Bromelia gracilisepala R.F.Monteiro & Forzza, 2015

Monteiro, Raquel Fernandes & Forzza, Rafaela Campostrini, 2015, Bromelia gracilisepala (Bromeliaceae), a new species from the northwestern frontier of Brazil, Phytotaxa 205 (2), pp. 111-111 : 111

Bromelia gracilisepala R.F.Monteiro & Forzza sp. nov. ( Figs. 1 , 2 )

Leaves narrowed toward the base, divergent and recurved from the middle; inflorescence small, capituliform, congested, sunk in the center of the rosette; sepals linear, free, exposing most of the petals, white except for the red base, with the apex first attenuate then rounded; petals magenta with white margins, apex cucullate to slightly reflexed; anthers sagittate and dorsifixed; stigma simple-erect; epigynous tube narrow cylindrical, white, floccose.

Type — BRAZIL. Rondônia: Nova Mamoré, BR 421 ou linha D, estrada vicinal de acesso ao Parque Estadual de Guarajá-Mirim, proximidades do fim da linha, propriedade do Sr. João, trilha com início em 10º 30’ 58.1” S, 64º 40’ 58.8” W, 188 m. elevevation, 25 May 2012, fl. cult. July 2013, D. P. Saraiva & N. Bigio 361 (holotype RB!).

Plant rupicolous, 30 cm tall. Leaves divergent with recurved middle and apex, coriaceous; sheaths ca. 3 × 3 cm, ovate, brown, with brown-pannose trichomes on both surfaces, margins spinose, spines 1–2 mm long; blade ca. 58 cm long, distinctly narrowed toward the base, ca. 1.5 cm wide at the base and ca. 5 cm wide towards the middle, linear-oblanceolate, green, lepidote, margins spinose, spines 1–2 mm long, apex acuminate. Peduncle erect, inconspicuous, ca. 2 cm long, 5 mm in diameter, white, floccose; peduncle bracts coriaceous; sheaths ca. 3.5 × 3.5 cm, very widely ovate, brown, pannose to floccose, margins spinose, spines ca. 1 mm long; blades 4.6–10.7 × 2.4–2.7 cm, lanceolate, red, lepidote, margins spinose, spines ca. 1 mm long, apex attenuate. Inflorescence compound, capituliform, ca. 5 cm long, 3.5 cm in diameter, sunk in the center of the rosette; rachis white, floccose; primary bracts similar to the peduncle bracts, 3.2–3.5 × 0.3–1.2 cm, linear-oblong, entirely cream-colored to sometimes with red apex, lepidote, margins spinose to entire, spines 1 mm long, apex apiculate to rounded; fascicles with 2–3 flowers. Floral bracts ca. 3 × 0.2 cm, linear, asymmetric, cream-colored to red, carinate, lepidote to floccose at the apex, entire, apex rounded and apiculate. Flowers 3.8–4 cm long, polystichous, pedicellate; pedicel inconspicuous, 2–3 mm long; sepals 1.7–2 × 0.2 cm, linear, symmetric, white with a red base, glabrous to sparsely lepidote at the base, carinate, free, entire, apex first attenuate then rounded, cucullate; petals ca. 2.1 × 0.5–0.6 cm, oblong, magenta with white base and margins, glabrous, forming a basal tube with the stamen for ca. 5 mm, margins entire, apex rounded to slightly emarginate, cucullate to slightly reflexed; stamens included, ca. 1.6 cm long, monadelphous, tube 6 mm long, anthers sagittate, dorsifixed near at 1/5 of its length above the base, yellow, ovary ca. 15.5 × 6, 5 mm, oval, white; style ca. 10 mm long, white; stigma included, ca. 2 mm long, simple-erect, white; epigynous tube 1.4–1.8 cm long, 2–3 mm in diameter, white. Fruits unknown.

Distribution and habitat: — Bromelia gracilisepala occurs in the Amazon biome and is known from the type locality only. The species is very common on the hillside among scrubs and rocks, in a “cerrado rupestre” (shrub and tree formation on rocky soil). Although this is at the northwest frontier of Brazil, the species probably also occurs in Bolivia. Bromelia gracilisepala may be also present in the Parque Estadual de Garajá-Mirim, since the collection location is situated at the edge of the park, as well as in the Parque Nacional de Pacaás Novos, which has a similar vegetation.

Conservation status: —Since this new species is known only from a single population, outside a conservation unit, and it is not well known, we do not have adequate information to determine whether or not the new species is threatened with extinction. Following recommendations of IUCN (2010), they should be considered Bromelia gracilisepala as Data Deficient (DD).

Etymology: —“Gracilis” means slim, and the name “gracilisepala ” is related to the narrow shape of the sepals, which is an uncommon feature in Bromelia .

Comments:—According to the classification of Mez(1891), Bromelia gracilisepala should be included in Bromelia subg. Distiacanthus ( Baker, 1889: 13) Mez (1891: 186) the only monophyletic subgenus in Bromelia ( Monteiro 2009) , because of the leaf blade narrowed at the base and resembling a petiole, even though other morphological characters are distinctive ( Table 1).

gracilisepala .

Bromelia gracilisepala is also less robust, compared with some species of Bromelia that occur in Amazonia [i.e., B. scarlatina ( Linden, 1869:4) E. Morren (1881: 164) and B. morreniana ( Regel 1888: 157) Mez 1891: 186 ] ( Fig. 3 , Table 1). This species is especially distinctive because of the narrow sepals exposing the most of the petals.

Although B. gracilisepala is related to species of Distiacanthus, it is morphologically closely associated, especially in floral characters, with B. horstii Rauh (1985:54) , which occurs in Mato Grosso on rock outcrops. However, the latter species is smaller, with differently shaped narrow triangular leaves (vs. linear-oblanceolate), lanceolate sepals (vs. linear) and white anthers (vs. yellow). The new species is also quite similar to B. flemingii I. Ramirez & Carnevali (1996: 206) from Venezuela, but differs in the linear-oblanceolate leaf blade shape (vs. triangular-oblong), pedicellate flowers (pedicels inconspicuous vs. sessile flowers), sepal dimensions (1.7–2 × 0.2 cm vs. 5–5.9 × 0.5 cm), free (vs. connate) and linear (vs. triangular), and petals magenta with white base and margins (vs. pink-purple) ( Figure 2 and 3 , Table 1).

Figures

FIGURE 1. Bromelia gracilisepala (D.P. Saraiva 361, RB). A. Habit. B. Leaf. C. Indumentum present on the leaf sheaths (detail). D. Inflorescence. E. Inflorescence with primary bracts. F. Primary bract. G. Flower with floral bract. H. Floral bract. I. Open flower. J. Stamen. K. Stigma and style.

FIGURE 2. Bromelia gracilisepala. A. Holotype. B. Habit. C. Inflorescence. B–C photos by R. G. B. Silva.

FIGURE 3. Habit of Bromelia species. A. Bromelia morreniana. B. Bromelia scarlatina. C. Bromelia flemingii. D. Bromelia horstii. A photo by R. F. Monteiro B–C photos by B. Holst, D photo by B. R. Silva.