Fosterella atlantica Leme, O.B.C. Ribeiro & Forzza, 2019

Leme, Elton M. C., Forzza, Rafaela C., Halbritter, Heidemarie & Ribeiro, Otávio B. C., 2019, Contribution to the study of the genus Fosterella (Bromeliaceae: Pitcairnioideae) in Brazil, Phytotaxa 395 (3), pp. 137-167 : 145-149

publication ID	https://doi.org/ 10.11646/phytotaxa.395.3.1
persistent identifier	https://treatment.plazi.org/id/512CB34B-0910-FA50-CC97-FE075D7547B1
treatment provided by	Felipe
scientific name	Fosterella atlantica Leme, O.B.C. Ribeiro & Forzza
status	sp. nov.

Treatment

1. Fosterella atlantica Leme, O.B.C. Ribeiro & Forzza View in CoL , sp. nov. ( figs. 7 A View FIGURE 7 to G)

Diagnosis:—This new species is similar to F. windischii , differing from it by the entire leaf blades (vs. inconspicuously and subdensely spinulose at the base), primary bracts many times shorter than the stipe of the branches (vs. the basal ones longer than the stipe), inconspicuously white lepidote to glabrescent (vs. densely and coarsely white lepidote), sepals vinaceous toward the apex (vs. greenish), petals vinaceous in the central-apical portion mainly abaxially (vs. white), apex obtuse (vs. acute), forming an apically rounded flower bud before anthesis (vs. flower bud with an acute apex).

Type:— BRAZIL. Minas Gerais: Matutina, Rio Pirapetinga, 830 m elev., 19º13’06.7” S, 45º52’32.6” W, 7 August 2017, E. Leme, O. Ribeiro & R. Oliveira 9223 (holotype RB!, 2 sheets).

Description:— Plants acaulescent, flowering 42–47 cm tall, propagating by basal shoots. Leaves 10–14 in number, fasciculate, subspreading, shorter than to exceeding the peduncle; sheath inconspicuous, subreniform, 1.5–2 × 4–4.5 cm, slightly thickened, corrugated, yellowish toward the base, greenish distally, densely and coarsely white lepidote distally with large adpressed trichomes; blade linear-lanceolate, apex slenderly caudate, slightly narrowed at the base, thin in texture, without any thickened central channel, 20–35 × 1.3–2.6 cm, green, finely nerved, abaxially completely covered by a thick and coarse layer of white, interwoven peltate, shortly fimbriate trichomes (type I), adaxially near the base densely white lepidote with large and coarse adpressed trichomes and glabrous toward the apex, abaxial and adaxial faces strongly contrasting in color, margins entire, undulate. Peduncle erect, 20–26 cm long, 1.5–2.5 mm in diameter, greenish-bronze colored, glabrous; peduncle bracts 8–30 × 2–5 mm, sheathing part ovate to suborbicular contrasting with the narrowly triangular, attenuate blade, slenderly caudate, erect, thin in texture, nerved, entire, inconspicuous white lepidote (basal ones) to glabrescent, longer or the upper ones distinctly shorter than the internodes. Inflorescence shortly paniculate, usually with primary branches and rarely with inconspicuous secondary branches, erect, 16–19 cm long, 6–11 cm in diameter; main axis 1–2 mm in diameter, greenish-bronze colored, glabrous; primary bracts resembling the upper peduncle bracts, filiform-caudate, entire, 3–9 × 1–2 mm, inconspicuously white lepidote to glabrescent, many times shorter than the stipe of the branches; primary branches 8–10 in number, suberect, laxly arranged, 3–8 cm long, 3–13-flowered, the basal ones sometimes bearing secondary branch; secondary bracts resembling the floral bracts, many times shorter than the stipe of the branches; secondary branches ca. 2.5 cm long, ca. 5-flowered; stipe slender, 8–20 × 0.7–1 mm, naked, glabrous; rachis ca. 0.7 mm in diameter, slightly flexuous, green, glabrous; floral bracts suborbicular-triangular, acute, 1.5–2 × 1.5–2 mm, entire, membranaceous, finely nerved, pale vinaceous-castaneous toward the apex, glabrous, slightly shorter than to equaling the pedicel. Flowers 7–8 mm long (with extended petals and including the stamens), 3–7 mm apart, nutant, pedicel 1.5–2.5 mm long, ca. 0.5 mm in diameter, strongly curved downward; sepals broadly ovate to suborbicular, acute, 1.5–2 × 1–1.5 mm, membranaceous, finely nerved, green near the base, vinaceous toward the apex, glabrous; petals narrowly lingulate, obtuse, slightly cucullate, 5–5.5 × 2–2.5 mm, whitish except for the pale wine color of the central-apical portion mainly abaxially, membranaceous, forming a apically rounded flower bud before anthesis, strongly recoiled-recurved at anthesis and afterward, forming a corolla ca. 5.5 mm in diameter; stamens equalling to slightly exceeding the petals; anther narrowly oblong, ca. 2 mm long, basifixed, base bilobed, apex apiculate, strongly spirally recurved at anthesis; pollen oblong-elliptic, sulcate, sulcus broad, without exine elements, margins well defined but not sharply cut, bearing microreticulate exine elements decreasing in size but without any entire marginal area, exine microreticulate, muri narrow; ovary ovoid, ca. 2.5 × 1.5 mm, green; ovules subcylindrical, long caudate; style ca. 4 mm long, white, longer than the ovary and exceeding the petals; stigma simple-erect, white, lobes ca. 0.7 mm long, partially fused at the base, apical margins subentire. Capsules a broadly ovoid to subglobose basket-like structure hanging with the opening downward at dehiscence; seeds narrowly fusiform, bicaudate, ca. 1.5 mm long.

