Microlicia ferricola Versiane, M.J.R.Rocha & R.Romero, 2024

Versiane, Ana Flávia Alves, Rocha, Maria José Reis Da, Santos, Amanda Alves & Romero, Rosana, 2024, Microlicia ferricola (Lavoisiereae), a new species of Melastomataceae from the Iron Quadrangle, Minas Gerais, Brazil, Phytotaxa 671 (1), pp. 105-112 : 106-110

Microlicia ferricola Versiane, M.J.R.Rocha & R.Romero , sp. nov. ( Figs. 1–2 ).

Diagnosis:— This species is readily recognized by its leaves lanceolate to elliptic-lanceolate with attenuate bases, setose at the apices, short petioles, campanulate-oblong hypanthia, and long-triangular sepals. The branches, leaves, hypanthia, and sepals are green-reddish to reddish and moderately covered with glandular trichomes. Moreover, the stamens are dimorphic and bicolorous with tetrasporangiate anthers.

Type: — BRAZIL. Minas Gerais: Belo Horizonte, Parque Estadual da Serra do Rola-Moça, estrada de acesso à cachoeira Duas Quedas , lado direito, cerca de 200 m do ponto de ônibus, 20°02’35”S, 43°59’19”W, 31 August 2022 (fl., fr.), M.J.R. Rocha, A.A. Santos & A.P.M. Fonseca 1437 (holotype: IBIUEMG!; isotypes: BHCB!, HUFU!, RB!) .

Subshrubs, 15–30 cm tall, erect, much branched, branches slender, dichotomous. Branches quadrangular, sometimes slightly winged, green-reddish to reddish, sparsely to moderately covered by glandular trichomes (trichomes 0.2–0.4 mm long); nodes thickened, internodes 1.5–3.5 mm long, sparsely to moderately covered with glandular trichomes. Leaves ascending, slightly imbricate, not amplexicaul, concolorous, green or green-reddish to reddish, or discolorous, abaxial surface green, adaxial surface reddish, petioles 0.09–0.13 mm long, flat, glabrous; blades 3–6.5 × 0.5–1 mm, chartaceous, lanceolate to elliptic-lanceolate, apices acute, setose (trichomes 0.1–0.5 mm long), bases attenuate, margins entire, flat, with glandular trichomes or glabrous, adaxial surfaces glabrous or rarely with few glandular trichomes, abaxial surfaces sparsely to moderately covered with glandular trichomes (0.2–0.4 mm long), 3-veined, main veins visible on both surfaces, secondary veins visible only on the adaxial surfaces, tertiary veins absent. Flowers solitaries, lateral or at the apices of the branches, 5-merous, pedicels ca. 0.5 mm long, terete, covered with spherical glands and glandular trichomes; hypanthia 1‒1.5 × ca. 1 mm, campanulate-oblong, not costate, smooth, green or green-reddish to reddish, sparsely to moderately covered with glandular trichomes; calyx tubes ca. 0.3 mm long; sepals 1.8‒2 × ca. 0.5 mm, triangular, apices acute, glandular, glands inconspicuous and often caducous (ca. 0.2 mm long) longer than the hypanthia length, green or green-reddish to reddish, sparsely to moderately covered with glandular trichomes, glands inconspicuous and often caducous (0.2–0.4 mm long); petals 3.8–4 × 6‒6.5 mm, oblong, apices acute, apiculate (ca. 0.5 mm long) or not, pink, margins entire, glabrous; stamens 10, dimorphic, bicolorous, anthers tetrasporangiate; larger (antesepalous) stamens 5, filaments 2.3–3.3 mm long, pink, pedoconnectives 2.3–3 mm long, pink, ventral appendages 1–1.3 mm long, yellow, apices retuse, anthers 1.8–2 mm long (including beaks), oblong, pink, beaks 0.2–0.4 mm long, pinkish; smaller (antepetalous) stamens 5, filaments 1.5–2 mm long, yellow, pedoconnectives 0.5–0.8 mm long, yellow, ventral appendages inconspicuous ca. 0.1 mm long, yellow, apices retuse, anthers ca. 1.5–1.6 mm long (including beaks), yellow, beaks 0.2–0.3 mm long, yellow; ovaries ca. 1.5 × 1 mm, 3- locular, globose, superior, glabrous; styles ca. 4 mm long, pinkish, slightly curved, stigmas punctiform. Capsules 2–2.5 × 1.8–2 mm, cylindrical or oblong, brownish, smooth, hypanthia totally covering the capsules, peeling off with age, dehiscence basipetal, sepals deciduous in the mature fruits, columellas deciduous; seeds 0.2–0.4 × 0.1–0.2 mm, testa foveolate, slightly curved to one side.

Paratypes:— BRAZIL. Minas Gerais: Belo Horizonte, Parque Estadual da Serra do Rola-Moça, no barranco ao lado direito da estrada para o Morro do Cachimbo , 200 m antes do ponto de ônibus, 20º01’25.0”S 43º59’32.0”W, 1350 m, 27 July 2023, (fl., fr.), A.A. Santos 97 (IBIUEMG!) ; idem, área da COPASA, Morro do Cachimbo, estrada de acesso a Serra do Cachimbo , crescendo em barranco, 31 August 2023, (fl.), M.J.R. Rocha 1451 (IBIUEMG!) ; idem, Morro do Cachimbo, lado esquerdo da estrada, barranco abaixo da primeira torre, 20º00’52”S 43º58’54”W, 1430 m, 13 May 2024, M.J.R. Rocha 1609 (IBIUEMG!). Betim [Nova Lima], slopes of Serra da Mutuca above Barreiros, 1000–1200 m, 03 June 1945, (fl.), L.O. Williams 7285 (F-online image!, K-online image!, NY-online image!, US-online image!) .

