Research Article |
Corresponding author: Dayvid Rodrigues Couto ( dayvidrcouto@gmail.com ) Academic editor: João Farminhão
© 2023 Dayvid Rodrigues Couto, André Pavioti Fontana, Andrea Ferreira da Costa, Claudio Nicoletti de Fraga.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Couto DR, Fontana AP, da Costa AF, de Fraga CN (2023) A new epilithic bromeliad (Stigmatodon, Tillandsioideae) from Pedra dos Três Pontões, Espírito Santo, Brazil, with an emended combination for the genus. Plant Ecology and Evolution 156(2): 215-224. https://doi.org/10.5091/plecevo.98904
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Background and aims – Stigmatodon (Bromeliaceae) is a monophyletic genus currently comprising 33 species, all endemic to rocky outcrops, mainly inselbergs, from the Atlantic Forest and campos rupestres of the Espinhaço range, Brazil.
Material and methods – Our fieldwork in the inselbergs of the Atlantic Forest of the state of Espírito Santo led to the discovery of a new Stigmatodon species with a tubo-laciniate stigma type. Standard herbarium taxonomy practices were adopted to study the novelty. Morphological data were obtained from herbarium specimens and fresh material collected in the field.
Key results – Stigmatodon lemeanus is here described and illustrated. Diagnostic characters and affinities of the new species are discussed, accompanied by notes on its ecology, geographic distribution, and conservation status. A key to the species of Stigmatodon from Espírito Santo state is provided. The novelty is similar to S. goniorachis from coastal inselbergs of Rio de Janeiro and S. attenuatoides, another inselberg endemic from southern Espírito Santo. Stigmatodon lemeanus is preliminarily assessed as Vulnerable (VU) according to the IUCN Red List criteria. Additionally, we present a new combination of Tillandsia oligantha in Stigmatodon, correcting a nomenclatural error.
Atlantic Forest, Brazilian endemics, campo rupestre, inselbergs, taxonomy, Vrieseinae
On isolated granitic and/or gneissic outcrops, known as inselbergs, plant communities with different ecological requirements inhabit different vegetational habitats, such as mats, shallow depressions, ephemeral flush vegetation, rock pools, and crevices (
Stigmatodon (Bromeliaceae, Tillandsioideae) was created to accommodate 18 lithophytic species that were formerly included in Vriesea Lindl. (
Currently, Stigmatodon comprises 33 species (
A total of 16 species of Stigmatodon occur in the State of Espírito Santo, which encompasses several mountain ranges. In the central region of the State rises the Serra do Castelo, or Serra Capixaba (
During field expeditions, a new rock-climbing species of Stigmatodon was found in this locality, growing exclusively on large inselberg vertical walls. This new taxon is described and illustrated in this work, its conservation status assessed, and its taxonomic affinities discussed. In addition, this paper provides an emended key for the species of Stigmatodon from Espírito Santo and a nomenclatural note for Stigmatodon oliganthus.
Morphological data were obtained by studying herbarium specimens and fresh material collected randomly in pre-selected sites during fieldwork in Bahia and Espírito Santo. Descriptions and illustrations are based on both living and dried material, which were studied using a stereomicroscope Motic K700; the descriptive terminology follows
Data on the distribution of the new and related species, gathered from field notes and herbarium labels, were plotted on a map using DIVA-GIS v.5.2 (
BRAZIL – Espírito Santo • Afonso Cláudio, Pedra dos Três Pontões, inselberg, epilithic on vertical rock wall; 20°04’33”S, 41°02’39”W; 1078 m; 21 Oct. 2019; fl.; D.R. Couto & C.N. Fraga 4926; holotype: MBML [MBML055811]; isotype: RB.
Similar to Stigmatodon goniorachis (Baker) Leme, G.K.Br. & Barfuss but distinguished by the suberect to patent peduncle (vs erect to suberect) that is more robust with a diameter of 6.5–7.8 mm (vs 3.5–6.2 mm), the main axis with shorter internodes (8.5–9.5 mm vs 15–25 mm long) that supports fewer flowers (11–13 vs 14–32), the longer flowers (56–60 mm vs 35–40 mm long), the larger petals (38–39 × 17–21 mm vs 22–28 × 13–15 mm), the basal appendages with irregularly acute-dentate apex (vs irregularly bidentate), and the shorter stamens (19–22 mm vs 26–28 mm long).
