Vriesea mimosoensis D.R. Couto, Kessous

Couto, Dayvid R., Kessous, Igor M. & Costa, Andrea F., 2020, A new species of Vriesea (Bromeliaceae) from Pedra dos Pontões, Espírito Santo, Brazil: an area of endemism for Bromeliaceae at Atlantic Forest, Phytotaxa 433 (2), pp. 167-173 : 168-171

Vriesea mimosoensis D.R. Couto, Kessous & A.F. Costa, sp. nov. ( Figures 1–2 )

Diagnose:— This new species is distinguished from Vriesea fluviatilis by the terrestrial habitat (vs. epiphytic), longer inflorescence penduncle (43–60 cm vs. 23–30 cm), peduncle bracts shorter (4–4.5 cm vs. 5–8 cm), ovate to triangular (vs. oblong to ovate), red with green apices (vs. red-orange with green or yellow apex), the upper ones glabrous on adaxial surface (vs. lepidote on both sides), and by the carinate floral bracts (vs. ecarinate).

Type: — BRAZIL. Espírito Santo: Mimoso do Sul, Pedra dos Pontões, matinha nebular sobre inselberg, propriedade Sr. Roberto Belatto, 1.300 m. elev., 11 Oct 2015, D. R.Couto 3241 & F. C. Guerra Júnior (holotype R!, isotype MBML!).

Plant terrestrial or rarely epiphytic, mesomorphic, 58–78 cm when flowering, propagating by basal axillary shoots. Leaves ca. 15, forming a funnel-shaped rosette; sheath elliptic, 6.5–12 × 4–6 cm, green-whitish, densely lepidote on both faces, chartaceous; blade linear, 17.5–51 × 3–3.5 cm, green, sparsely lepidote on both faces, arched, apex acuminate and apiculate. Inflorescence simple, densely 16–24 flowered, 58–78 cm long, suberect, flowers distichous, 5–9 mm apart, suberect, with apical sterile bracts; peduncle suberect, 43–60 cm long, 3.4–5.4 mm in diameter, glabrous; peduncle bracts erect, imbricate, ovate to triangular, 4–4.5 × 2–2.4 cm, the lower ones green, densely lepidote on both faces, the upper ones red, greenish towards the apex, lepidote on the abaxial face, glabrous on the adaxial face; rachis geniculate, 16–17.5 cm long, 2–3.6 mm in diameter, red to green-yellowish, glabrous. Floral bracts ovate-elliptic, apex obtuse, incurved, 4.2–4.5 × 2.8–3 cm, carinate, involute, red in the lower part, yellow-greenish in the middle and greenish toward the apex, longer than the sepals, densely lepidote on adaxial side, glabrous on abaxial side. Flowers with diurnal anthesis, ca. 6.3 cm long, pedicel green, 4–5 mm long; sepals oblong to elliptic, apex acute, 34–38 × 10–11 mm, yellow, greenish toward the apex, only two of them inconspicuously carinate, glabrous, free; petals oblanceolate to linear, ca. 50 × 11 mm, apex rounded, recurved, yellow-greenish, apex green, glabrous, connate at the base to 5–5.5 mm wide; petal appendages with acute apex, ca. 10.6 × 4.8 mm, free for 6.5 mm; stamens exerted for ca. 8.4 mm, filaments complanate at the base, the antepetalous ones adnate for ca. 4.3 mm to the petals, white; ovary superior, ca. 6.5 mm long; style ca. 51 mm long, exerted; stigma of the convolute-blade type, green. Capsules ellipsoid, ca. 47 mm long, 8 mm diameter. Seeds unknown.

Phenology: —Flowering specimens were found in October and with immature fruits in February.

Distribution and ecology: — V. mimosoensis is endemic to Pedra dos Pontões, inside the cloud forest. The locality preserves an important remnant of the Atlantic Forest of the south of Espírito Santo, which is a region that has many granite inselbergs. Furthermore, this locality is recognized for its great biological importance, mainly because of the endemic and endangered plant species ( Couto et al. 2013; 2016; 2017), as for example Neoregelia dayvidiana Leme & A.P. Fontana ( Leme et al. 2009: 162) and Pitcairnia abyssicola Leme & L. Kollmann ( Leme et al. 2009: 157), both described from this area. The habitat of V. mimosoensis is restricted to cloud forests near to the top of these mountains, around 1300 m elevation. It was observed as growing as sparse individuals on shallow, well drained soil and with a canopy between 3-6 m height with a rich vascular epiphytic flora. Although Vriesea species are mainly epiphytic ( Zotz et al. 2013; Ramos et al. 2019), this new taxon occurs primarily as terrestrial, with few exceptions, as in the case of the collection V.C. Manhães 33 (MBML!).

Delimited areas with two or more endemic taxa are considered areas of endemism ( Szumik & Goloboff 2004). Here, we presented this new species, which is added to two other Bromeliaceae endemic to Pedra dos Pontões ( N. dayvidiana and P. abyssicola ) demonstrating that this is an area of endemism for Bromeliaceae . With this data it is expected that conservation actions will be taken by the public power in order to preserve the biodiversity richness of this important region.