Distribution, Habitat, and Conservation: — Microlicia ferricola is found in the Iron Quadrangle in Minas Gerais state. It has been collected only in the Serra do Rola-Moça State Park, which is located in the municipalities of Belo Horizonte, Brumadinho, Ibirité, and Nova Lima ( Fig. 3 ). This lithophyte species frequently occurs at an elevation from 1350 to 1430 meters on slopes in ironstone ecosystems, characterized by shallow, acidic, oligotrophic soils containing high concentrations of metallic minerals, mainly iron (see Carmo et al. 2018). These unique soils develop from iron formations, in this case, ferruginous phyllite [Itabira Group, Cauê Formation] ( Carmo et al. 2018). Microlicia ferricola was collected with flowers and fruits in July and August.

The populations of M. ferricola are exclusively inside a conservation area maintained and managed by the Minas Gerais government ( Fig. 3 ). Despite its restricted AOO and EOO (4 km 2), M. ferricola occurs in a preserved habitat with no disturbances and has populations with a moderate number of individuals. Then, we consider this species as Least Concern (LC) based on IUCN criteria (2022). However, it is imperative to recognize that the surrounding areas adjacent to this protected unit are under significant threat mainly due to extensive mining activities, which has led to a persistent degradation of the quality of the vegetation habitat (see Jacobi et al. 2007). Numerous efforts have been made to draw the attention of relevant authorities to address the mounting biodiversity loss within the Iron Quadrangle, often driven by specific and private interests, but with little success (see Carmo & Kamino 2023).

Etymology: —The specific epithet ferricola is from the Latin words ferreus (= iron) and -cola (= dweller) [see Stearn 1983], referencing the iron-rich soil of the Iron Quadrangle where this new species occurs.

Taxonomic Notes: — Microlicia ferricola shares similarities with three species: M. longicalycina R.Romero in Romero & Castro (2014: 1177), M. trichocalycina De Candolle (1828: 120) , and M. woodgyeriana R.Romero & Paranhos in Romero et al. (2021b: 444). Like M. ferricola , these species are also endemic to Minas Gerais state ( Romero & Castro 2014; Romero et al. 2021 b, 2024). They all have pentamerous flowers with pink petals, bicolored androecium with dimorphic stamens and tetrasporangiate anthers, three-locular ovary, deciduous sepals in the mature fruits, and fruits with basipetal dehiscence and deciduous collumelas. Microlicia ferricola and M. longicalycina also share lanceolate to elliptic-lanceolate leaves with acute apices and entire margins with glandular trichomes. However, M. longicalycina has leaves with light green margins (see Romero & Castro 2014) (vs. entirely green or green-reddish in M. ferricola ) with setose trichomes (vs. only glandular), and long linear-triangular sepals ([4–6 mm long] vs. triangular [1.8‒2 mm long]). Additionally, M. longicalycina is exclusive to the Diamantina municipality and commonly found in the Biribiri State Park ( Romero & Castro 2014). Microlicia ferricola and M. woodgyeriana exhibit elliptic-lanceolate leaves and triangular sepals with entire margins, often with green-reddish to reddish indumentum. But M. woodgyeriana differs by its coriaceous leaves (vs. chartaceous in M. ferricola ), margins that are revolute (vs. flat), and campanulate hypanthia (vs. campanulate-oblong). Microlicia woodgyeriana is endemic to northern Minas Gerais, specifically found in the Serra do Bota municipality of Itacambira ( Romero et al. 2021b). Microlicia ferricola and M. trichocalycina have lanceolate to elliptic-lanceolate leaves with very short petioles. Nevertheless, M. trichocalycina differs in having leaves with non-setose apex (vs. setose in M. ferricola ), hypanthia and sepals moderately to densely covered with long glandular trichomes ([0.5–1 mm long] vs. short [0.2–0.4 mm long]). Microlicia trichocalycina has been recorded by a few collections from Serro municipality in the Diamantina Plateau ( Martius s.n. [M0165724!]), Ouro Preto municipality (Glaziou 14732 [P!], 19319 [P!]), Serra do Gandarela National Park (Emygdio et al. 3375 [NY!], Augsten & Stehmann 628 [BHCB!], Gontijo 1214 [BHCB!], Rocha et al. 1599 [IBIUEMG!]), and Mariana municipality (Brina s.n. [HUFU63159!], Mendes et al. 65 [BHCB!]) in the Iron Quadrangle.

Figures

FIGURE 1. Microlicia ferricola Versiane, M.J.R.Rocha & R.Romero. A. Branches. B. Detailed branch with glandular trichomes. C. Adaxial surface leaf blade. D. Abaxial surface leaf blade. E. Flower. F. Detailed glandular trichomes at hypantium. G. Hypanthium and sepals. H. Petal variation. I. Smaller stamen (antepetalous) on the left, larger stamen (antesepalous) on the right. J. Ovary and style. K. Detailed style apex. L. Ovary showing 3 locules. M. Mature fruit with hypanthium covering. N. Seed. (Drawn by Klei Sousa from Rocha et al. 1437).

FIGURE 2. Microlicia ferricola Versiane, M.J.R.Rocha & R.Romero. Photos of living specimens. A-B. Habitat in the Rola-Moça State Park, Minas Gerais, Brazil. C. Habit of an individual on slope habitat. D. Flowering branch with green leaves. E. Flowering branch with green-reddish to reddish leaves. F. Flower. Photos: M.J.R. Rocha (Rocha 1437 [A, B, E]; Rocha 1451 [C, D]).

FIGURE 3. Occurrence map of Microlicia ferricola Versiane, M.J.R.Rocha & R.Romero at Serra do Rola-Moça State Park, in the Iron Quadrangle, Minas Gerais, Brazil.