Stigmatodon lemeanus. A. Habit. B. Leaf. C. Peduncle bract. D. Inflorescence before anthesis. E. Flower, frontal view with detail of the stamens arranged in two groups of three on each lateral side of the corolla. F. Flower, lateral view. G. Floral bract, adaxial side. H. Floral bract, abaxial side. I. Floral bract, detail of the thickest part at the base. J. Petal with two basal appendages. K. Basal appendages, details. L. Stamen. M. Pistil. From the holotype D.R. Couto & C.N. Fraga 4926 (MBML). Drawn by Joelcio Freitas.
Lithophytic herb, 50–67 cm tall when flowering, propagating by basal shoots. Stem long, creeping, 7–20 cm in length. Leaves 12–20 in number, rosulate, thickly coriaceous, forming a funnelform rosette; sheath elliptic, 10–14 × 6–8.5 cm, densely and minutely castaneous-lepidote on both sides; blade narrowly triangular, apex acuminate-caudate, recurved, flat, suberect to arcuate, (11–)17–20 cm long, 2–2.8 cm wide at the base, green on both sides and usually with purplish-vinaceous spots on the adaxial side, usually vinaceous along margins, densely white-lepidote on both sides, with trichomes forming white crossbands adaxially, not obscuring the green colour of the blade, margins truncate, ca 0.5 mm thick. Inflorescence simple, ascending, 14–17 cm long, apex obtuse before and at anthesis, 11–13 flowered; peduncle suberect to patent, 35–42 cm long, 6.5–7.8 mm in diameter, green, glabrous, smooth at anthesis, sulcate in sicco; peduncle bracts subfoliaceous at the base, ovate above, apex obtuse-acuminate to apiculate, 2.5–3.5 × 2.4–2.8 cm, erect, imbricate, exceeding the internodes, green and usually with purplish-vinaceous spots on the adaxial side, densely lepidote abaxially, sparsely white-lepidote becoming denser towards the apex adaxially, smooth at anthesis; main axis smooth at anthesis, sulcate in sicco, green, glabrous, internodes 8.5–9.5 mm long; floral bracts broadly ovate, apex obtuse, 27–30 × 40–42 mm, shorter than sepals, green at anthesis, densely lepidote abaxially, adaxially glabrous, ecarinate, secund with the flowers before and during anthesis, coriaceous, thicker toward the base, smooth at anthesis, corrugate-sulcate in sicco. Flowers 56–60 mm long, night-blooming, with garlic scent and producing translucent mucilage, distichous, densely disposed, secund at anthesis; pedicel 9.5–11 mm long, 9–11 mm in diameter at distal end, stout, green, glabrous; sepals obovate, apex obtuse to rounded, (22–) 30–35 × (15–)21–23.5 mm, green, glabrous on adaxial side, densely lepidote abaxially, thick and coriaceous near the base, margins membranaceous; corolla 33–37 mm in diameter; petals obovate, apex rounded to emarginate, recurved near the apex at anthesis, 38–39 × 17–21 mm, greenish-white, strongly thickened with membranous margins, bearing 2 appendages at the base; appendages 9.5–11.6 × 3–3.8 mm, spathulate, basally adnate to the petals for 4.5–6.5 mm, apex irregularly acute-dentate; filaments free, complanate, 19–22 × 1.7–2 mm wide, white; anthers 8.5–9.5 mm long, dorsifixed near the base, base bilobed, apex obtuse, arranged in 2 groups of three on each lateral side of the corolla at anthesis; pistil equalling or exceeding the stamens; ovary superior, 5.6–7.4 mm long; ovules caudate; style 24.5–27 mm long, green; stigma tubo-laciniate type I, denticulate at the margins, 1.7–1.8 mm in diameter, green. Fruits a capsule, ellipsoid, apex apiculate, 32–45 mm long, 9.5–10.5 mm diameter, brown. Seeds fusiform, 3–4 mm long, brown; basal coma 15–21 mm long, beige; apical coma 1–1.6 mm, beige.
Stigmatodon lemeanus. A–B. Plants in situ at the type locality. C. Flowering individual in cultivation. D. Lateral view of the flower and floral bract. E. Frontal view of the flower. F. Details of the tubo-laciniate stigma and anthers. Photographs: A, C–F by Dayvid R. Couto, B by André P. Fontana.
Stigmatodon lemeanus is endemic to Pedra dos Três Pontões, from the county of Afonso Cláudio in the central region of Espírito Santo, Brazil (Fig.
Geographic distribution of the 16 species of Stigmatodon on the inselbergs of Espírito Santo. A. S. amadoi, S. apparicianus, S. attenuatoides, S. belloi, S. bifidus. B. S. euclidianus, S. fontellanus, S. funebris, S. harrylutheri, S. magnibracteatus. C. S. multifoliatus, S. plurifolius, S. sanctateresensis, S. vellozicolus, S. viridibracteatus. D. S. lemeanus.
