Ameroglossum bicolor E.M.Almeida, A.M.Wanderley & L.P.Felix, 2021

Almeida, Erton M., Christenhusz, Maarten J. M., Wanderley, Artur Maia, Cordeiro, Joel Maciel P., Melo, José Iranildo Miranda De, Batista, Fabiane Rabelo Da Costa & Felix, Leonardo P., 2021, An overview of the Brazilian inselberg genus Ameroglossum (Linderniaceae, Lamiales), with the description of seven new species, European Journal of Taxonomy 746, pp. 1-25 : 11-13

Ameroglossum bicolor E.M.Almeida, A.M.Wanderley & L.P.Felix sp. nov.

urn:lsid:ipni.org:names:77216327-1

Figs 2C , 4a–c

Diagnosis

This species is morphologically similar to A. alatum sp. nov. in having lustrous branches and leaves, winged pedicels, and white trichomes on the lower lip of the corolla tube. It differs in having green or slightly purplish vegetative portions (vs completely green), wings not evident (vs strongly winged), inflorescence usually a compound dichasium (vs simple dichasium) and the dorsal sepal partially covering the lateral sepals (vs the sepals not overlapping).

Etymology

The specific epithet is the Latin adjective ʻ bicolor ʼ, ʻtwo-coloredʼ, referring to the vegetative variation observed in its populations. Among the four populations described here, it was possible to encounter green or purplish, almost wine-coloured, plants in the same population, a characteristic only observed in this species.

Material examined

Type BRAZIL – Pernambuco • Agrestina, Lajedo do Boi ; 08°28ʹ08ʺ S, 35°55ʹ06ʺ W; 428 m a.s.l.; 21 Aug. 2014; E.M. Almeida, E.M. Almeida & M. Fernandes 1229; holotype: EAN!; isotypes: IPA!, K!, RB!, UFP!.

Paratypes BRAZIL – Pernambuco • Caruaru, Pedra do Guariba ; 29 Jul. 2005; Y. Melo, M. Alves, P. Santos, A. Araújo, J. Rodrigues, J. Gomes, S. Martins & B. Maciel 43; UFP[41,995] ! • Pedra do Guariba ; 08°22ʹ55ʺ S, 35°50ʹ38ʺ W; 685 m a.s.l.; 22 Jul. 2007; M. Sobral-Leite, B. Maciel & P. Gomes 359; UFP[46,440] ! • “ Pedra do Guariba ”; 08°22ʹ55ʺ S, 35°50ʹ38ʺ W; 685 m a.s.l.; 22 Jul. 2007; M. Sobral- Leite, B. Maciel & P. Gomes 382; IPA[80,821] ! • Divisa entre os municípios de Caruaru e Agrestina, Serra da Quitéria , Sítio flexeira , “ Pedra do Urubu ”; 08°23ʹ43ʺ S, 35°59ʹ33ʺ W; 540 m a.s.l.; 24 Jul. 2009; M. Sobral-Leite, B. Maciel & P. Gomes 916; UFP[57,163] ! • “ Pedra do Urubu ”; 08°23ʹ43ʺ S, 35°59ʹ33ʺ W; 540 m a.s.l.; 24 Jul. 2009; M. Sobral-Leite, B. Maciel & P. Gomes 916; IPA[83,689] ! • Agrestina , Distrito de Terra Vermelha, Pedra do Urubu ; ca 700 m a.s.l.; 2 Aug. 2009; A.M.Wanderley 1; UFP[58,598] !• Bonito ; 08°29ʹ10ʺ S, 35°43ʹ42ʺ W; 446 m a.s.l.; 3 Jul. 2015; L.P. Felix, E.M. Almeida & J.P. Araújo 15758; EAN[22,895] ! • Quipapá; 12 Mar. 1958; Dárdano de Andrade-Lima 50-600; IPA !.

