Ameroglossum genaroanum E.M.Almeida, J.M.P.Cordeiro & 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 : 14-16

Ameroglossum genaroanum E.M.Almeida, J.M.P.Cordeiro & L.P.Felix sp. nov.

urn:lsid:ipni.org:names:77216329-1

Figa 2E, 5a–d

Diagnosis

This species is morphologically similar to A. manoelfelixii in having young leaves with revolute margins, vegetative structures lustrous and violet trichomes on the lower lip of the corolla tube. It differs from that species in its green vegetative portions (vs tinged purple), leaf blade elliptic to ovate (vs elliptic to narrowly elliptic, sometimes trullate) and flowers orangish (vs scarlet).

Etymology

The specific name is in honour of Prof. Genaro Viana Dornelas, a senior professor at the Universidade Federal da Paraíba, who has a vast knowledge of the flora of Paraíba State.

Material examined

Type BRAZIL – Paraíba • Tacima, Sítio Pão de Açúcar ; 06°35′33″S, 35°27′38″W; 198 m a.s.l.; 28 Jul. 2012; E.M. Almeida, E.M. Almeida & S.L.M. Almeida 397; holotype: EAN!; isotypes: IPA!, K!, RB!, UFP !.

Paratypes BRAZIL – Paraíba • Serra da Raiz, Zona Urbana; 06°41ʹ07ʺ S, 35°26ʹ44ʺ W; 341 m a.s.l.; 23 May 2018; L.P. Felix, E.M. Almeida & J.M.P. Cordeiro 17,486; EAN[25,542] !. – Rio Grande do Norte • Santo Antônio, Serra da Micaela ; 06°18ʹ03ʺ S, 35°31ʹ49ʺ W; 295 m a.s.l.; 13 Apr. 2010; L.P. Felix 13041; EAN[16,772] ! • Distrito de Lages , Serrote das Lajes ; 06°20ʹ41ʺ S, 35°27ʹ11ʺ W; 74 m a.s.l.; 17 Aug. 2013; J.L. Costa-Lima 1011; UFP[80,126] ! • Estrada para Goianinha; 06°19ʹ15ʺ S, 35°27ʹ09ʺ W; 102 m a.s.l.; 13 Apr. 2010; L.P. Felix 13044; EAN[13,044] ! Serra da Micaela ; 06°18ʹ03ʺ S, 35°31ʹ49ʺ W; 295 m a.s.l.; 2008; P. A. Porto s.n.; EAN [15972] ! • Serrinha ; 06°16ʹ42ʺ S, 35°29ʹ58ʺ W; 102 m a.s.l.; 16 Apr. 2003; S. Pitrez et al. 365; EAN[10281] !.

Description

Saxicolous chamaephyte up to 100 cm tall, frequently with secondary branching near the tips. Young branches green, lustrous, occasionally bicolor with wide longitudinal purplish stripes, quadrangular, sometimes with a narrow wing, glabrous; brown cinereous when mature, slightly inclined, subquadrangular. Leaves opposite decussate; leaf blade 5.8–11.7× 2.2–4.3 cm, green, lustrous, elliptic to ovate, bullate when young, later smooth; adaxial side glabrous; abaxial side glabrescent, principally the younger leaves, with glandular trichomes; apex acute to acuminate, flat to reflexed; margin flat to revolute, ciliate. Inflorescences simple dichasia, sometimes compound. Peduncle green, cylindrical, without wings, glabrescent, with papillose trichomes; primary peduncle 0.8–2.8 × 0.15 cm, secondary peduncle 0.4–1.1 × 0.1 cm, tertiary peduncle 0.40–0.60 × 0.08 cm. Pedicel 0.4–0.9 × 0.1–0.2 cm, green, glabrescent, with papillose trichomes, ventral side without wings. Bracts 0.20–0.70 × 0.05–0.08 cm, green, abaxial side glabrescent, with aciculate trichomes, adaxial side glabrescent, with papillose and aciculate trichomes, margin glabrous. Calyx green, abaxial side glabrescent, with papillose trichomes, adaxial side densely covered by papillose trichomes, margin ciliate with recurved trichomes; sepals lanceolate, dorsal one 1.1–1.8 × 0.3–0.5 cm, lateral ones 0.8–1.4 × 0.2 cm, ventral ones 0.8–1.4 × 0.2–0.4 cm. Corolla 4.5–5.5 cm long, orangish with yellow base, externally pubescent with glandular trichomes, internally glabrous; tube 3.3–4.2 cm long; upper lip 1.4–1.6 × 0.8–0.9 cm, slightly bilobate; lower lip 0.9–1.3 × 0.4–0.5 cm, inner perianth with filiform trichomes, violet; lobes revolute, median lobe 0.12–0.15 × 0.08–0.10 cm. Stamens included, sometimes with ventral pair exserted, adnate to the middle third of the corolla tube; filaments violet, dorsal ones 1.7–2.3 × 0.7 cm, ventral ones 1.7–2.1 × 0.7 cm; thecae ca 0.2 cm diam.; staminodium 0.3–0.5 cm long, adnate near the proximal third of the corolla tube, glabrescent with short, glandular trichomes. Ovary 0.6–0.8 × 0.2–0.3 cm; style 3.3–4.6 cm long, exserted. Capsule 1.2–1.5 × 0.6–0.8 cm, green. Seeds 0.10 × 0.05 cm.

Distribution

This taxon has a more northerly distribution than the other species of Ameroglossum and occurs the lowest for this genus. It occurs on rock outcrops in the Agreste Paraibano mesoregion, in Paraíba State (two populations), and in the Agreste Potiguar mesoregion in Rio Grande do Norte State (four populations), Brazil. Elevation between 70 and 300 m.

Ecology

Ameroglossum genaroanum sp. nov. occurs on rock outcrops. Flowering and fruiting between April and June.

Population and threats

Ameroglossum genaroanum sp. nov. is represented only by small isolated populations with up to 60 individuals distributed in small geographical areas susceptible to various anthropic impacts.