Eugenia ramosii M.A.D.Souza & Scudeller, 2016

De Souza, Maria Anália D., Scudeller, Veridiana V. & Mendonça, Maria Sílvia De, 2016, Two new species of Eugenia (Myrtaceae) from Central Amazonia, Brazil, Phytotaxa 289 (2), pp. 167-174 : 170-173

Eugenia ramosii M.A.D.Souza & Scudeller , sp. nov.

Type:— BRAZIL. Amazonas: mun. Manaus, Reserva Florestal Adolpho Ducke , 02º53’ S, 59º58’ W, 23 November 1995, J.E.L.S. Ribeiro et al. 1767 (holotype: INPA !; isotypes: G! , K! , MBM !, MG! , SEL! , SP! , U! , UEC! ). ( Figures 2 , 3C–E )

This species is similar to Eugenia diplocampta , from which it may be distinguished by its higher height (to 20 m high vs. to 10 m in E. diplocampta ), short trichomes (vs. long), grooved petioles (vs. cylindrical), blades drying brown (vs. drying black), with campto-brochidodromous venation (vs. acrodromous), inflorescences fasciculate and racemiform in the same plant (vs. fasciculate only), sepals subobovate to orbicular (vs. oblong), and fruits ellipsoid (vs. globose or subglobose).

Tree 6–20 m, 15–35 cm in diameter at body heigth. Plants vegetatively glabrous. Trunk cylindrical, straigth at base. Bark brown or grey-brown, the periderm microfissurate and reticulate, detaching through membranous, papyraceous or woody fragments; scars impressed, brown; live bark brown or reddish-brown. Twigs angular or flattened, brown, glandulose, glabrous or glabrescent. Leaves with petioles 6–12 mm, adaxially grooved; blades elliptic to oblong or slightly ovate, 50–150 × 20–55 mm, coriaceous; apex acuminate; base cuneate or rounded, brown when dry, the adaxial face lustrous, the abaxial face with numerous raised glandular dots; venation campto-brochidodromous, the midvein adaxially convex, the secondary veins arched and raised, the tertiary veins impressed and the intramarginal vein arched, 3.5–5 mm from the margin. Inflorescences in superposed fascicles, occasionally racemiform in the same branch, axillary or ramiflorous ( Figure 2A–B ), strigose, the trichomes brown or ferruginous; bracts scaly, 0.5 × 0.5 mm, bracteoles 1.5 × 1.2–1.5 mm, deltoid or scaly with acute apex, pilose; pedicels 4–27 mm, more than two times longer than the internodes of the axis. Flowers ca. 2 cm in diameter, hypanthium ferruginous, oblong, campanulate or slightly urceolate, occasionally striate when dry, 2.5–3 × 2–2.5 mm, consisting in about 1/3 of the flower bud length, covered with strigose or arachnoid trichomes; globe of the petals to 7 × 5 mm before anthesis; sepals free from each other, orbicular, coriaceous, subglabrous, in two subequal pairs, 4.5–6.8 × 3–4 mm, in bud imbricate and concealing the globe of the petals ( Figure 3C–D ), cucullate at anthesis; petals subobovate or eliptic-oblong, 6–8 × 4 mm, white, glabrous ( Figure 3E ); staminal ring quadrangular, pilose; filaments filiform, ca. 10 mm, anthers oblong to setaceous, 1–1.2 × 0.5 mm, basifixed, rimose, with one conspicuous apical gland; ovary bilocular, with ca. 8 ovules per locule; style 6–10 mm, pilose. Fruits baccaceous, ellipsoid, 15–18 × 11–12 mm, orange when ripe, glandular, the pericarp subcarnose, constricted on apical ends ( Figure 2C ). Seed one per fruit, ellipsoid; cotyledons with raphe and hilum prominent, embryo with adaxial face of the cotyledons contiguous, visible as a trifid fissure along the medial zone of the seed.

Distribution, habitat and phenology:— Eugenia ramosii grows in plateau and hillsides forests or in open vegetation with sandy soil (“campinarana”), in the central Amazonian municipalities of Manaus and Itacoatiara. Flowers were collected from October to December and ripe fruits in April and May.

Etymology:—The epithet honors Mr. José Ramos, field collector and parataxonomist from the Instituto Nacional de Pesquisas da Amazônia—INPA—who has intensely collaborated in diminishing the number of unidentified specimens in Amazonian herbaria.

Conservation:—This species was collected in two neighboring municipalities only, Manaus and Itacoatiara, and in the absence of better information is appropriate to include E. ramosii in DD (Data Deficient), according to the IUCN criteria (IUCN 2016).

Affinities:— Eugenia ramosii morphologically reminds Eugenia diplocampta Diels (1907: 191) , but is kept apart through its simple trichomes, fasciculate and racemose inflorescences, occasionally striate hypanthium, this also occasionally constricted on both ends and the fruits then resulting ellipsoid. Eugenia diplocampta bears only fasciculate flowers, its hypanthium is smooth (never striate) and the fruits are globose or oblong-cylindrical; the seeds exhibit an vestigial raphe which extends over the cotyledons with a slightly projecting hilum, whereas in E. ramosii the raphe is outstanding covering ca. 2/3 of cotyledons, ending in a double apical elevation with the hilum. The blades of E. ramosii are rigid and never turn dark when dry, as is typical in E. diplocampta . Additionally, E. diplocampta is always a shrub, while E. ramosii is usually a large tree. Both species share the same habitat at Reserva Ducke, although E. diplocampta also grows in lowlands.

Paratypes:— BRAZIL. Amazonas: mun. Manaus, Reserva Florestal Adolpho Ducke , 02º53’ S, 59º58’ W, 24 May 1996, Hopkins & Silva 1588 ( INPA!) ; 14 December 1966, Prance et al. 3631 ( F, INPA!, NY, US) ; 14 November 1995, Souza et al. 155 ( BM!, K!, MG!, PEUFR!, SEL!, SP!, UFMT!, US!) ; 17 May 1996, Souza et al. 248 ( G!, K!, IAN!, INPA1, MBM!, SEL!, SP!, UEC!, US!) ; 15 Nov 1995, Vicentini et al. 1141 ( K!, MG!, MO, NY, RB, SEL, SP, UB). Mun. Itacoatiara, Estrada AM-010, km 202, near Rio Urubu , 19 December 1966, Prance & Pena 3711 ( F, INPA!, NY, US, VEN) ; Estrada AM-010, Km 204 , 21 December 1966, Prance & Pena 3772 ( F, INPA!, NY, US) .

Figures

FIGURE 2. Eugenia ramosii. A. Habit (Ribeiro et al. 1767, holotype). B. An inflorescence racemiform (Id.). C. Fruit (Souza et al. 248). Scales = 1 cm.

FIGURE 3. A–B. Eugenia lisboae (Ribeiro et al. 1758). A. Inflorescence. Note obovate petals (*) and triangular sepals (→), these adpressed to the flower bud. B. Flower after anthesis; note bracteoles basally connate (→), campanulate hypanthium and cucullate sepals. C–E. Eugenia ramosii (Ribeiro et al. 1767, holotype). C. Flower buds in lateral view. D.Apical and apical-lateral view of buds, with sepals concealing the corolla (→). E. Flower, with oblong petals (*).