Research Article |
Corresponding author: Jean Correa Fontelas ( fontelas@ufu.br ) Academic editor: Ricardo Kriebel
© 2020 Jean Correa Fontelas, Rosana Romero.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Fontelas JC, Romero R (2020) Two new species of Microlicia D.Don (Melastomataceae, Microlicieae) from Chapada dos Veadeiros, Goiás State, Brazil. PhytoKeys 164: 115-126. https://doi.org/10.3897/phytokeys.164.57569
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Microlicia gracilis and Microlicia xylopodifera, endemic to Chapada dos Veadeiros, Goiás State, Brazil, are described, illustrated and the conservation status is also provided. Both species resemble Microlicia ordinata and Microlicia ramosa that are also endemic to Goiás, by having sessile leaf with serrate and ciliate margin, pedicellate flower, triangular and short sepal and dimorphic stamens with bicolorous and polysporangiate anthers. However, M. gracilis differs by the long internode (2–4 mm long), concolorous, semi-amplexicaul and lanceolate leaf, and petal acuminate at the apex. Microlicia xylopodifera differs in having a robust xylopodium, horizontal or slightly ascending leaf and a dense crown of glandular trichomes at the apex of flower bud.
Microlicia gracilis e Microlicia xylopodifera, endêmicas da Chapada dos Veadeiros, são descritas, ilustradas e o estado de conservação fornecido. Ambas espécies se assemelham à Microlicia ordinata e Microlicia ramosa, também endêmicas de Goiás, por apresentarem folha séssil, com margem serreado-ciliada, flor pedicelada, sépala triangular, curta e estames dimórficos com anteras bicolores e poliesporangiadas. Contudo, M. gracilis diferencia-se pelo entrenó longo (2–4 m compr.), folha concolor, lanceolada e semiamplexicaule, e pétala acuminada no ápice. Microlicia xylopodifera difere por apresentar xilopódio robusto, folha horizontal ou levemente ascendente e uma coroa densa de tricomas glandulares no ápice do botão floral.
Cerrado rupestre, endemism, Microlicieae, taxonomy
Microlicia D.Don is a Brazilian genus with 166 species exclusive to Brazil (
The Chapada dos Veadeiros, located in the north-eastern part of the State of Goiás, is considered an important floristic component of the Cerrado biome with different phytophysiognomies at elevations that vary from 800 to 1650 metres (
Microlicia has been traditionally characterised in having solitary flowers with five, rarely six petals, free ovary with three or five locules and capsules with longitudinal dehiscence from the apex to the base (
In the course of preparing a taxonomic treatment of Microlicieae for the State of Goiás, some collections from Chapada dos Veadeiros could not be recognised under any name in the genus and so we concluded that these collections refer to two new undescribed species. The new species are described, compared morphologically with similar species and information about geographic distribution and conservation status is provided, as well as images of morphological structures of the two species.
This study was based on the morphological analysis of specimens of Microlicia from the following herbaria: HEPH, HUFU, IBGE, MBM, MO, NY, UB, UEC and US (acronyms according to
Brazil. Goiás: Alto Paraíso de Goiás, Fazenda Água Fria, ca. 10 km em direção a Teresina de Goiás, 1448 m elev., 14°04'21.7"S, 47°30'33.6"W, 27 March 2001 (fl, fr), C. Munhoz et al. 2649 (holotype: IBGE! [IBGE00050788]; isotypes: HUFU!, MO! [MO-2024291]).
The new species can be recognised by the long internode (2–4 mm long), lanceolate leaf blade, attenuate and semi-amplexicaul at the base, conspicuous calyx tube (0.2 mm long) and petal acuminate at the apex.