Description

Saxicolous chamaephyte up to 80 cm, with frequent secondary branching along the stem.Young branches purplish or greenish, lustrous, quadrangular, not winged, glabrescent, trichomes aciculate and papillose, principally near the insertion of the young leaves; branches brownish when mature, slightly inclined to incumbent, subquadrangular. Leaves opposite, decussate; leaf blade 3.4–9.1 × 1.0– 3.8 cm, green and tinged with purple when young, bullate, later green to greenish, smooth, lustrous, elliptic, rarely narrowly elliptic; adaxial side glabrous; abaxial side glabrescent, trichomes recurved and/or papillose; apex acute, rarely acuminate, flat; margin flat, occasionally revolute, ciliate. Inflorescence a compound dichasium, occasionally simple. Peduncle green or slightly purplish, subcylindrical, winged to the median third, glabrescent, with papillose trichomes; primary peduncle 0.9–3.0 × 0.1–0.2 cm, secondary peduncle 0.45–1.40 × 0.06–0.15 cm, tertiary peduncle 0.36–0.80 × 0.06–0.09 cm. Pedicel 0.6–1.3 × 0.06–0.10 cm, green or tinged purple, ventral portion not winged, glabrous. Bracts 0.20–0.60 × 0.05– 0.10 cm, green or tinged purple, glabrescent, with papillose trichomes, margin glabrous. Calyx greenish to slightly purplish, abaxial side glabrescent, with trichomes papillose, rarely aciculate, adaxial side densely covered by papillose trichomes, margin glabrous; dorsal sepal 1.5–2.1 × 0.5–0.7 cm, broadly lanceolate to ovate, partially covering the lateral sepals; lateral sepals 1.2–1.6 × 0.2–0.3 cm, lanceolate; ventral ones 1.5–1.3 × 0.3–0.4 cm, lanceolate. Corolla 4.4–5.2 cm long, yellow-orange or scarlet, externally pubescent, with trichomes glandular and/or papillose, internally glabrous; tube 3.2–4.0 cm long; upper lip 1.2–1.4 × 0.8–0.9 cm, slightly bilobate; lower lip 0.9–1.3 × 0.4–0.5 cm, inner perianth with trichomes filiform, white; lobes revolute, median lobe 0.13–0.15 × 0.06–0.07 cm. Ventral pair of stamens sometimes exserted, adnate until the median third of the corolla tube; filaments violet, dorsal ones 1.70–2.40 × 0.08 cm, ventral ones 2.00–2.50 × 0.08 cm; thecae 0.15 cm diam.; staminodium 0.5– 1.1 cm, adnate until the middle third of the corolla tube, glabrous. Ovary 0.5 × 0.2 cm; style 4.0– 5.5 cm, sometimes exserted, glabrous. Capsule 1.5–1.7 × 0.7–1.0 cm, green or tinged purple. Seeds 0.10 × 0.04 cm.

Distribution

Three populations of Ameroglossum bicolor sp. nov. are known from granite outcrops in the municipalities of Agrestina, Bonito and Caruaru in the Agreste mesoregion of Pernambuco State, Brazil. It grows at elevations between 425 and 700 m.

Ecology

Ameroglossum bicolor sp. nov. has been collected in flower from May to October, with high inter- and intrapopulational synchrony ( Wanderley et al. 2014a).

Population and threats

A population of 70 adult individuals is known from a granite outcrop known as Lajedo do Boi in the municipality of Agrestina; at least 40 individuals are known from the Pedra do Guariba granite outcrop in the municipality of Caruaru ( Wanderley et al. 2014a); four other individuals were also located in Caruaru at Serra da Quitéria; 50 adult individuals are estimated to compose the population in the municipality of Bonito, all in Pernambuco State, Brazil. Main threats to these populations are habitat destruction through trampling by domestic animals, burning and other agricultural activity.

Figures

Fig. 2. Reproductive branches and floral details of different taxa of the genus Ameroglossum Eb.Fisch., S.Vogel & A.V.Lopes. A. A. alatum sp. nov. B. A. asperifolium sp. nov. C. A. bicolor sp. nov. D. A. fulniorum sp. nov. E. A. genaroanum sp. nov. F. A. intermedium sp. nov. G. A. manoelfelixii L.P.Felix & E.M.Almeida. H. A. pernambucense Eb.Fisch., S.Vogel & A.V.Lopes. I. A. xukuruorum sp. nov.

Fig. 4. a–c. Ameroglossum bicolor sp. nov. (Almeida et al. 1229). a. Reproductive branches. b. Flower. c. Corolla opened, showing the stamens. d–g. Ameroglossum fulniorum sp. nov. (Almeida & Wanderley 439). d. Reproductive branches. e. Leaf, adaxial side. f. Flower. g. Corolla opened, showing the stamens.