Eugenia richardii (Blume) N. Snow, Callm. & Phillipson, 2015

Snow, Neil, Callmander, Martin & Phillipson, Peter B., 2015, Studies of Malagasy Eugenia - IV: Seventeen new endemic species, a new combination, and three lectotypifications; with comments on distribution, ecological and evolutionary patterns, PhytoKeys 49, pp. 59-121 : 81-83

publication ID

https://dx.doi.org/10.3897/phytokeys.49.9003

persistent identifier

https://treatment.plazi.org/id/D3D9A03B-5130-57F6-AF55-688FC4139723

treatment provided by

PhytoKeys by Pensoft

scientific name

Eugenia richardii (Blume) N. Snow, Callm. & Phillipson
status

comb. nov.

Eugenia richardii (Blume) N. Snow, Callm. & Phillipson comb. nov. Isotype: http://sonneratphoto.mnhn.fr/2012/08/23/1/P00118150.jpg

Basionym.

Jossinia richardii Blume in Mus. Bot. 1: 123. 1851.

Type.

MADAGASCAR. Prov. Antsiranana: forêt à Vohémar, [13°21'30"S, 50°00'30"E], comm. 1837, J.M.C. Richard 119 (holotype: L [L0009467]!; isotype: P [P00118150]!).

Description.

Shrubs 2-4 m tall; ca. 4 cm dbh; bark of main bole rough, grayish-brown. Branchlets terete, lightish gray-brown (dried); internodes short, (0.5-)1.5-2.3 cm; epidermis smooth but becoming fissured and flaking on older internodes, indumentum moderately dense of minutely dibrachiate trichomes; oil glands common, and somewhat prominent, and protruding above surface. Leaves mostly evenly distributed along branchlets, coriaceous, slightly discolorous, surfaces matte. Axillary colleters absent. Petioles 1-2 mm, slightly sulcate but mostly flush adaxially, glabrous. Leaf blades 2.5-4.5 × 1.6-2.5 cm, elliptic; base rounded to somewhat cuneate; apex broadly obtuse to rounded; margins slightly revolute; adaxial surface glabrous, oil glands dense upon emergence but fading as blade thickens, midvein broadly but slightly sulcate proximally; abaxial surface resembling adaxial, secondary veins indistinct or not visible, intramarginal vein 1.0-1.5 mm from margin at midpoint of blade. Inflorescence a monad arising in terminal leaf axils. Anthopodia (short internode between base of hypanthium and subtending bracteoles) present, 1-2 mm. Pedicels 1.0-1.4 mm, firm but slightly bowed, glabrous. Bracteoles 2, 0.8-1.0 × ca. 1.0 mm, ovate, minutely hairy on margins near apex. Hypanthium 4-5 mm, cupuliform to obconic, glabrous but evidently exuding salt, oil glands common to dense; ovary apex densely short-hairy. Calyx lobes 4, ca. 4 × 4 mm (material limited), oblong, apex obtuse, glabrous, greenish. Petals 9-10 × 6-9 mm, widely elliptic to widely obovate, sparsely short-ciliate on margins, thin (nearly transluscent), pinkish, oil glands sparse to common but prominent. Stamens ca. 70-100, multiseriate; anthers ellipsoid, 0.6-0.8 mm, sub-basifixed, connective with a single apical gland. Filaments 3-9 mm, white; ovary apex densely short-hairy. Styles 9-10 mm, glabrous; stigma narrow. Berries unknown.

Phenology.

Flowering August; fruiting January and likely commencing in late August (unconfirmed).

Distribution.

Known from the north-eastern coastal region of Madagascar in Antsiranana Province, from Orangéa to about 140 km along the coast near Vohemar (Fig. 2).

Habitat and ecology.

Littoral forests over sand, inland from the ocean shore less than 1 km; elevation 10 m.

Conservation status.