Conservation status: — Vriesea mimosoensis can be considered critically endangered (CR B2ab (ii, iii)) according to IUCN criteria, since its area of occupancy (AOO) is estimated to be less than 10 km 2 with a severely fragmented habitat. In addition, its occurrence is currently known to be concentrate in a single locality, and its habitat is in continuing decline, mainly due to the practice of tourism that has been growing disorderly in the region.

Etymology: —The epithet “mimosoensis ” refers to the county of Mimoso do Sul, where Pedra dos Pontões is situated, the habitat of this new taxon.

Paratypes:— BRAZIL. Espírito Santo: Mimoso do Sul , Pedra dos Pontões, Matinha Nebular sobre inselberg, terrestre em sub-bosque, 1300 m elev., 01 February 2016, D. R.Couto 3287 & T. M. Francisco ( RB!) ; idem, epífita, 27 May 2007, V. C. Manhães 33 ( MBML!) .

Discussion: — Vriesea mimosoensis belongs to the group of species with diurnal flower ( Vriesea sect. Vriesea sensu Smith & Downs 1977 ) characterized by red or yellow floral bracts, oblong to linear petals, forming a tubular corolla, exerted stamens, and hummingbird pollination syndrome. Furthermore, due to the floral characteristics observed in this new taxon, as a simple inflorescence, and involute floral bracts, this allows us to identify this taxon as belonging to the morphological group of V. ensiformis ( Costa et al. 2015, Kessous 2016) which is represented by 13 taxa diversified in the Atlantic Forest domain. The different morphotypes throughout the distribution range of this group creates difficulties in delimiting the taxa ( Kessous 2016).

Vriesea mimosoensis is morphologically related to V. fluviatilis , differing by the nearly exclusively terrestrial habitat (vs. epiphytic), elliptic leaf sheath (vs. obovate), acuminate apex of the leaf blades (vs. obtuse to acute), peduncle of the inflorescence longer (43–60 cm vs. 23–30 cm), with shorter bracts (4–4.5 cm vs. 5–8.2 cm), ovate to triangular (vs. oblong to ovate), red with green apex (vs. red-orange with green or yellow apex), upper ones glabrous in the abaxial surface (vs. lepidote on both sides), and by the carinate floral bracts (vs. ecarinate). While V. mimosoensis is terrestrial in the cloud forests of the south of the state of Espírito Santo, V. fluviatilis inhabits the Serra do Mar in Rio de Janeiro as an epiphyte.

It also differs from V. ensiformis by its terrestrial habit (vs. epiphyte), suberect peduncle (vs. erect), 43–60 cm long (vs. 25–50 cm), peduncle bracts ovate or triangular (vs. elliptic and oblong); geniculate rachis (vs. straight), up to 17.5 cm long. (vs. up to 40 cm) and 2–3.6 mm in diameter (vs. 4–7 mm), yellow-greenish (vs. red to greenish when fruiting), floral bracts red to green towards the apex (vs. red or red with yellow apex [ V.ensiformis var. bicolor ]); flowers 4.9–9 mm apart (vs. 10–20 mm); sepals yellow with greenish apex (vs. broadly yellow); petals oblanceolate to linear (vs. narrowly-elliptic), greenish-yellow with green apex (vs. yellow), connate at the for 5–5.5 mm (vs. ca. 2 mm), petal appendages free for 6.5 mm (vs. ca. 4 mm).

Additionally it differs from V. mourae Kessous, B. Neves & A.F. Costa (2018: 46), by the distinctly smaller size when in flower (58–78 cm vs. 115–135 cm), shorter blades (up to 51 cm vs. up to 87 cm), sheaths elliptic (vs. oblong) and shorter (6,5– 12 cm vs. 14–19 cm), shorter inflorescence (58–78 cm vs. 110–120 cm), with smaller number of flowers (up to 24 vs. up to 35 flowers), shorter peduncle (up to 60 cm vs. up to 75 cm), shorter peduncle bracts (4–4.5 cm vs. 5–8 cm), floral bract yellow-greenish in the middle and greenish toward the apex (vs. red on lower portion, yellow in the middle and greenish toward apex); smaller flower (ca. 40 mm vs. 75 mm); shorter sepals (34–38 x 10–11 mm vs. 40–45 x 15 mm), with acute apex (vs. rounded), narrower petals (ca. 11 mm vs. 12–14 mm wide) and petals connate for 5–5.5 mm (vs. ca. 4.5 mm).

Figures

FIGURE 1. Vriesea mimosoensis D.R.Couto, Kessous & A.F. Costa (D.R. Couto 3241 & F.C. Guerra-Júnior). A. Pedra dos Pontões, Mimoso do Sul, ES. B. Habitat, population inside of the cloud forest. C. Details of reproductive characteristics: floral bracts and flowers. D. Infrutescence. (Photo: D.R Couto)

FIGURE 2. Vriesea mimosoensis D.R.Couto, Kessous & A.F. Costa (D.R. Couto 3241 & F.C. Guerra-Júnior). A. Inflorescence. B. Infrutescence. C. Stigma. D. Pistil. E. Floral bract. F. Sepal. G. Petal and anthers. H. Petal appendages. I. Leaf. J. Habit.