Stigmatodon lemeanus. A–B. General view of the landscape at the type locality, highlighting the large and vertical pointed peaks of Pedra dos Três Pontões. C. Detail of the population on a vertical rock wall alongside sparse individuals of Pitcairnia diversifolia; some individuals grow close to the base of the slope, which facilitated the collection of some specimens for the study and description of the new species. Photographs: A by André P. Fontana, B–C by Claudio N. Fraga.
The plant is epilithic, heliophilic, living on bare and vertical rock walls of inselbergs, where it forms large populations (Figs
Flowers were recorded in October and fruits from May to October.
The specific epithet honours our friend Dr Elton Martinez Carvalho Leme (1960−), from Rio de Janeiro, Brazil, whose personal efforts have substantially contributed to the knowledge of the diversity, taxonomy, and systematics of Brazilian bromeliads. In addition, Dr Elton Leme is one of the authors of the genus Stigmatodon and has greatly contributed to the knowledge of these plants.
Vulnerable: VU D2. The new species is known from only one very small population within a protected area, with an AOO of 4 km2. These figures fall within the limits for Critically Endangered (CR), based on criterion B2 (area of occupancy), taking into account only the number of locations or severely fragmented areas, which can lead to a continuous decline in the extent of occurrence, area of occupancy and quality of habitat of the new species. However, population isolation and fragmentation are natural conditions on inselbergs, thus evaluations of plant distribution on inselbergs probably yield overestimated values of AOO and EOO (
BRAZIL – Espírito Santo • Afonso Cláudio, Pedra dos Três Pontões, inselberg, epilithic on vertical rock wall; 20°04’33”S, 41°02’39”W; 1078 m; 21 Oct. 2019; fr.; D.R. Couto & C.N. Fraga 4921; R • Afonso Cláudio, Pedra dos Três Pontões, rupícola no sol em paredão vertical; 18 May 2007; fr.; A.P. Fontana et al. 3386; MBML [MBML00029444].
Stigmatodon lemeanus is morphologically related to S. goniorachis, differing by the fewer number of leaves per rosette up to 20 (vs up to 30), acuminate-caudate leaf blade apex (vs acute apex), green, and usually with purplish-wine spots in the adaxial surface, usually vinaceous along margins (vs green); ovate peduncle bracts (vs elliptic); the main axis densely flowered at anthesis (vs laxly flowered), broadly ovate floral bracts (vs elliptic-ovate to suborbiculate) that are wider (40–43 mm vs 13–20 mm long); and the larger sepals (30–35 × 21–23.5 mm vs 21–30 × 15–19 mm), in addition to the characters cited in the diagnosis. Furthermore, while S. lemeanus is endemic to inselbergs in the mountainous region of Espírito Santo (> 1,000 m elevation), S. goniorachis is endemic to vertical walls of several coastal inselbergs by the sea, in the city of Rio de Janeiro, Brazil. When compared with S. attenuatoides D.R.Couto, Manhães & A.F.Costa (
Tillandsia oligantha
Baker, The Journal of Botany, British and Foreign 25: 345. 1887. (
Vriesea oligantha
(Baker) Mez (
Stigmatodon oliganthus
(Baker) D.R.Couto & A.F.Costa, nom. inval. (
BRAZIL – Minas Gerais • Serra d’Ouro Branco; 10 Nov. 1884; fl.; Glaziou 15472; holotype: K [K000322056]; isotype: P [P00753328].