Additional specimen examined (paratype):— BRAZIL. Minas Gerais: Matutina, Rio Pirapetinga, 830 m elev., 19º 13’ 06.7” S, 45º 52’ 32.6” W, 7 August 2017, E. Leme et al. 9224 (RB).

Distribution and habitat:— Fosterella atlantica is known from the type locality only, from the county of Matutina, west of Minas Gerais state, situated in the so called mesoregion of “Triângulo Mineiro-Alto Paranaíba” ( fig. 1 View FIGURE 1 ). It is the first species of Fosterella recorded in Southeastern Brazil, representing the most eastern point of distribution of the genus. The population of this species was originally located and documented by the research team of the Prístino Institute located in Minas Gerais state, Flávio F. do Carmo, Luciana H. Yoshino, and the botanical taxonomist Rubens Custório da Mota, who provided the first field records on this new species.

Fosterella atlantica grows along the river Pirapetinga, in partially shaded sites, as a saxicolous or more often as a terrestrial on clayey soils amidst glauconite rocky outcrops ( figs. 7 A, B, C View FIGURE 7 ), locally known as “verdete”, which is a green colored, potassium sulphate and magnesium sulfate rich rock typical for the region. Flowering was documented in August and September.

Etymology:—The epithet refers to the geographical outlier range of F. atlantica in the southeastern Minas Gerais state, much closer to the Atlantic Ocean than any other species in the genus, which are traditionally known from a western distribution in Central Brazil, not distant from the border with Bolivia and Paraguay, except for a single Amazonian species.