Subshrub, 0.4–0.6 m tall, erect, much-branched. Stem terete, glabrous, decorticating with age. Branch fastigiate, younger branch green, quadrangular, older branch brownish, becoming terete, glabrescent and leafless with age. Branch, both surfaces of the leaf, hypanthium and sepal covered by spherical glands and setose trichomes 0.2–0.4 mm long. Leaf sessile, horizontal or ascending, lax, internode 2–4 mm long; blade 2–3 × 0.5–1 mm, concolorous, green, chartaceous, lanceolate, acute at the apex, with a terminal setose trichome ca. 0.2 mm long, base attenuate, semi-amplexicaul, margin flat, serrate, ciliate, 3-veined, usually inconspicuous on abaxial surface. Flower 5-merous, solitary, terminal or lateral, perianth actinomorphic; pedicel ca. 0.5 mm long; hypanthium 2.5–3 × 1–1.5 mm, purple or green with purple stains, urceolate, calyx tube ca. 0.2 mm long, sepal 0.5–1 × 3.5–5 mm, shorter than the length of the hypanthium, triangular, acute at the apex, with a terminal setose trichome ca. 0.2 mm long; petal 4–4.5 × 3–3.5 mm, magenta, obovate, acuminate at the apex, margin entire, glabrous; stamen 10, dimorphic, anther polysporangiate; larger (antesepalous) stamen 5, filament 2–2.5 mm long, magenta, pedoconnective 2–2.5 mm long, magenta, ventral appendage ca. 1 mm long, yellow, obtuse at the apex, anther ca. 1.8 mm long including beak, vinaceous, ovate-oblong, beak ca. 0.5 mm long; smaller (antepetalous) stamen 5, filament 2–2.5 mm long, magenta, pedoconnective 0.5–1 mm long, yellow, ventral appendage ca. 0.2 mm long, yellow, rounded at the apex, anther ca. 1.5 mm long including beak, yellow, ovate-oblong, beak ca. 0.3 mm long; ovary ca. 1.5 × 1 mm, 3-locular, pyriform, superior, glabrous; style ca. 3 mm long, magenta, terete, slightly curved; stigma punctiform. Capsule ca. 2 × 2 mm, brownish, globose, dehiscing into 3 valves from the apex, hypanthium partially covering the capsule; seed ca. 0.5 × 0.3 mm, brown, oblong, testa foveolate.
Microlicia gracilis is endemic to Chapada dos Veadeiros, Goiás, Brazil, occurring in wet grasslands close to rocky outcrops and in cerrado rupestre, between 1115 m and 1448 m elevation (Fig.
Microlicia gracilis has a restricted extent of occurrence (EOO = 10 km2) and area of occupancy (AOO = 8 km2) and, according to the IUCN Categories and Criteria (
Flowers have been collected in March, May and June and fruits in May and June.
The specific epithet “gracilis” refers to the very delicate and fragile branches and leaves and the small size of the flowers.
(paratypes). Brazil. Goiás: Alto Paraíso de Goiás, Fazenda Água Fria, 14°4'21"S, 47°30'33"W, 1 May 1998 (fl, fr), R.C. Oliveira et al. 1059 (HEPH! [HEPH00020094], MBM!, UB! [UB-0110744]); Chapada dos Veadeiros, ca. 11 km da cidade, 1115 m elev., 14°09'68.5"S, 47°36'37.0"W, 16 June 1998 (fl, fr), R. Romero et al. 5522 (HUFU!, UEC!); Fazenda Água Fria, ca. 10 km em direção à Teresina de Goiás, 1448 m elev., 14°04'21.7"S, 47°30'33.6"W, 3 June 2000 (fl, fr), C. Munhoz et al. 1519 (HUFU!, MO! [MO-2024287]).
Brazil. Goiás: Alto Paraíso de Goiás, ca. 40 km N, 1250 m elev., 24 March 1971 (fl, fr), H.S. Irwin et al. 33108 (holotype: UEC!, isotypes: CAS! [CAS0519655], NY!, US! [US-01899836]).
The new species can be recognised by the robust xylopodium, cespitose habit, indumentum of spherical glands, setose and glandular trichomes on branch, leaf, hypanthium and sepal and flower bud with a dense crown of glandular trichomes at the apex.