1. | Stigma of the convolute-blade type II (vrieseoid type II), epiphyte on Vellozia in inselberg vegetation | S. vellozicolus (Leme & J.A.Siqueira) D.R.Couto & A.F.Costa |
– | Stigma of the tubo-laciniate type, epilithic on inselberg vertical rock wall | 2 |
2. | Simple inflorescence | 3 |
– | Compound inflorescence | 14 |
3. | Leaf blades at least 10 cm long | 4 |
– | Leaf blades less than 10 cm long | 13 |
4. | Leaf blade less than 1 cm wide at the base, utricular rosette, forming non-impounding rosettes | S. plurifolius (Leme) Leme, G.K.Br. & Barfuss |
– | Leaf blade at least 1 cm wide at the base, infundibuliform rosette, forming impounding rosettes | 5 |
5. | Floral bracts smooth at anthesis | 6 |
– | Floral bracts strongly nervate-sulcate at anthesis | 7 |
6. | Leaf blade with acute apex, flowers ca 4 cm long, sepals with emarginate apex, petals slightly thickened | S. fontellanus (Leme & G.K.Br.) Leme, G.K.Br. & Barfuss |
– | Leaf blade with acuminate-caudate apex, flowers 5.5–6 cm long, sepals with obtuse apex, petals strongly thickened | S. lemeanus D.R.Couto, A.P.Fontana & Fraga |
7. | Leaves, 28–45 in number, blade up to 2.5 cm wide, with a truncate margin (ending very abruptly as if cut straight across) less than 1 mm thick, peduncle bracts smooth at anthesis | S. multifoliatus (Leme & G.K.Br) Leme, G.K.Br. & Barfuss |
– | Leaves, 15–25 in number, blade more than 2.5 cm wide, margins distinctly truncate thicker than 1 mm, peduncle bracts strongly nervate-sulcate at anthesis | 8 |
8. | Greyish-green leaf blades | S. apparicianus (E.Pereira & Reitz) Leme, G.K.Br. & Barfuss |
– | Cinereous leaf blades | 9 |
9. | Peduncle bracts ovate-lanceolate, more than 45 cm long | S. magnibracteatus (Leme & L.Kollmann) Leme, G.K.Br. & Barfuss |
– | Peduncle bracts ovate, up to 45 cm long | 10 |
10. | Floral bracts green, smooth, inconspicuously corrugate-sulcate near the apex at anthesis | S. viridibracteatus D.R.Couto, Fraga & Leme |
– | Floral bracts castaneous, stramineous, strongly nervate-sulcate at anthesis | 11 |
11. | Leaf sheaths ovate-elliptic to elliptic, 9–12 cm wide, peduncle erect to suberect, flowers 4.7–5.1 cm long | S. euclidianus (Leme & G.K.Br.) Leme, G.K.Br. & Barfuss |
– | Leaf sheaths obovate to broadly elliptic, 7–8.5 cm wide, peduncle suberect, flowers 4–4.5 cm long | 12 |
12. | Leaf blade canaliculate toward the base, with margins 0.9–1 mm thick, peduncle bracts lax, sepals elliptic with obtuse-emarginate apex, appendages with bifid-caudate apex | S. bifidus (Leme & L.Kollmann) Leme, G.K.Br. & Barfuss |
– | Leaf blade flat toward the base, with margins 1.5–2 mm thick, peduncle bracts imbricate, sepal oblong to ovate with rounded apex, appendages with irregularly long-dentate to acuminate apex | S. harrylutheri (Leme & G.K.Br.) Leme, G.K.Br. & Barfuss |
13. | Leaf sheath 8.5–10 cm long (longer than the leaf blade), leaf blade ligulate, 5.8–7.3 cm long, flowers 2–3 cm long | S. amadoi (Leme) Leme, G.K.Br. & Barfuss |
– | Leaf sheath 7–9.8 cm long (equaling to the leaf blade length), leaf blade triangular, 7–10 cm long, flowers 3.4–4 cm long | S. sanctateresensis (Leme & L.Kollmann) Leme, G.K.Br. & Barfuss |
14. | Sublinear-triangular leaf blade, erect to the suberect peduncle, dark-wine floral bracts | S. funebris (L.B.Sm.) Leme, G.K.Br. & Barfuss |
– | Narrowly triangular leaf blade, peduncle strongly curved, vinaceous-green floral bracts | 15 |
15. | Leaf blades vinaceous-green, peduncle pending, 35–50 cm long | S. belloi (Leme) Leme, G.K.Br. & Barfuss |
– | Leaf blades green, concolorous, peduncle patent, 57–60 cm long | S. attenuatoides D.R.Couto, Manhães & A.F.Costa |
We thank Joelcio Freitas for the line drawing, the National Institute of the Atlantic Forest (INMA), in particular the staff of the herbarium MBML, and the Instituto de Pesquisas Jardim Botânico do Rio de Janeiro for sponsoring fieldwork in the state of Espírito Santo. DRC is supported by a research grant from the Nacional Council for Scientific and Technological Development (CNPq) in the Programa de Capacitação Institucional of the National Institute of the Atlantic Forest – INMA (PCI/INMA), from the Brazilian Ministry of Science, Technology, and Innovation (MCTI: grant no. 301141/2022-3). CNF’s biodiversity research is supported by grants from Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) through a Jovem Cientista do Nosso Estado Fellowship (grant no. 201280/2022) and CNPq in the Edital Universal (grant no. 422191/2021-3). AFC thanks to CNPq for the productivity grant (grant no. 311111/2021-1). Finally, we thank the reviewers and editor João Farminhão for their valuable suggestions that improved our manuscript.