Eugenia potiraguensis Coutinho & M.Ibrahim, 2015

Coutinho, Karoline, Oliveira, Marla Ibrahim Uehbe De & Funch, Lígia Silveira, 2015, Four new species of Eugenia (Myrtaceae) from the Caatinga and Atlantic Forest of northeastern Brazil, Phytotaxa 234 (3), pp. 215-226 : 222

4. Eugenia potiraguensis Coutinho & M.Ibrahim sp. nov. ( Figures 4 and 5 )

This species is similar to Eugenia plicata Niedenzu (1897:81) , but differs by having glabrous midvein, petioles 3–6 mm long, calyx lobes of equal length, staminal ring ca. 3 mm in diameter.

Type: — BRAZIL. Bahia: Potiraguá, 15°42’12”S 39°34’32”W, 10 June de 2004, P. Fiaschi et al. 2287 (holotype CEPEC!, isotype NY).

Tree 5 m high; young twigs brownish, glabrous or puberulous, adult branches grayish, glabrous. Leaf blades 29–8 × 8–22 mm, chartaceous, lanceolate, flat, reticulate; apex acute; base cuneate; margins slightly revolute and/or undulate, glabrous; glandular dot on both sides 0.1–0.7 mm diameter, 10–14 per square millimeter; venation acrodromous; midvein sulcate above, prominent below, glabrous on both sides, lateral veins 14–23, erect, leaving the midvein at 55°–60°, glabrous, barely visible abaxially, all confluent with the marginal vein; marginal vein 0.3–0.9 mm from the border; petiole 3–6 mm, channeled, glabrous. Inflorescences terminal or axillary, 2–4 flowered; rachis ca. 10 mm long; pedicels 17–27 mm, brownish; bracts, bracteoles and flower buds not seen; calyx lobes four, 4–5.1 × 1.2–1.9 mm, deltoid or linear, equal between them, apex acute or rounded, ciliate, glabrous, abaxially with glandular dots; petals not seen; hypanthium 1.7–2.2 × 1.8–1.9 mm, not costate, pubescent, glandular dots absent; staminal ring ca. 3.2 mm diam., pilose; stamens not seen; style ca. 5.0 mm long, glabrous with translucent dots; ovary, bilocular, glabrous, number of ovules not seen. Fruit not costate, globose, puberulous, verrucose; seed one; ca. 7.3 × 3.7 mm globose; glandular dot absent.

Etymology:— The specific epithet refers to the locality in which the species was collected.

Phenology:— Fruits in June.

Distribution and habitat:— Eugenia potiraguensis was collected in the southern region of Bahia State in the municipality of Potiraguá and also 350 km distant in the northeastern region of the same state in the municipality of Cachoeira. Although both sites are within the Atlantic Forest domain, the former is located at 180 m elev. in a subhumid to dry climate, with 900 mm of rainfall per year and an average annual temperature of 23 °C. The regional vegetation is composed of semideciduous and seasonally deciduous forests. The Cachoeira area is almost at sea level, the regional climate is tropical humid, with an average of 1800 mm of rainfall per year and an average annual temperature of 25 °C. The regional vegetation is composed of dense evergreen and seasonal semideciduous forests ( Tomasoni & Tomasoni 2005). The distance between the specimens of E. potiraguensis collected suggests its ample distribution, although the Atlantic Forest biome has become quite degraded, especially in the survey areas.

Morphological comments: — Eugenia potiraguensis is similar to E. plicata as they both have leaves 29–90 mm long, lanceolate and chartaceous, with undulate and/or revolute margins. They can be distinguished by E. potiraguensis having a glabrous midvein, petiole 3–6 mm long, calyx lobes equal, and stamen disk ca. 3 mm diam. Eugenia plicata , on the other hand, has a puberulous midvein, petiole 0.5–1.4 mm long, calyx lobes unequal, and stamen disk ca. 2 mm diam.

Conservation status:— Eugenia potiraguensis was collected in two municipalities where collection efforts have only been incipient and, according to the CRIA website (2015), 4325 collections have been recorded from Cachoeira (395 km ²) and 355 from Potiraguá (985 km ²), yielding a sampling ratio of ~3.4 specimens/km². However, as the rarity of this species may be attributed to few collections, it seems more appropriate to adopt the IUCN category DD (deficient data; IUCN 2015).

Paratype:— BRAZIL, Bahia, Cachoeira, 12°32’00”S 39°05’00”W, September 1980, Grupo Pedra do Cavalo 781 (ALCB!, CEPEC!, BAH, HUEFS!, IPA, RB).

Figures

FIGURE 4. Eugenia potiraguensis Coutinho & M.Ibrahim A. Habit. B. Detail of fruit (scale 1 cm).

FIGURE 5. Distribution map of Eugenia caatingicola Coutinho & M. Ibrahim, E. funchiana Coutinho & M. Ibrahim, E. coccinea Coutinho & M. Ibrahim, and E. potiraguensis Coutinho & M. Ibrahim in Brazil.