Eugenia multilocellata Sobral & M.A.D.Souza, 2022

Souza, Maria Anália Duarte De, Sobral, Marcos & Amorim, Gabriela, 2022, Six new species of Eugenia (Myrtaceae) from Amazonian Brazil, Phytotaxa 536 (3), pp. 197-212 : 205-208

4. Eugenia multilocellata Sobral & M.A.D.Souza , sp. nov.

Type :— BRAZIL. Amazonas : Manaus, rodovia Manaus-Itacoatiara, km 26, trilho LO-2, km 6.5, 2°55’39” S, 59°54’37” W, 11 January 2002, C.V. Castilho 517 (INPA!, holotype). Figures 5 , 6 .

Diagnosis:—This species morphologically resembles Eugenia agathopoda Diels (1907: 192 ; type images G 00227965, K 000276624), but differs by its pilose flowers (versus glabrous in E. agathopoda ) with anthers with multilocellar thecae (vs. unilocellar).

Description:—Tree to 8 m. Plants glabrous except for the inflorescences and flowers. Twigs terete or more or less applanate, grey when dry, slightly longitudinally striate, the internodes 30–50 × 2–5 mm. Leaves with petioles 12–15 × 1.5–3 mm, adaxially sulcate and incurved when dry; blades elliptic, 125–180 × 48–83 mm, 2–2.6 times longer than wide, discolorous when dry, dull dark green adaxially and dull light brown abaxially; base cuneate or widely cuneate; apex acuminate in 4–8 mm and sometimes drying conduplicate; glandular dots scarcely visible on both sides; midvein finely impressed adaxially, markedly raised and darker than the surface abaxially, lateral veins 12–15 at each side, leaving the midvein at angles 60–70°, very slightly raised adaxially, a little more so abaxially; secondary lateral veins and higher order venation of thinner gauge, slightly perceptible on both sides; intramarginal veins two or sometimes three, respectively 4–6 mm, 2–3 mm and 1 mm from the revolute margin. Inflorescences racemiform or fasciculiform, the axis when present 3–13 × 1–2 mm, with up to 6 flowers, the internodes to 5 mm, covered with trichomes to 0.2 mm; bracts not seen; pedicels 6–20 × 1–2 mm, visibly applanate and somewhat wider apically, densely covered by rufescent dibrachiate trichomes to 0.1 mm; bracteoles triangular, 1–1.5 × 1 mm persisting after anthesis, abaxially pilose as the pedicels and with cilia to 0.1 mm; flower buds not seen; the ovary 2.5–3.5 × 2–3 mm, densely covered with dibrachiate brown trichomes to 0.1 mm; sepals four, fused along its very basal portion and this fusion visibly tearing at anthesis, in two more or less unequal pairs, widely elliptic to somewhat oblong-elliptic, to 2–6 × 3–4 mm, at least the largest pair markedly concave and somewhat hooded, adaxially glabrous or with trichomes as the ovary at its basal portion, abaxially uniformly pubescent; petals rounded, the base spathulate, to 4 mm in diameter (according to collection Castilho 517, petals are lilac); stamens not counted, filaments 5–6 mm and anthers 1.5–2 × 0.5 mm, these plurilocular, with 6 to 12 locules per theca; staminal ring subquadrate, to 3 mm in diameter, glabrous or with trichomes as the sepals; calyx tube absent or to 0.2 mm deep, glabrous; style 9 mm, pilose, ovary with two internally glabrous locules and with 25 to 35 ovules per locule. Fruits red when ripe, ellipsoid, 25–28 × 15–20 mm, crowned by the sepals, these strongly incurved; seed one.

Distribution, habitat and phenology:—collected in upland forests (“terra firme”) from the central Amazonian municipalities of Manaus and Novo Aripuanã, at 60–150 m elev.; flowers were collected in January, May and November, and fruits in May.

Affinities:—This species is morphologically related to the northern Brazilian Eugenia agathopoda , with which it is compared in the diagnosis. A noteworthy feature of E. multilocellata is the morphology of the multilocellate or polysporangiate stamens; this character is reported for several families, as Clusiaceae ( Amaral et al. 2017; Stevens 2007: 51; for images see Stevens & Bittrich 2017: 529), Melastomataceae ( Caetano et al. 2020) , Pentaphylacaceae ( Weitzman et al. 2004: 457, under Ternstroemiaceae ; for image see Wang et al. 2005: 491), Rhizophoraceae ( Schwarzbach 2014: 293) and Rubiaceae ( Kirkbride 1985) . Wilson (2011) does not cite this character as occurring in Myrtaceae . Multilocellar stamens are known for us also in the Amazonian Eugenia kerianthera M.A.D.Souza (in Souza et al. 2015: 90); nevertheless, we cannot presently conclude that because of this character these species are phylogenetically related and their overall morphology is very distinct. Regarding its sectional placement, considering either the fasciculiform inflorescences or racemiform with pedicels more than 3 times longer than the internodes, this species may be assigned to Eugenia section Umbellatae , according to the sectional classification proposed by Mazine et al. (2016, 2108).

Conservation:—The muncipality of Manaus has an area of 11,400 km ², from which there are recorded about 100,000 collections, resulting in the high sampling effort of 9 collections/km², quite contrasting the municipality of Novo Aripuanã, with an area of 41,170 km ² from which there are recorded about 1,480 collections—a sampling index of 0.03 collection/km². The Extent of Occurrence (EOO, see IUCN 2012: 11) of this species calculated via Geocat (2020), results in an area of about 1,460 km ²; additionally, the species is presently known from less than five localities; both features are suggestive of the status of Endangered (EN), according to IUCN conservation criteria (IUCN 2012); nevertheless, additional information on population decline or fluctuation is wanting and the status of Data Deficient (DD) is more adequate ( IUCN 2019: 78).

Etymology:—The epithet is derived from the multilocellar character of the anthers.

Paratypes:— BRAZIL. Amazonas: Manaus, Fazenda Esteio, ZF-3, distrito agropecuário da Suframa, November 1979, J. Rankin, J.C. da Costa & Oswaldo 66 (INPA!); ibidem, ARIE-PDBFF, Estrada ZF-3, sítio amostral km 37, parcela CTFS-25ha, quadrat 540 × 200, 2°26’05” S, 59°47’01” W, 10 May 2004, P.A. Pereira 237 (INPA!). Novo Aripuanã, BR-230, rodovia Transamazônica a 400 km de Humaitá, INCRA - Projeto do Rio Juma , 7°15’ S, 60°00” W, 1 May 1985, C.A.C. Ferreira 5945 (ASU, INPA!, K, MO, NY, RB!, US) .

Figures

FIGURE 5. Eugenia multilocellata. Holotype (scale = 50 mm).

FIGURE 6. Eugenia multilocellata. Detail of multilocellate anthers (scale = 1 mm).