Aciotis acuminifolia (Martius ex De Candolle 1828: 116 ) Triana (1871: 51)

Corrêa, André Luis, Scudeller, Veridiana Vizoni & Goldenberg, Renato, 2017, Melastomataceae in the Reserva de Desenvolvimento Sustentável do Tupé, Amazonas, Brazil, Phytotaxa 323 (2), pp. 101-127 : 106

1. Aciotis acuminifolia (Martius ex De Candolle 1828: 116) Triana (1871: 51) . ( Figure 3 P .)

Herbs ca. 30 cm tall. Green smooth rhytidome. Branches erect or prostrate, cylindrical, not winged, reddish; branches, petiole, leaf, inflorescence, bracts, bracteole, hypanthium and fruit with glandular caducous trichomes. Leaves opposite isophyllous; petioles channelled 1–2.2 mm long; leaf blades 2.1–4.7 × 1.4–3.4 cm, membranous, concolorous, symmetrical, elliptical or oval-shaped, base attenuate or cuneate, apex acute or acuminate, margins serrate and ciliate, adaxial side glabrous, abaxial surface with glandular caducous trichomes, leaf veins 3 or 5, suprabasal; ant domatia absent. Cyme 2.7–5.3 × 2–5.1 cm, terminal; bracts 1.1–2.1 mm long, oval-shaped persistent, with persistent glandular trichomes; bracteoles 0.3–0.7 mm long. Flowers 4-merous; pedicels 0.2–0.5 mm long; hypanthium ca. 1.4 mm long, campanulate, smooth; calyx simple, persistent; petals 3.5– 1.2 mm, white, obovate, symmetrical, apex acute, base attenuate, margins entire, glabrous; stamens 8, isomorphic, anthers 1.1–1.7 mm long, pinkish, oblong, straight, apex attenuate, 1 apical pore, connective not prolonged, filament 2.5–2.8 mm long, glabrous; ovary ca. 2.3 mm long, half-inferior, placentation axillary, 2-locular, glabrous; style ca. 6.1 mm long, straight, glabrous. Capsule 2.7–3.6 × 2.2–3.1 mm, unripe fruit green, ripe fruit red; seeds numerous, ovoid.

Specimens examined: — BRAZIL. Amazonas : Manaus, RDS-Tupé, 02 November 2012, fl.,fr., A. L. Corrêa 102 ( EAFM!, HUAM!, INPA!) ; 05 December 2012, fl.fr., A. L. Corrêa 111 ( EAFM!, HUAM!, INPA!) .

Distribution and habitat: — Colombia, Ecuador, Peru, Bolivia, Venezuela, Guyana, Suriname ( Freire-Fierro, 2002). In Brazil it occurs in Amazonian forests, Cerrado and Atlantic florest ( Rosa & Baumgratz, 2015). In the reserve it occurs in “igapó” or along streams, and in open environments on sandy soil.

Comments: —This species is common in the reserve, forming large populations. It is similar to Aciotis indecora (Bonpland) Triana , because of the herbaceous habit and reddish branches, but it differs by the glabrous ovary.

Figures

FIGURE 3. Morphological details of Melastomataceae species in RDS-Tupé: A. Adelobotrys marginata, leaf blade (from Corrêa 278); B. Miconia comptifolia, leaf blade with detail of the margins (from Corrêa 219); C. Tococa subciliata, leaf blade with detail of the margins (from Corrêa 112); D. Clidemia epibaterium, leaf blade with of the detail margins (from Corrêa 215); E. C. heteroneura, leaf base (from Corrêa 140); F. C. japurensis, leaf base (from Corrêa 21); G. Henriettea maroniensis, leaf blade and detail of trichomes on the abaxial surface (from Corrêa 139); H. M. poeppigii, leaf blade and detail of trichomes on the abaxial surface (from Corrêa 280); I. M. umbrosa, leaf base and detail of trichomes on the abaxial surface (from Corrêa 81); J. Tibouchina fothergillae, longitudinal section of the ovary, hypathium and calix (from Corrêa 218); K. M. umbrosa, detail of the ovary and style (from Corrêa 81); L. M. gratissima, transverse section of the ovary (from Corrêa 137); M. Aciotis circaeifolia, petal (from Corrêa,21);N. C. epibaterium, petal (from Ribeiro 932); O. Miconia tomentosa, stamen larger (from Corrêa 47); P. Aciotis acuminifolia, fruit (From Corrêa 102); Q. M. rubiginosa, fruit (from Scudeller 1067); R. Miconia phanerostila, seed (from Herb 96); S. M. lourteigiana, arachnoid trichome (from Corrêa 77I); T. M. crassinervia, dendritic trichome (from Corrêa 248) U. M. poeppigii, stellate trichome (from Corrêa 280); V. Adelobotrys marginata, malpighiaceous tricome (from Corrêa 278).