Observations:—The trichome type on the abaxial surface of the leaf blades and petal curvature clearly indicate the closely morphological affinity of F. atlantica to F. windischii . However, the new species differs from it by the entire leaf blades (vs. inconspicuously and subdensely spinulose at the base), inflorescence usually with primary branches and rarely with inconspicuous secondary branches (vs. with distinct secondary branches), primary bracts many times shorter than the stipe of the branches (vs. the basal ones longer than the stipe), inconspicuous white lepidote to glabrescent (vs. densely and coarsely white lepidote), flowers shorter (7–8 mm vs. 7–10 mm long), with shorter pedicel (1.5–2.5 mm vs. 1.5–4 mm long), sepals shorter (1.5–2 × 1–1.5 mm vs. 2–3 × 1.5 mm), vinaceous toward the apex (vs. greenish), petals vinaceous in the central-apical portion mainly abaxially (vs. white), apex obtuse (vs. acute), and forming an apically rounded flower bud before anthesis (vs. flower bud with an acute apex). It is interesting to mention the pollen of this new species has sulcus margins well defined but not sharply cut, bearing microreticulate exine elements decreasing in size, but without any entire marginal area, while in F. windischii pollen has sulcus margins sharply cut and bearing a distinct entire marginal area without microreticulate exine elements.

In addition, F. atlantica has the eastern-most range for the genus, in Minas Gerais state, southeastern Brazil, while F. windischii is known from the western region of Mato Grosso state, central Brazil, close to the border with Bolivia, as well as further western from Bolivia, in the Depto. Santa Cruz, Prov. Velasco ( Ibisch et al. 2008, Peters 2009).

2. Fosterella batistana Ibisch, Leme & J. Peters View in CoL , Selbyana 29: 183. 2008. Type:— BRAZIL. Pará: Itaituba, 400 km on the road from Santarém to Cuiabá, Curuá-una waterfall (west side of Serra do Cachimbo), J. B. Fernandes da Silva s.n., fl. cult. Jan. 2001, E. Leme 5078 (holotype HB!, isotypes FR!, LPB, RB!, SEL!). ( figs. 8 A View FIGURE 8 to D)

Description:— Plants acaulescent, flowering 15–30 cm tall. Leaves ca. 10 in number, subspreading, forming an open rosette; sheath inconspicuous, whitish, glabrous, 1 × 1.8–2 cm, entire; blade narrowly lanceolate, apex long acuminate-caudate, distinctly narrowed toward the base but not petiolate, slightly thickened in texture and canaliculate, thin in texture toward the apex, 18–21 × 3–5 cm, sparsely white lepidote with peltate, dentate trichomes (type III) to glabrescent, light green with pronounced paler colored nerves mainly toward the base and along the margins, margins entire, undulate. Peduncle erect, 6–15 cm long, 1–3 mm in diameter, green, subdensely white lepidote with filamentous trichomes; peduncle bracts the basal ones subfoliaceous, the upper ones narrowly lanceolate, long caudate, erect, longer than the internodes, membranaceous, green, nerved, entire, densely white lepidote abaxially and along the margins. Inflorescence compound-racemose to shortly paniculate, with primary to secondary branches, erect, 6–18 cm long, 3–8 cm in diameter; main axis 2–3 mm in diameter, sparsely white lepidote with filamentous trichomes to glabrescent, green; primary bracts resembling the upper peduncle bracts, entire, 10–25 × 2–3 mm, shorter than to equaling the stipe; primary branches 2–11 in number, suberect, laxly arranged, 2–8.5 cm long, 7–20-flowered, bearing 1–3 secondary branches; stipe slender, 7–20 × 1.5–2 mm, naked or bearing 2–4 bracts with aborted flowers or dormant secondary branches; rachis ca. 1 mm in diameter, straight to slightly flexuous, green, sparsely white lepidote with filamentous trichomes to glabrescent; secondary bracts resembling the upper primary bracts; secondary branches 1–2.5 cm long, 4–10-flowered; floral bracts ovate-lanceolate, acuminate, 2–3 × 1 mm, entire, membranaceous, green to stramineous, nerved, inconspicuously and sparsely white lepidote with filamentous trichomes, about equaling the pedicel. Flowers 7–9 mm long (with extended petals), 3–7 mm apart, subsecund; pedicel 1–3 mm long, ca. 0.5 mm in diameter, curved downward; sepals ovate, acute, ca. 2 × 0.7 mm, green, glabrous; petals narrowly suboblong-ovate, subacute to narrowly obtuse, ca. 6 × 2 mm, whitish, strongly recurved at anthesis but not recoiled, somewhat straight afterwards; stamens distinctly shorter than the petals, but completely exposed at anthesis; anther sublinear, ca. 2 mm long, dorsifixed near the base, base bilobed, apex apiculate, distinctly recurved at anthesis; pollen broadly ellipsoidal, sulcate, sulcus broad, without exine elements, margins well defined to sharply cut, with an irregular, narrow to broad entire marginal area without microreticulate exine elements, exine microreticulate; style ca. 3 mm long; stigma simple-erect with tendency to conduplicate, lobes enlarged from base to apex, recurved, margins crenulate; ovary ellipsoidal; ovules subcylindrical, obtuse. Capsules ovoid, ca. 3 × 2 mm; seeds filiform, bicaudate, ca. 2 mm long.

