex acute, margin flat, secondary and tertiary veins protruding somewhat above; adaxial surface glabrous, midvein raised; abaxial surface moderately to densely glandular (use magnification), secondary and higher-order veins prominent, intramarginal vein prominent, (1.5-) 3-5 mm from margin at midpoint of blade. Inflorescences cauliflorous, ca. 2 cm long, of monads or short (5-flowered) botryoids. Pedicels 2-12 mm, rigid. Bracteoles ca. 0.5 X ca. 1.0 mm (material scant, possibly not fully expanded), hemispherical, broadly rounded apically. Hypanthium cupuliform, ca. 5 mm. Calyx lobes 4, ca. 1-2 mm, dimorphic, apex rounded, more or less glabrous above. Petals 4, 6- 7 X 6-7 mm, oblate, sparsely short-ciliate on margins. Stamens numerous (> 100), multiseriate; filaments length uncertain (material in bud); anthers ca. 0.8 mm, ellipsoid, dorsifixed, eglandular. Style ca. 6 mm (limited material), moderately short-villous in lower half, stigma narrow. Ovary bilocular, placentation axile, ovules ca. 25 per placenta, densely but irregularly placed on somewhat triangular-shaped placenta. Fruit unknown.

Distribution, ecology and phenology. ‒ Known only from the type gathering at Col d’Amos (misspelled as “d’Amoss” on the type specimen) near the northern end of Grand Terre ( Fig. 2 ). Flowering in November, fruiting unknown.

Conservation status ‒ With a single location known outside of the protected area network in a forested area heavily fragmented and regularly damaged by anthropogenic bush fires, E. amosensis is assigned a preliminary IUCN conservation status of “Critically Endangered” [CR B2ab(iii, v)+C2(a)+D].

Notes. ‒ Additional collections are needed to better characterize flowering and fruiting material and their seasons. The long, narrowly elliptic, sessile to subsessile cordate leaves, coupled with the cauliflorous inflorescence with dense velutinous indumentum, collectively diagnose the species among others in New Caledonia. Although a subtle character state, the villous base of the style is also atypical for most in the genus.

Figures

Fig. 1. – Distribution of new species of Eugenia L. in New Caledonia mapped on ultrabasic rocks (light grey) and protected areas (dotted stippling): E. amosensis N. Snow (circle), E. homedeboana N. Snow (squares), E. sicifolia J. W. Dawson & N. Snow (pentagons), E. tchambaensis J. W. Dawson & N. Snow (stars), and E. tiwakaensis J. W. Dawson & N. Snow (crosses).

Fig. 2. – Holotype of Eugenia amosensis N. Snow. [Munzinger et al. 1488, P] [© Muséum national d’Histoire naturelle, Paris. Reproduced with permission]