With an EOO of 358 km2, an AOO of 36 km2 and three subpopulations, one of which is situated within a proposed protected area that currently holds a temporary protection status (Oronjia), Eugenia richardii is assigned a preliminary risk of extinction of “Endangered” [EN B1ab(iii)+ B2ab(iii)] following the IUCN Red List Categories and Criteria ( IUCN 2012). The species seems to have a highly restricted distribution in dry deciduous forests over sand. The area around Oronjia is mostly degraded as a result of human activities and is under serious threat. A definitive protection of the dry deciduous forests over sand of Oronjia would likely enable the species to be downlisted from the current risk of extinction to “Vulnerable”.

Comments.

Eugenia richardii most closely resembles two species, including Eugenia vanwykiana N. Snow, which differs by its larger leaves with cuneate bases ( Snow et al. 2012). The second fairly close match is Eugenia calciscopulorum , which occurs significantly farther inland (ca. 11 km) than Eugenia richardii and at a higher elevation (ca. 410 m) and over limestone, compared to the sandy substrates of Eugenia richardii . The leaves of Eugenia calciscopulorum have more pronounced secondary veins above and below, retain the pronounced glands into the mature leaf stage, and have a more pronounced petiole.

Eugenia richardii also resembles Eugenia quadriflora H. Perrier, which is known from a single collection in 1961 from east of Lake Alaotra. Both species have thickly coriaceous, densely glandular leaf blades with irregularly undulating surfaces and moderately to strongly recurved margins, and simple flowers arising terminally. However, the leaves of Eugenia quadriflora are sessile with strongly and irregularly recurved blades (although this may reflect to some degree its condition when pressed and dried); in contrast, the leaf blades of of Eugenia richardii are distinctly but shortly petiolate and slightly recurved.

Elsewhere, the leaf morphology of Eugenia richardii somewhat resembles that of Eugenia neofasciculata Bennet from Mauritius (formerly Eugenia fasciculata Guého & A.J. Scott). Based on comparison digitally with an isotype (Lorence DL 1214 (P [P00390098]!), the species are similar by virtue of stiffly coriaceous, densely punctate, obovate-elliptic leaf blades with slightly undulating surfaces and recurved margins that arise from relatively short petioles. However, whereas the adxial petiolar surface of Eugenia richardii is flat, that of Eugenia neofasciculata is somewhat sulcate. In addition, the inflorescence of Eugenia richardii is a terminal pair of flowers with one arising in each leaf axil, whereas that of Eugenia neofasciculata is conspicuously fasciculate (mostly) on naked branches or within leaf axils.

Specimens examined.

MADAGASCAR. Prov. Antsiranana: Vohémar, [12°16'24"S, 49°23'20"E], s.d., L.H. Boivin 2697 (=J.M.C. Richard 134) (P [P00118153]); Orangéa, [12°14'S, 49°22'E], 1-100 m, 22 Jan. 1960, G. G. Cours 5394 (P [P05097489]; Env. de Diégo-Suarez, Orangéa, [12°14'S, 49°22'E], 1-100 m, 22 Jan. 1960, H. Humbert 32245 + G. Cours (P [P05576991]); Ramena, Baie des Sakalava, 3.5 km à l’E du Fokontany Ankorikihely, 12°16'24"S, 49°23'20"E, 17 Aug. 2004, J.B. Leopold 27 + L.J. Razafitsalama, R. Guittou, J. Be, & V. Benjara (CNARP, KSP [KSP000005], MO-6245567, P [P05208542], TAN); Andrafiabe, presqu’île entre Ambolobozobe et Ambolobozokely, 12°29'39"S, 49°34'04"E, 9 Feb. 2005, F. Ratovoson 965 + R. Guittou & D. Elifara (G, MO-6028974, P [P05208572]); Vohémar, [13°21'30"S, 50°00'30"E], s.d., J.M.C. Richard 75 (P [P00118148, P00118149]).

Kingdom

Plantae

Phylum

Tracheophyta

Class

Magnoliopsida

Order

Myrtales

Family

Myrtaceae

Genus

Eugenia