Stigmatodon ilhanus Leme & D. R. Couto 2022, sp. nov

Autor: Leme, Elton M. C., Couto, Dayvid R., Kollmann, Ludovic J. C., Fraga, Claudio Nicoletti De
Rok vydání: 2022
Předmět:
DOI: 10.5281/zenodo.7471587
Popis: Stigmatodon ilhanus Leme & D.R. Couto, sp. nov. (Figs. 4 A–E) Diagnosis: ___ This new species is morphologically similar to S. rosulatulus, but can be differentiated by: leaf blades narrowly triangular (vs. suboblong to sublinear), completely obscured on both sides by a dense layer of cinereous trichomes (vs. the green or purple color not obscured by the trichomes except for the parts covered by white irregular crossbands), sepals vinaceous-nigrescent (vs. greenishcastaneous with vinaceous margins), petals greenish (vs. yellowish-white), with larger appendages (9–10 × 3 mm vs. ca. 7 x 2 mm), and stigma blades sparsely and inconspicuously papillate (vs. densely papillate). Type: — BRAZIL. Bahia: Guaratinga, Buranhém, Pedra do Ferreiro, conjunto Fazenda Santa Clara, 536 m elevation, 16° 33’ 36.28” S, 40° 00’ 53.68” W, May 2015, A . Ilha s.n., cult. E . Leme 8997 (holotype RB!). Description:— Plants rupicolous, flowering ca. 42 cm tall. Leaves 25–30 in number, densely rosulate, thin coriaceous, forming a broadly funnelform rosette; sheath broadly elliptic, 6–8 × 5–7 cm, densely and minutely pale castaneous lepidote on both sides, nerved when dry; blade narrowly triangular, acuminate-caudate, nearly flat toward the apex, subspreading to recurved, 8–11 cm long, 2.5–3 cm wide at the base, completely covered on both sides with a dense layer of cinereous trichomes obscuring the color of the blade, margins reddish, inconspicuously truncate. Peduncle suberect or abruptly bending just above the rosette, 17–20 cm long, 0.3–0.4 cm in diameter, dark purplish to nigrescent, glabrous, not sulcate at anthesis; peduncle bracts the basal ones subfoliaceous, the upper ones ovate, attenuate and apiculate to obtuse, 14–20 × 8 mm, equaling to distinctly shorter than the internode, abaxially densely white lepidote mainly toward the apex, clasping the peduncle, nigrescent except for the stramineous margins. Inflorescence simple, suberect, linear in outline at anthesis, ca. 12 cm long, 7–8-flowered; main axis smooth at anthesis, nigrescent, glabrous, bluntly if at all angled, slightly flexuous, internodes 1–2 × 0.2–0.3 cm; floral bracts broadly ovate to broadly elliptic, obtuse, 8–13 × 7–9 mm, sparsely and inconspicuously white lepidote on both sides, ecarinate, remote, secund with the flowers at anthesis, thin coriaceous, lustrous, smooth, nigrescent, about reaching 1/3 of the sepal length. Flowers ca . 37 mm long (with petals extended), nocturnal, with a garlic odor, distichous, laxly disposed, distinctly secund at anthesis; pedicel 5–6 mm long, ca. 7 mm in diameter at distal end, stout, nigrescent, glabrous; sepals ovate, rounded, 17–18 × 9–10 mm, vinaceaous-nigrescent, sparsely and minutely white lepidote on both sides, smooth, ecarinate, thin coriaceous, apical margins membranaceous; petals obovate, apex broadly rounded and emarginate, recurved near the apex at anthesis, ca. 30 × 17 mm, pale greenish, thicker toward the base, bearing 2 appendages at the base; appendages 9–10 × 3 mm, spathulate, basally adnate to the petals for ca. 5 mm, apex bifid-caudate to caudate; corolla campanulate, 26–30 mm in diameter; stamens in pairs facing each petal at anthesis; filament free, 19–20 × 1.5 mm; anther ca . 7 mm long, dorsifixed near the base, base bilobed, apex obtuse; stigma tubo-laciniate type II, campanulate, margins entire to inconspicuously crenulate, sparsely and inconspicuously papillate, ca. 2.5 mm in diameter, green; ovules distinctly caudate at the distal end. Capsules unknown. Etymology: ___ The name of this new species honors the conservationist and climber André Ilha, who has brought countless bromeliad species found in difficult-to-access vertical cliffs from granitic inselbergs of southeastern Brazil to our attention. He documented this new species in the field and provided the specimens used in this study. Distribution and habitat:— Stigmatodon ilhanus is an ephilitic species, living on bare, nearly vertical granitic surfaces of inselbergs located in the district of Buranhém, county of Guaratinga, Bahia state, near the border with Minas Gerais. At the type locality, the heliophytic rosettes are scattered and form small to medium-sized groups of plants. Preliminary conservation status: ___ Vulnerable [VU: D2]. Stigmatodon ilhanus is only known from its type locality, at the Pedra do Ferreiro, a lowland inselberg from the southern region of Bahia, with the AOO of 4 km ² (AOO), and EOO undefined. Due to the apparent rarity and restricted distribution, with its small populations outside any conservation unit, and thus unprotected and prone to the effects of stochastic events in the near future, it seems prudent to include this species in the Vulnerable category [VU: D2]. However, the region of Guaratinga forms impressive inselberg landscapes, and new research in this region may change the conservation status of S. ilhanus. Observations: ___ Stigmatodon ilhanus is closely related to S. rosulatulus, living in ecologically similar habitats. This new species can be clearly distinguished mainly by the combination of leaves completely cinereous and obscured on both sides by a dense layer of trichomes (vs. leaves not obscured by the trichomes except for the parts covered by white irregular crossbands), and sepals vinaceous-nigrescent (vs. greenish-castaneous with vinaceous margins). Its stigma belongs to the tubo-laciniate type II, which allows grouping S. ilhanus with the species of Stigmatodon s.l. The stigma blades with sparse and inconspicuous papillae (fig. 1 J–K) differ from the densely papillate stigma of its close relative (figs. 1 M–N).
Published as part of Leme, Elton M. C., Couto, Dayvid R., Kollmann, Ludovic J. C. & Fraga, Claudio Nicoletti De, 2022, Novelties in Stigmatodon (Bromeliaceae, Tillandsioideae), a genus endemic to Brazil: three new species, one new combination, and two new stigma types, pp. 233-249 in Phytotaxa 576 (3) on pages 239-241, DOI: 10.11646/phytotaxa.576.3.1, http://zenodo.org/record/7471603
Databáze: OpenAIRE
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