Eugenia lacistema Sobral, 2013

Sobral, Marcos, 2013, Eight New Atlantic Rainforest Species and Nomenclatural Notes in Brazilian Myrtaceae, Phytotaxa 135 (1), pp. 43-61 : 50-52

1.4. Eugenia lacistema Sobral , sp. nov.

Type: BRAZIL. Bahia: mun. Itacaré, rodovia Itacaré-Ilhéus, ca. 6 km a partir da sede do município. Assentamento da Marambaia. Mata Higrófila Sul Baiana , 11 Nov. 1998, A.M. Amorim, V.F. Mansano & S.C. Sant'Ana 2650 (holotype CEPEC , isotypes RB , SP ).

Figure 4 .

This species is related to Eugenia platyphylla , from which it differs by the larger inflorescences with densely imbricate, lignose bracts and smaller pedicels.

Tree 5– 8 m. Twigs glabrous, grey, internodes 25–35 × 3–5 mm, complanate. Leaves with petioles 5–10 × 1.5– 2.5 mm, adaxially flat, dark when dry; blades elliptic to widely lanceolate, 82–160 × 42–73 mm, 1.7–2.4 times longer than wide, slightly discoloured when dry, dark brown or dull dark green, with glandular dots up to 0.1 mm in diameter and about 20 per square milimeter, visible through light, occasionally somewhat raised on both sides; apex widely acute, sometimes the tip wrinkled when dry; base cuneate, decurrent along the petiole; midvein plain to moderately raised adaxially, strongly raised abaxially at least along the proximal half and sometimes lighter than the surface; lateral veins 14 to 17 at each side, moderately raised on both sides, a little more so abaxially, leaving the midvein at angles of 60–80 degrees; marginal veins two, the inner one 2.5–6 mm and the outer one 1–2 mm from the margin, the margin itself revolute. Inflorescences axillary and ramiflorous, racemiform, when ramiflorous with up to four axes arising per node, the axis 3–6 × 2 mm, with up to 14 decussate pairs of densely imbricate hemispheric, thick and somewhat lignified bracts 0.4–0.5 × 1 mm, with up to four flowers per axis; pedicels 2–3 × 0.5–0.9 mm, in fruiting specimens to 5 mm long, strongly complanate, with sparse simple glistening trichomes to 0.1 mm; bracteoles triangular, 0.5–1.1 × 1 mm, abaxially with scattered trichomes as the pedicels; flower buds not seen; calyx lobes four, widely ovate, unequal, the external ones to 1 × 1.5 mm, the internal ones to 1.5 × 2 mm; stamens and petals not seen; staminal ring round to subquadrate, 1.5–2 mm in diameter, with brown simples trichomes 0.1–0.2 mm, staminal scars about 60; style to 4 mm, stigma punctiform; ovary glabrous, bilocular with 10 to 13 ovules per locule. Fruits globose or subglobose, red when ripe, 6–9 mm in diameter, crowned by the calyx-lobes, the staminal ring somewhat excavated and simulating a calyx tube; seed one per fruit, subglobose, the testa light brown, not adhering to the endocarp and easily detachable from the embryo, this with fused and undistinguishable cotyledons and no sign of hypocotyl.

Distribution, habitat and phenology:—this species was collected along the coastal Atlantic Rainforest in the northeastern Brazilian state of Bahia. It is a small forest tree, and was colleted with flowers in April and November and fruits in February.

Conservation:— Eugenia lacistema is presently known from four gatherings from three municipalities of southern Bahia. The municipalities of Canavieiras and Una are contiguous and occupy an area of 2,500 km 2 ( IBGE 2012), Itacaré has an area of 737 km 2 ( IBGE 2012); all these areas have been intensely surveyed by the staff of the Cacao Research Center (CEPEC), and there are 23,596 gatherings registered for these municipalities ( CRIA 2012), resulting in an average of over seven collections per square kilometer, what can be considered a good ratio of collections compared to the mean collection density in Brazil ( Sobral & Stehmann 2009). The scarcity of collections of this species may therefore be considered indicative of its rarity, especially considering that between the municipalities of Itacaré and the other two is the municipality of Ilhéus, with 1,760 km 2 and 22,837 collections (13 collections / km 2), where this species has apparently not yet been collected. The total known range of the species would then occupy about 5,000 km 2, fitting the IUCN criteria for Vulnerable (VU), since the total extent of occurrence is less than 20,000 km 2 (criterion VU B1, IUCN 2001), it exists at no more than 10 locations (criterion B1a), and there is a continuing decline in the quality of its habitat (criterion B1b(iii)) since southern Bahia has been severely deforested and is suffering intense anthropic interference.

Affinities:—this species is related to Eugenia platyphylla O.Berg (for description see Berg 1857–1859), also collected in Bahia, from which it is distinguished by the following characters:

1. Petioles to 6 mm; blades with midvein strongly prominent on both sides; inflorescence axis less than 3 mm, with triangular bracts, these mostly chartaceous and deciduous, not decussate along the axis; pedicels 6–14 mm. ................. ....................................................................................................................................................... Eugenia platyphylla

—. Petioles 5–10 mm; blades with midvein plain or moderately prominent adaxially; inflorescence axis 3–6 mm, with ovate bracts, these lignified, persisting and densely decussate along the axis; pedicels 2–3 mm ... Eugenia lacistema Etymology:—the epithet is allusive to the resemblance of the inflorescences to those of the genus Lacistema Swartz ( Swartz 1788) from the Salicaceae , due to its densely imbricate bracts.

Paratypes:— BRAZIL. Bahia: mun. Canavieiras, entrada à direita ca. 14 km da estrada de Canavieiras para Una, ca. 3,2 km da entrada. Região do Cotovelo , 15 ° 33' S, 38 ° 58'W, 18 Feb. 2003, P. Fiaschi, J.L. Paixão, S.C. Sant'Ana & J.G. Jardim 1321 ( CEPEC); mun. Una, Reserva Biológica do Mico-Leão (Ibama), entrada no km 45 da rodovia BA-001 Ilhéus/Una. Região da mata higrófila sul-bahiana , 15 ° 09' S, 39 ° 05'W, Picada da Bandeira , 15 Apr. 1993, J.G. Jardim, A. Amorim, S.C. de Sant'Ana, E.B. dos Santos & J.L. Hage 114 ( CEPEC, HUFSJ); 13–14 Jul. 1993, J.G. Jardim, L.A. Mattos Silva, S.C. Sant'Ana & E.B. Santos 165 ( CEPEC); idem, J.G. Jardim, L.A. Mattos Silva, S.C. Sant'Ana & E.B. Santos 193 ( CEPEC) .

Figures

FIGURE 4. Eugenia lacistema—holotype (scale: 50 mm); insert: inflorescences with fruits (from Jardim 193; scale: 10 mm).