Subshrub, 0.1–0.2 m tall, cespitose, robust xylopodium present. Stem terete, glabrous. Branch fastigiate, younger branch green, quadrangular, older branch brownish, becoming terete, glabrescent and leafless with age. Branch, both surfaces of the leaf, hypanthium and sepal covered by spherical glands, setose and glandular trichomes 0.2–1.5 mm long. Leaf sessile, horizontal or ascending, lax, internode 2–6 mm long; blade 2.5–9 × 1.5–5.5 mm, discolorous, adaxial surface darker than the abaxial surface (in dry state), chartaceous, ovate or ovate-lanceolate, acute at the apex, with a terminal glandular trichome, 0.5–1 mm, base rounded or slightly cordate, margin flat, serrate, ciliate, 3-veined, usually inconspicuous on both surfaces. Flower 5-merous, solitary, terminal or lateral, perianth actinomorphic; pedicel 0.7–1 mm long; hypanthium 3.5–4.5 × 1.5–2 mm, green, urceolate; calyx tube ca. 0.2 mm long; sepal 1–2 × 1–1.5 mm, triangular, acute at the apex, with a terminal glandular trichome ca. 0.5 mm long; petal 5–10 × 2.5–5 mm, pink, obovate, obovate-oblong or oblong, acute at the apex, flower bud with a crown of glandular trichomes, during anthesis, the trichomes are only at the apex, margin entire; stamen 10, dimorphic, anther polysporangiate; larger (antesepalous) stamen 5, filament 2.5–3.5 mm long, pinkish, sometimes yellow, pedoconnective 2–3 mm long, pinkish, sometimes yellow; ventral appendage 1.5–2 mm long, yellow, truncate or rounded at the apex, rarely obtuse, anther 1.5–2 mm long including beak, vinaceous, ovate-oblong, beak 0.3–0.5 mm long; smaller (antepetalous) stamen 5, filament ca. 3 mm long, pinkish, sometimes yellow, pedoconnective ca. 1 mm long, pinkish, sometimes yellow, ventral appendage ca. 0.3 mm long, yellow, acute at the apex, anther ca. 1.5 mm long including beak, yellow, ovate-oblong, beak 0.3–0.5 mm long; ovary ca. 2.5 × 1.5 mm, 3-locular, pyriform, superior, glabrous; style ca. 6 mm long, pinkish, terete, slightly curved at the apex; stigma punctiform. Capsule ca. 2 × 2 mm, brown, globose, dehiscing into 3 valves from the apex, hypanthium partially covering the capsule; seed ca. 0.6 × 0.3 mm, brown, oblong, testa foveolate.
Microlicia xylopodifera Fontelas & R.Romero A habit, showing a xylopodium B leaf adaxial surface C flower bud D detail of the apex of the flower bud with a crown of glandular trichomes E petal F larger (antesepalous) stamen G smaller (antepetalous) stamen H gynoecium I closed capsule (A–I: H.S. Irwin et al. 33108). Photos: Jean Fontelas.
Microlicia xylopodifera is endemic to Chapada dos Veadeiros, Goiás State, Brazil, occurring in cerrado rupestre and campo limpo, on sandy soil, between 1000 m and 1800 m elevation (Fig.
Microlicia xylopodifera has a restricted extent of occurrence (EOO = 80 km2) and area of occupancy (AOO = 20 km2) and, therefore, we recommend that it be considered Endangered [EN B1ab (ii, iii, iv] if all
Flowers and fruits have been collected in March.
The specific epithet “xylopodifera” refers to the robust xylopodium (also described as lignotubers) present in all specimens examined. Xylopodium or lignotuber is an organ that buffers the plant against extremes of water loss, temporal mineral or nutritional deficiency, providing also protection against fire (
(paratypes). Brazil. Goiás: Alto Paraíso de Goiás, ca. 30 km ao norte da Chapada dos Veadeiros, 1000 m elev., 16 March 1969 (fl), H.S. Irwin et al. 24490 (NY!); ca. 19 km N, 1250 m elev., 20 March 1971 (fl), H.S. Irwin et al. 32788 (NY!, UEC!, US!); 8 km N, 1500 m elev., 6 March 1973 (fl), W.R. Anderson 6433 (NY!, US!); ca. 29 km N, 800 m elev., 9 March 1973 (fl), W.R. Anderson 6742 (NY!, US!). Teresina de Goiás, 31 km na estrada ao sul para Alto Paraíso de Goiás, 1500 m elev., 16 March 1973 (fl), W.R. Anderson 7162 (NY!, US!).
