Microlicia gracilis Fontelas & R.Romero, 2020

Fontelas, Jean Correa & Romero, Rosana, 2020, Two new species of Microlicia D. Don (Melastomataceae, Microlicieae) from Chapada dos Veadeiros, Goias State, Brazil, PhytoKeys 164, pp. 115-126 : 115

Microlicia gracilis Fontelas & R.Romero sp. nov. Fig. 1

Type.

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]).

Diagnosis.

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.

Description.

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.

Distribution and habitat.

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. 2 ).

Conservation status.

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 ( IUCN 2019), is preliminarily assessed as Critically Endangered [CR B1ab (iii) + 2ab (iii)]. So far, collections of M. gracilis have been made only outside the boundaries of the Chapada dos Veadeiros National Park and, therefore, it is not protected by any conservation units. The restricted distribution of M. gracilis also contributes to its degree of threat, since its populations are exposed to frequent burning caused by farmers, in addition to the expansion of agricultural borders in the region ( Felfili et al. 2007; Alves et al. 2013).

Phenology.

Flowers have been collected in March, May and June and fruits in May and June.

Etymology.

The specific epithet " gracilis " refers to the very delicate and fragile branches and leaves and the small size of the flowers.

Additional specimens examined

(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]).

Figures

Figure 1. Microlicia gracilis Fontelas & R. Romero A flowering branch B leaf adaxial surface C flower bud D detail of the flower bud E petal F larger (antesepalous) stamen G smaller (antepetalous) stamen H gynoecium I closed capsule (A-I: C. Munhoz et al. 1519). Photos: Jean Fontelas.

Figure 2. Geographical distribution of Microlicia gracilis and M. xylopodifera in the state of Goias, Brazil.