Eugenia cerradensis Sobral & Faria, 2018

Sobral, Marcos, Faria, Jair E. Q. & Coutinho, Karoline, 2018, Five new Brazilian species of Eugenia (Myrtaceae), Phytotaxa 347 (1), pp. 59-70 : 62-63

2. Eugenia cerradensis Sobral & Faria , sp. nov.

Type:— BRAZIL. Mato Grosso: Cocalinho, margem da MT-100 entre Araguaína e Cocalinho , 31 July 2015, J.E.Q. Faria, M.S. Melo, P.O. Rosa & V.C. Mendes 4915 (holotype UB; isotype RB!) . Figure 2 .

Diagnosis:—This species is morphologically related to Eugenia stictopetala De Candolle (1828: 270) , from which it is distinguished by its pilose leaves (versus glabrous in E. stictopetala ) with proportionally shorter petioles (to 3% of the blade’s length vs. about 7%) and flowers with calyx lobes in two unequal pairs, the largest ones to 2 mm (vs. calyx lobes about same size, up to 1 mm), these concealing at least partially the globe of the petals in bud (vs. globe of petals clearly visible, never concealed by the calyx lobes).

Description:—Tree to 6 m. Twigs light brown, densely covered with simple erect trichomes 0.3–0.5 mm which occasionally conceal its surface, these falling with age and then the twigs turning grey, longitudinally striate; internodes 28–40 × 1.5–3 mm; bases of twigs occasionally with 2 to 4 triangular cataphylls to 2 × 2 mm, glabrous. Leaves with petioles 2–3 × 1–1.5 mm, pilose as the twigs, adaxially sulcate; blades elliptic, widely elliptic or rounded, 70–98 × 49–64 mm, 1.3–1.7 times longer than wide, discolorous when dry, dark dull green adaxially and lighter abaxially, glabrous except for trichomes to 0.3 mm along the midvein adaxially, densely covered with simple erect trichomes to 0.7 mm, soft at touch and not concealing the surface abaxially; glandular dots smaller than 0.05 mm in diameter, 6 to 10/mm², usually visible only when backlit, but sometimes scarcely visible on the abaxial side; base rounded; apex widely obtuse or rounded; midvein impressed adaxially and markedly raised abaxially; lateral veins 6 to 9 at each side, leaving the midvein at angles about 60°, visibly diminishing in gauge distally, moderately raised on both sides, a little more so abaxially and there sometimes yellowish, lighter than the surface; marginal veins two, the inner one somewhat discontinuous, formed by the loops of the lateral veins, 2.5–5 mm from the margin, the outer one more continuous, 1– 1.5 mm from the margin and sometimes formed by the first or second lateral vein that extends along the blade; margin slightly to markedly revolute. Inflorescences ramiflorous, fasciculiform, with an axis 1–3 × 1 mm, densely beset with trichomes to 0.3 mm, with 2 to 6 flowers; bracts not seen; pedicels 2–7.5 × 0.3–0.6 mm, glabrous or with scattered erect trichomes to 0.3 mm; bracteoles widely elliptic or triangular, 1 × 0.7–1 mm, glabrous or with cilia to 0.1 mm, persisting after anthesis, free from each other, abaxially with simple grey trichomes to 0.2 mm; flower buds globose to obovate, 4–5 × 4 mm, mostly glabrous, with scattered rufescent simple hairs to 0.2 mm at the distal portion of the lobes and cilia 0.1–0.2 mm; calyx lobes four, in two ovate, unequal pairs, the outer one to 1–2 × 1.5–2 mm, the inner one to 2–2.5 × 1.5–3 mm; petals four, rounded, to 4–5 mm in diameter (in bud), glabrous, sparsely glandulose, with cilia to 0.1 mm; stamens not counted, the filaments to 4 mm, the anthers ovate, 0.7–0.8 × 0.5 mm, with one dark apical gland; staminal ring glabrous, 2–3 mm in diameter and 0.5–1 mm thick; calyx tube absent; style to 7 mm, glabrous, the stigma papillose, punctiform; ovary with two glabrous locules and 10 to 15 ovules per locule. Fruits globose or oblate, immature, 7–9 × 7–12 mm when dry, crowned with calyx lobes; seed one, reniform, to 11 × 9 mm, the testa pale yellow, easily detachable, with embryo to 9 × 7 mm, homogeneous, with fused cotyledons and no visible hypocotyl.

Distribution, habitat and phenology:—This species is presently known from two collections, from the central western states of Goiás and Mato Grosso, both found in savanna vegetation (“cerrado”); flowers were collected in July and fruits in October.

Conservation:—The two known specimens were collected in two municipalities—Cocalinho, in the state of Mato Grosso, and Hidrolândia, in the state of Goiás —more than 500 km apart, indicating a relatively large extent of occurrence; nevertheless, there are no additional information available about this species. Considering this, it must be scored as DD (Data Deficient) according to IUCN conservation criteria ( IUCN 2001).

Etymology:—The epithet is allusive to the savanna biome in Brazil, the Cerrado, where the species was collected.

Affinities:—This species is morphologically related to Eugenia stictopetala (for a good description see McVaugh (1958: 739), under E. tapacumensis O.Berg ( Berg 1855 –1856: 222; synonym according to Govaerts et al. 2016), from which it is kept apart through the characters listed in the diagnosis. The fasciculiform inflorescences of this species are typical of section Umbellatae , according to the phylogenetic scheme proposed by Mazine et al. (2016).

Paratype:— BRAZIL. Goiás: Hidrolândia, acesso pela BR-153 próximo à divisa Hidrolândia—Aparecida de Goiânia , 165220S, 491458 W, 15 August 2010, J.F.B. Pastore 3107 ( HUEFS!) .

Figures

FIGURE 2. Eugenia cerradensis. Isotype at RB.