Additional specimen examined:— BRAZIL. Pará: Jacareacanga, Rio das Tropas, afluente da margem direita do Rio Tapajós, epífita da floresta aluvial, J.B. Fernandes da Silva s.n., cult. E. Leme 7696 (RB). Amazonas, Coari, Rio Urucu, base de produção de Petróleo, s.d., J.B. Fernandes da Silva 1227 (IAN).

Distribution and habitat: — According to the collector, F. batistana was found growing as a saxicole in a very humid site, near Curuá-una waterfall, in the middle of the Amazon forest. The place of collection is about 400 km from the city of Santarém, which is situated in the confluence of Tapajós and Amazonas rivers, not far from the border with the State of Amazonas. There is a specimen deposited in IAN herbarium (J.B. Fernandes da Silva 1227) indicating a collection from the region of Rio Urucu, Coari, Amazonas state. However, according to the collector, the indicated origin is probably a labeling mistake, since as far as his memory is concerned, he left a living specimen of Fosterella then with the IAC curator, but it was really collected in Serra do Cachimbo, situated south of Pará state on the border with Mato Grosso State.

The very humid habitat of this new species may explain its very delicate leaf texture, which is thinly subchartaceous to submembranaceous toward the apex.

An additional specimen collected in Jacareacanga, Pará state, has an unusual epiphytic habit (João Batista Fernandes da Silva, pers. com.) for the first time reported for the genus, which is possibly an adaptation to periodically floaded sites in Igarapé forest in the Amazon region.

Etymology:— The epithet of this species honors the collector of the type specimen, the Amazonian orchid specialist, João Batista Fernandes da Silva, who has discovered countless new species.

Observations:— Fosterella batistana can be distinguished from all Brazilian species by the combination of its geographical range restricted to Amazonian region, its small stature, flowering 15–30 cm tall, the broad leaf blades 3–5 cm wide, which are distinctly narrowed toward the base but not petionate, glabrescent or sparsely covered by peltate, dentate, white trichomes of the type III, inflorescence axis and floral bracts sparsely lepidote with filamentous trichomes.

In the protologue, Peters et al. (2008b) pointed towards the close morphological affinity of F. batistana to the Andean F. weberbaueri (Mez) L.B. Smith (1960: 172) , known from Bolivia and Peru, which shares the same type of leaf trichomes. The close relationship and distinctness as well, is corroborated by molecular data based on four chloroplast DNA regions ( Rex et al. 2009). Besides its clearly distinct geographical range, F. batistana differs from F. weberbaueri by its acaulescent habit (vs. subcaulescent), smaller stature when in bloom (15–30 cm vs. to 90 cm tall), leaf blades sparsely lepidote to glabrescent (vs. glabrous adaxially only), and by the shorter inflorescence (6–18 cm vs. 25–30 cm long), which is sparsely white lepidote (vs. glabrescent).