Eugenia mammifera Costa-Lima

Costa-Lima, James Lucas Da & Chagas, Earl Celestino De Oliveira, 2018, Six new species of Eugenia (Myrtaceae) from the Atlantic Forest of northeastern Brazil, Phytotaxa 373 (3), pp. 211-220 : 216-218

5. Eugenia mammifera Costa-Lima & E.C.O.Chagas, sp. nov. ( Fig. 3A–D )

Eugenia mammifera is similar to E. coffeifolia but differs by the leaf blades that are elliptic (vs. widely elliptic) and acute to attenuate-cuspidate (vs. abruptly cuspidate to caudate) at the apex, secondary veins 14–17 (vs. 8–10) per side, eciliate (vs. ciliate) calyx lobes, and 8-costate (vs. smooth) fruits that are constricted (vs. non-constricted) at apex.

Type: — BRAZIL. Alagoas: Mun. Mar Vermelho, Fazenda Canadá, 8 May 2009 (fl, fr), E. C. O. Chagas, M. C. S. Mota [as Chagas-Mota], A. I. L. Pinheiro & S. Cavalcanti 3773 (holotype MAC!).

Trees, ca. 6 m tall; bark exfoliating; branches glabrous, brownish when young, greyish when old. Petioles 5–10 mm long, glabrous. Leaf blades 7.2–16.7 × 3.1–5.4 cm, elliptic, membranaceous, with minute glandular dots more visible adaxially, discolorous, glabrous, apex acute to attenuate-cuspidate, margin slightly revolute, base acute; midvein impressed adaxially, prominent abaxially, secondary veins 14–17 per side, with distinct gridiron pattern, impressed adaxially, prominent abaxially, the marginal vein 3–5.5 mm from the margin. Inflorescences axillary, glomeruliform, 1–2 crowded in an axis, 0.5–2.5 mm long; bracts and bracteoles 0.6–1.5 mm long, cymbiform, with visible keel, acute at apex, pubescent, indumentum cinereous when dry; pedicels 0.8–1.5 mm long, pubescent; hypanthium glabrous, cinereous when dry; sepals 4, in unequal pairs, the outer ones 3–4.5 × 3.5–5 mm, the inner ones 2.2–3 × 1.8–2.5 mm, hemispheric, glabrous or sometimes with lanose indumentum only at apex, with visible dots on outer surface, rounded at apex, margin shortly ciliate; petals not seen; stamens ca. 240; staminal ring pubescent; style 8–12 mm long, glabrous, stigma capitate, pilose; ovary glabrous internally, 2-locular, ovules 9–12 per locule. Fruits 18–22 × 9–11.5 mm, ellipsoid, glandular-rugose, 8-costate, constricted at apex, crowned by the calyx lobes, lobes erect; 1-seeded.

Etymology: —The epithet refers to the fruits shape, which are constricted at apex and resemble women’s breasts.

Distribution and habitat: — Eugenia mammifera occurs in the state of Alagoas, in northeastern Brazil, where it grows in the rainforest subcanopy.

Conservation status: — Eugenia mammifera , like E. cambemba , can be considered as Critically Endangered [CR B12ab(i,ii,iii)], according to IUCN (2017) criteria. Both species suffer the same threats because they occur in the same small forest fragment.

Paratypes: — BRAZIL. Alagoas: Mun. Mar Vermelho, Fazenda Canadá , 8 May 2009 (fl), E. C. O. Chagas [as Chagas-Mota] et al. 3581 ( MAC!) ; ibidem, 8 May 2009 (fl), E. C. O. Chagas [as Chagas-Mota] et al. 3596 ( MAC!) .

Discussion: — Eugenia mammifera has flowers arranged in glomerules like E. cambemba (described here) and also fits in the concept of Mazine et al. (2016) for Eugenia sect. Umbellatae . Eugenia mammifera is similar to Eugenia coffeifolia De Candolle (1828: 272) by the leaf blades with secondary veins in a distinct gridiron pattern, intramarginal vein far from the margin, glomerate inflorescences in the axils of leaves or at leafless nodes, and sessile flowers, but the features to distinguish both are presented in the above diagnosis. Furthermore, both species do not co-occur: Eugenia coffeifolia occurs in the Antilles, Venezuela, Suriname, French Guiana and northern Brazil ( Holst & Kawasaki 2000), especially in the Amazonian domain, while E. mammifera is restricted to Atlantic Forest in Alagoas, in northeastern Brazil. Eugenia mammifera can also be confused with E. cambemba but can be readily distinguished by the number of secondary veins on the leaf blades, visible veins on the blade surfaces, distance of the marginal vein from the margin, and the surface of the fruits (see comments under E cambemba ).

Figures

FIGURE 3. Eugenia mammifera. A. Fruiting branch, in sicco (scale: 4 cm). B. Flowering branch. C. Old flowers (without petals and stamens). D. Immature fruit. Eugenia palmarina. E. Flowering branch, highlighting the inflorescence architecture. F. Inflorescence. G. Immature fruit. H. Flowering branch, in sicco (scale: 5 cm). All photographs by the authors.