Myrcia alatiramea Sobral & E.Lucas, 2015

Sobral, Marcos, Faria Jr, Jair E. Q., Ibrahim, Marla U., Lucas, Eve J., Rigueira, Dary, Stadnik, Aline & Dcnat-Ufsj, Daniel Villaroel, 2015, Thirteen new Myrtaceae from Bahia, Brazil, Phytotaxa 224 (3), pp. 201-231 : 214-216

7. Myrcia alatiramea Sobral & E.Lucas , sp. nov. Type:— BRAZIL. Bahia: mun. Boa Nova, Parque Nacional de Boa Nova , setor sul, ramal para a Fazenda Liberdade , 14º28’45” S, 40º07’11” W, 917 m, 7 January 2013, L. Y. S. Aona, G. M. Costa, W. G. Fonseca, J. G. Jardim & S. Simões 1952 (holotype RB!; isotypes HURB, K). Figure 8 .

This species is apparently related to Myrcia anceps , from which it is distinguished through its leaves with relatively shorter petioles (ratio blade length: petiole length 45–55:1 versus smaller than 30: 1 in M. anceps ), larger blades (to 280 mm versus to 180 mm) with smooth adaxial surface (vs. usually somewhat bullate), up to 35 lateral veins at each side (vs. up to 20) and rounded bases (vs. cuneate), pauciflorous inflorescences (with up to 60 flowers vs. more than 100 flowers) and calyx tube conspicuous (vs. absent).

Tree to 7 m. Plants glabrous except for scattered trichomes in the flowers. Twigs light brown, with raised glandular dots to 0.1 mm in diameter, applanate and with two marked longitudinal crests 1–1.5 mm wide; internodes 45–70 × 3–4 mm without the crests (with them 5–7 mm wide). Leaves with petioles 3–6 × 2.2–2.8 mm, adaxially canaliculate, darker than the blades when dry; blades narrowly elliptic to oblong, 170–280 × 35–67 mm, 3.4–5 times longer than wide, moderately discolorous when dry, lighter abaxially; glandular dots about 6/mm², up to 0.1 mm in diameter, occasionally visible abaxially; apex acuminate in 12–35 mm; base widely rounded; midvein finely sulcate adaxially and strongly raised abaxially; lateral veins 30 to 35 at each side, leaving the midvein at angles of 80–90°, visible and moderately raised on both sides, with secondary lateral veins sometimes about the same gauge; marginal veins two, the inner one 3–3.2 mm, the outer one 0.8–0.9 mm from the margin, the margin itself sometimes slightly revolute and with a yellow girdle to 0.2 mm wide. Inflorescences at the axils of leaves or at the apex of branches, not subtended by leaves, paniculiform, to 180 × 3 mm, ramified along the distal half, with four to five secondary branches strictly opposite one to each other, the proximal secondary branches about 40 mm, the more distal ones about 5 mm long, the rachis applanate and ridged as the twigs, with about 60 sessile flowers; bracts lanceolate, to 3.5 × 0.8 mm; bracteoles lanceolate, to 1.5 × 0.5 mm, deciduous at anthesis; flower buds obpyriform, to 5 × 4 mm, with very scattered light simple trichomes smaller than 0.1 mm, the ovary clearly distinct from the calyx lobes; calyx lobes five, free, about the same size, widely ovate, 1–1.2 × 2–2.5 mm, with trichomes as the buds on both sides, a little more dense adaxially; erect at anthesis; petals five, white, elliptic, 4–5 × 2.5–3 mm; stamens not counted, to 6 mm, the anthers elliptic, to 0.7 × 0.3 mm, eglandular; staminal ring to 2 mm in diameter, with scattered trichomes; calyx tube to 1 mm deep, pilose as the lobes; style to 8 mm, the stigma punctiform; ovary bilocular, with two ovules per locule. Fruits not seen.

Distribution, habitat and phenology:—This species is presently known only from the type collection, from Atlantic rainforests of the municipality of Boa Nova, at the eastern portion of Bahia; flowers were collected in January.

Conservation:—The municipality of Boa Nova has been relatively well surveyed botanically, with 4,061 gatherings ( CRIA 2015) for an area of 868 km ² ( IBGE 2015), resulting in an average of 4.7 collections/km²; the fact of this species being known for only one collection may be an indicative of its rareness; additionally the area of the municipality, if considered as the extent of occurrence for the species, would also be suggestive of an endangered (EN) status. Nevertheless, in the absence of additional information on the habitat, it must be scored as DD (Data Deficient) according to IUCN conservation criteria ( IUCN 2001).

Affinities:—Some characters of this species, as the regularly branching inflorescences,free calyx lobes and bilocular ovaries, match the characters used by Lucas et al. (2011) in their conspectus of the genus Myrcia for characterizing their “group 5”, which encompass species of Myrcia sect. Myrcia sensu McVaugh (1969) ; nevertheless, this species is here only tentatively assigned to this group, since the presence of a marked calyx tube is a deviant character. Myrcia alatiramea is apparently related to Myrcia anceps (Sprengel) O.Berg (basionym: Myrtus anceps Sprengel, 1821: 170 ; Berg 1857 –1859; type image: BR barcode 0000005233698), with which it is compared in the diagnosis.

Etymology:—The epithet is derived from the Latin words for “winged twigs”, alluding to the longitudinal crests along the twigs of the species.