Myrcia pseudosplendens Sobral & Mazine 2016, sp. nov.
Creators: name: Sobral, Marcos
name: Caliari, Cláudia P.
name: Gressler, Eliana
name: Mazine, Fiorella F.
name: Magenta, Mara
name: Viana, Pedro L.
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Myrtales
Myrtaceae
Myrcia
Myrcia pseudosplendens

description: 5. Myrcia pseudosplendens Sobral & Mazine, sp. nov.
Type:— BRAZIL. Minas Gerais: mun. Santana do Paraíso, propriedade de Fernando Dantas dos Santos, 19°24’42.9’’ S, 42°31’43.4’’ W, 26 January 2011, M. Sobral 13570 (holotype RB!; isotypes BHCB!, HUFSJ!). Figures 6, 7.
This species is related to Myrcia splendens, from which it can be distinguished by its exfoliating bark (not exfoliating in M. splendens), usually wider blades (1.9–2.7 times longer than wide vs. 2.5–4 times longer than wide) and longitudinally sulcate fruits (vs. smooth) crowned by inflexed calyx lobes (vs. erect).
Tree to 8 m high, the cork pale grey and somewhat longitudinally exfoliating. Twigs brown when dry, densely covered with light brown, simple erect trichomes to 0.5 mm, the cortex peeling longitudinally and then becoming grey; internodes 20–55 × 1.5–2 mm. Leaves with petioles 2.5–4 × 1–1.5 mm, moderately sulcate adaxially, with trichomes as the twigs; blades elliptic to lanceolate, sometimes ovate–lanceolate, 67–130 × 35–47 mm, 1.9–2.7 times longer than wide, slightly discolorous when dry, the adaxial face dull green and except for the midvein glabrous or sparsely covered with simple erect trichomes to 0.3 mm, the abaxial face light green and covered by trichomes as the abaxial side, these more dense along the midvein and lateral veins; apex acute to acuminate by 5–15 mm; base cuneate to rounded; glandular dots visible through light, smaller than 0.1 mm in diameter and 5 to 10/mm 2; midvein impressed adaxially and strongly raised abaxially; lateral veins 13 to 20 at each side, moderately visible and sometimes slightly impressed adaxially and markedly raised abaxially, leaving the midvein at angles of 70–80°; secondary lateral veins visible mostly abaxially, with about the same gauge of the main lateral ones; marginal vein 1–2 mm from the margin, the margin itself revolute. Inflorescences axillary and terminal, paniculiform, with 15 to 30 flowers, the axis 40–70 × 1.5–2 mm, sometimes applanate, densely covered with simple erect trichomes to 0.3 mm, with one to three branches, these distally smaller along the axis and forming a triangular profile, respectively 20–35 × 0.5–0.8 mm, 10–20 × 0.5 mm and 4–5 × 0.5 mm, the proximal branch sometimes with a second degree branching to 4 × 0.8 mm; bracts not seen; flowers sessile; bracteoles triangular, one or two, to 1 × 0.5 mm, with trichomes to 0.2 mm; flower buds obovate, 4–5 × 4 mm, uniformly covered with simple erect trichomes, the ovary sometimes a little more densely so; calyx lobes five, unequal between them, widely triangular to ovate, 1–1.5 × 1.5–1.8 mm, adaxially less pilose or sometimes glabrous; petals five, rounded, to 3 × 3 mm, pilose abaxially; stamens about 100, filaments 4.5–5 mm, the anthers subglobose, to 0.4 × 0.3 mm, opening through longitudinal slits, with one apical gland; staminal ring densely pilose, 2.5–2.8 mm in diameter; calyx tube absent; style 5–7 mm, proximally with scattered white trichomes to 0.4 mm, the stigma punctiform and sometimes with trichomes to 0.1 mm; ovary with five moderate longitudinal ridges, two locules and two ovules per locule. Fruits elliptic to oblong, 8–10 × 5 mm, immature, densely covered with simple trichomes to 0.3 mm, with five longitudinal ridges, the calyx lobes persisting and inflexed at the apex, sometimes resembling that they are wanting; seed one per fruit, immature.
Distribution, habitat and phenology:— Myrcia pseudosplendens was collected in rainforests in the hinterland of the state of Minas Gerais, in the municipalities of Marliéria and Santana do Paraíso, at altitudes about 230 m elev.; flowers were collected in December and fruits in January.
Conservation:—This species was collected in the municipalities of Marliéria and Santana do Paraíso, in the central eastern portion of the state of Minas Gerais. Marliérea has an area of 546 km 2 (IBGE 2015b), and there are 5,900 collections from it (CRIA 2015), with an average of 13 collections/km², and Santana do Paraíso has an area of 276 km 2 with 80 collections (IBGE 2015 b, CRIA 2015). with an average of 0.2 collection/km², showing very different collection efforts along the known range of the species. Considering this, and the lack of additional environmental information, it seems adequate to presently consider the species as Data Deficient (DD) according to the IUCN conservation criteria (IUCN 2001).
Affinities:—This species is closely similar to the widespread and very variable Myrcia splendens (Swartz) De Candolle (Swartz 1788: 79, as Myrtus splendens; De Candolle 1828: 244; type image: G barcode 00227975; for description see McVaugh 1958: 659), a species ranging from Central America to southern South America (Govaerts et al. 2015), from which it is distinguished through the characters given in the diagnosis, especially for the consistently longitudinally ridged fruits. In the same way as M. splendens, it matches most of the characters that define informal “group 5” in the phylogenetic scheme of Lucas et al. (2011), such as the paniculiform inflorescence, flowers with absent calyx tube (in some species short but visible) and bilocular ovary.
Etymology:—The epithet is allusive to the striking resemblance of this species with Myrcia splendens.
Paratypes:— BRAZIL. Minas Gerais: mun. Marliéria, Parque Estadual do Rio Doce, região do vinhático, 4 December 1997, W.P. Lopes 503 (VIC!); mun. Santana do Paraíso, propriedade de Fernando Dantas dos Santos, 19°24’42.9’’ S, 42°31’43.4” W, 23 December 2011, M. Sobral 14568 (BHCB!, HUFSJ!, RB!).
description: Published as part of Sobral, Marcos, Caliari, Cláudia P., Gressler, Eliana, Mazine, Fiorella F., Magenta, Mara & Viana, Pedro L., 2016, Seven new southeastern Brazilian species of Myrcia (Myrtaceae), pp. 27-44 in Phytotaxa 247 (1) on pages 36-39, DOI: 10.11646/phytotaxa.247.1.2, http://zenodo.org/record/13676381