Myrceugenia bonita F.C.S.Vieira, 2025

Myrceugenia bonita F.C.S.Vieira , sp. nov.

TYPE:— BRAZIL Bahia: Camacã, Serra Bonita , 15º23’24”S, 39º33’56”W, ca. 850m elev., 02 October 2023, F.C.S. Vieira 3599 (holotype USP!, GoogleMaps isotype JOI!) GoogleMaps .

Figures 1 View FIGURE 1 , 3 View FIGURE 3 .

Diagnosis:— This species is morphologically similar to Myrceugenia miersiana (Gardner) D.Legrand & Kausel (in Legrand 1953: 8; basionym: Eugenia miersiana Gardner, 1845: 103 ), however, the leaves are notably larger and wider, measuring 80–150 × 34–85 mm, the petiole is also larger, reaching dimensions of 14–26 × 2–3 mm and is flat on the upper surface with a very fine groove and two wings, and the sepals are internally glabrous. In contrast, in M. miersiana , the leaves only reach a maximum size of 100 × 30 mm, the petioles measure 2–7 × 1–1.5 mm and are plump or slightly furrowed, and the sepals are densely pubescent adaxially.

Description:— Tree to 6–8 m tall; bark whitish with sheets of papyraceous consistency, light beige on young branches, these covered with simple reddish trichomes; young branches slightly flattened, furrowed; simple, erect trichomes forming a tomentose coating on the pedicels, bracteoles, floral buds, the abaxial side of the leaves and on young branches, which are shed with the growth of the branches. Leaves with the petiole flat on the upper surface, with a very fine groove and two lateral wings, 14–26 × 2–3 mm; lamina chartaceous, ovate–elliptical, 80–150 × 34–85 mm, about 2.5 times as long as wide, beige and reddish to greenish brown on the abaxial surface and olive green to dark brown on the adaxial surface, with translucent glands visible under a magnifying glass, one per reticulum; base attenuate; apex cuneate, with mucron 1–2 × 1–1.2 mm; margin gently revolute, primary vein prominent on the abaxial surface, grooved on the adaxial; secondary veins 9–12 pairs, leaving the midvein at an angle of approximately 70º, slightly grooved on the adaxial side; marginal veins two, the innermost forming arches, about 2–6 mm from the edge, and the outermost one follows the edge of the leaf. Peduncles uniflorous, in rows, positioned vertically within a file, between the shoot and the petiole, 2–4 per leaf axil, covered with simple and dibrachiate trichomes, beige to brown, 18–10 × 1–2 mm; bracts absent; bracteoles oblong, 3.4–4 × 1–1.2 mm, internally flat, without the presence of a protruding vein, completely free at the base, inserted into the peduncle, not reaching the median portion of the flower bud, covering only the ovary; floral buds globose with petals hidden; sepals triangular, 5.6 × 4.5 mm, internally glabrous; petals white orbicular, 4.5–5.5 × 5.5–6.5 mm, densely covered with trichomes externally, sparsely internally; stamens ca. 230, semi-curved in the bud, 2.5 × 0.1 mm; style 5.2 × 0.3 mm, covered with sparse simple hyaline trichomes, stigma punctate; ovary trilocular, 7–9 ovules per locule, 23–25 ovules in total; fruits not seen.

Distribution, habitat and phenology:—The species is endemic to the state of Bahia and is restricted to two mountainous regions: Serra Bonita in the municipality of Camacã, and Serra do Teimoso in Jussari, at elevations of around 800–1000m in montane rainforest. Specimens were collected with flowers from March to October.

Conservation status:—By employing the geographic coordinates of the collections and the use of GEOCAT, the species demonstrates a very limited extent of occurrence (EOO = 272 km ²), and area of occupancy (AOO = 12 km ²), and an observed population size estimated to be fewer than 50 mature individuals. These findings suggest that Myrceugenia bonita meets the criteria for classification as EN (endangered).

Affinities:—This species resembles the widespread southeastern and southern Brazilian Myrceugenia miersiana (for description see Legrand & Klein 1970: 395 and Landrum 1981b: 99); with which it is compared in the diagnosis.

Etymology:—The species is named in honor of its specific collection location, Serra Bonita in the municipality of Camacã, situated in the state of Bahia, Brazil.

Paratypes:— BRAZIL. Bahia: Arataca, RPPN Caminho das Pedras , em trilha de acesso ao Peito-de-Moça., 15º10’25”S, 39º20’30”W, ca. 1000m elev., 05 August 2006, M.M.M.Lopes, P.Labiak, J.Paixao, L.Gomes 13331 ( ASU *, NYBG *, CEPLAC!). GoogleMaps Camacã, 9, 7 km W de Camacã na estrada para Jacarecí , daí 6 km SW na estrada para a RPPN e Torre da Embratel . Trilha do mirante, até a Torre, 06 June 2006, M.M.M. Lopes 813 ( NYBG *, RBR *, UB!). Jussari, Fazenda Serra do Teimoso . Reserva Serra do Teimoso . Perto do topo da montanha, em área perto do Ribeirão da Bica, 15 March 2003, W.W. Thomas 13331 ( UB!, CEPLAC!).