Using the key to the species of Microlicia of the Chapada dos Veadeiros National Park proposed by
Comparative features of Microlicia gracilis, M. xylopodifera and relatives.
Characters | M. gracilis | M. ordinata | M. ramosa | M. vestita | M. xylopodifera |
---|---|---|---|---|---|
Indumentum of branch, leaf, hypanthium and sepal | Setose trichomes and spherical glands | Glandular trichomes and spherical glands | Setose trichomes and spherical glands | Setose trichomes and spherical glands | Setose, glandular trichomes and spherical glands |
Leaf colour | Concolorous | Discolorous | Discolorous | Concolorous | Discolorous |
Leaf base | Attenuate | Rounded or cordate | Slightly cordate, rarely rounded | Rounded or slightly cordate | Rounded or cordate |
Petal apex | Acuminate | Retuse or truncate | Acute | Acute | Acute |
Petal indumentum | Glabrous | Single glandular trichome at the apex | Glabrous | Single setose trichome at the apex | Glandular trichomes at the apex |
Anther colours | Vinaceous and yellow | Yellow | Vinaceous and yellow | Yellow | Vinaceous and yellow |
Anther, numbers of sporangia | Polysporangiate | Polysporangiate | Polysporangiate | Tetrasporangiate | Polysporangiate |
References HUEG, HUFU, K, MBM, NY, UB, UEC | C. Munhoz et al. 2649 (HUFU) | G. & M. Hatschbach et al. 60297 (HUFU, MBM) | J.N. Nakajima et al. 5049 (UEC, HUEG, HUFU, K, MBM, UB) | M.L. Fonseca et al. 105 (HUFU, IBGE) | H.S. Irwin et al. 33108 (UEC, NY) |
Microlicia gracilis bears some resemblance to Microlicia xylopodifera in having sessile leaf with a lax arrangement on the branches, pedicellate flower (pedicel 0.7–1 mm long), urceolate hypanthium, dimorphic stamens with bicolorous and polysporangiate anthers. However, M. xylopodifera differs in having a cespitose habit, robust xylopodium and glandular trichomes covering branch, both leaf blade surfaces, hypanthium and sepal. Moreover, the apex of the flower bud is densely hairy-glandular, forming a crown at its apex and, during anthesis, the trichomes are concentrated at the apex of the petal. Microlicia gracilis resembles Microlicia ramosa Pilger, which is endemic to Goiás (
Microlicia xylopodifera is distinguished from other species of Microlicia by the presence of a robust xylopodium and a crown of glandular trichomes at the apex of the flower bud, which are concentrated at the apex of the petal. The new species is similar to M. ramosa Pilger in having sessile, discolorous and ovate or ovate-lanceolate leaves that are rounded or slightly cordate at the base, pedicellate flower, triangular sepal and dimorphic stamens with bicolorous, polysporangiate and ovate-oblong anthers. However, M. ramosa differs in having shorter secondary branches, 3–5-veined leaf and a vinaceous or greenish hypanthium often with vinaceous stains. Microlicia xylopodifera also resembles M. ordinata (Wurdack) Almeda & A.B.Martins, which is endemic to Goiás (
The authors are grateful to curators and staff of HEPH, HUFU, MO, MBM, NY, UB, UEC and US herbaria for loan of specimens, to Daniela Ramalho (HEPH), Marina Fonseca (IBGE) and Jim Solomon (MO) for sending images of the isotypes, to Pró-Reitoria de Pesquisa e Pós-Graduação, Universidade Federal de Uberlândia (PROPP/UFU) for financial support and facilities for the field expedition and to Cynthia Sothers for the English revision; to Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG, process APQ 01911–16) for supporting research on Melastomataceae. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001.