Eugenia fortuita M.A.D.Souza & Sobral, 2017

Sobral, Marcos & Souza, Maria Anália Duarte De, 2017, Four new Myrtaceae from Amazonian Brazil, Phytotaxa 307 (1), pp. 55-64 : 59

2. Eugenia fortuita M.A.D.Souza & Sobral , sp. nov.

Type :— BRAZIL. Amazonas : Without municipality, rio Solimões, igarapé Belém, border of creek, restinga baixa, 22 December 1948, R. L. Fróes 23799 (holotype IAN!; isotype ASU). Figure 2 .

Diagnosis: —This species is apparently related to Eugenia spruceana O. Berg (1857 –1859: 257), from which it is distinguished by the longer inflorescences (to 15 mm long versus less than 5 mm in E. spruceana ) and flowers with dense rufescent indumentum (vs. flowers with scattered white trichomes).

Description: —Tree to 10 m. Twigs glabrous, terete, grey when dry, internodes 40–50 × 2–3.5 mm. Leaves with petioles glabrous, semiterete, adaxially sulcate, sometimes blackish when dry, 10–11 × 1.6–2 mm; blades lanceolate, elliptic of somewhat ovate, 120–150 × 50–85 mm, 1.7–2.4 times longer than wide, glabrous, discolorous when dry, dull green or brown adaxially, lighter and uniformly pruinose abaxially; glandular dots about 0.05 mm in diameter, 12–20/mm², occasionally perceptible on both faces but usually visible only when backlit; base obtuse or sometimes finely decurrent on the petiole; apex acuminate in 8–20 mm; midvein finely sulcate adaxially, sometimes only along the proximal half and then plane, strongly raised abaxially; lateral veins finely raised and moderately visible on both sides, 11 to 15 at each side, leaving the midvein at angles 60–70°; marginal veins two, the inner one 3.2–5, the outer one 1–2 mm from the visibly revolute margin, the margin itself with a dark brown girdle to 0.3 mm wide. Inflorescences ramiflorous, racemiform, the axis 4–15 × 1.5–2 mm, with 4 to 8 flowers, moderately covered with of simple brown trichomes to 0.3 mm; bracts triangular, to 1.5 × 1 mm, scarcely pilose or glabrous, sometimes deciduous at anthesis; pedicels 10–11 × 0.8 mm, pilose as the inflorescences; bracteoles rounded or slightly cordate, 1.8–2 × 2.2 mm, adaxially pilose, sometimes basally connate and with margins somewhat hyaline for about 0.5 mm, persisting after anthesis; flower buds globose or obpyriform, 10–11 × 6–7 mm, uniformly and densely covered with rufescent indumentum as the inflorescences; calyx lobes four, in two unequal pairs, pilose on both sides but a little less so internally, the external ones hemispheric, 3.5–4 × 5–6 mm, the internal ones widely ovate, 7–9 × 6–9 mm; petals four, rounded or obovate, to 12 × 10 mm, glabrous or very sparsely pilose; stamens not counted, filaments to 8 mm, anthers elliptic, to 1 × 0.5 mm, apparently eglandular; staminal ring glabrous or sparsely pilose, sometimes subquadrate, 4.5–6 mm in diameter; style 11–15 mm, glabrous, occasionally verrucose, stigma punctiform and papillose; ovary with two locules and 18 to 20 ovules per locule. Fruits globose, uniformly covered with trichomes as the flowers but these less dense, reddish (according to the collection Cordeiro 336), 24–30 mm in diameter; seeds not examined due to the scarcity of available material.

Distribution, habitat and phenology: —This species is known from two localities, one in the northwestern portion of the state of Amazonas —the municipality of São Gabriel da Cachoeira—and the second from a presently unrecognizable place along the Solimões river. Possibly it is a species from terra firme and várzea forests, considering the information in the collection labels; flowers were collected in December and fruits in February.

Conservation:—Considering that this species is known only from two collections made at least 40 years ago and they have no precise location data, it must be considered as DD (Data Deficient) according to the conservation criteria of IUCN (2001).

Affinities: — Eugenia fortuita is apparently related to the widespread Eugenia spruceana (type images: K barcode 000276670, M barcode 0171120; for description see McVaugh 1958: 735), which occur in northern Brazil, Peru ( Govaerts et al. 2017) and French Guiana ( Funk et al. 2007: 436); they are distinguished in the diagnosis. Considering its inflorescence structure, it can be assigned to section Umbellatae according to the phylogenetic scheme presented by Mazine et al. (2016).

Etymology: —The epithet is derived from the Latin word for “accidental” or “happening by chance”, alluding to the scarcity of collections, since the species is presently known from two exsiccates from vague locations and has not been collected along the last 40 years.

Paratype: — BRAZIL. Amazonas: São Gabriel da Cachoeira, alto Rio Negro, estrada Perimetral Norte, a 22 km da cidade de [São] Gabriel das Cachoeiras (sic), 25 February 1975, M.R. Cordeiro 336 (IAN!).

Figures

FIGURE 2. Eugenia fortuita. Holotype.