Dyckia areniticola Leme, 2012

Leme, Elton M. C., Ribeiro, Otávio B. C. & Miranda, Zenilton De J. G., 2012, New species of Dyckia (Bromeliaceae) from Brazil, Phytotaxa 67 (1), pp. 9-37 : 13-15

Dyckia areniticola Leme , sp. nov. ( Figs. 2 , G–K, 3 , A–F)

This new species is characterized by rosettes with numerous leaves, which are narrow and bearing well developed, usually retrosely curved marginal spines. It differs from Dyckia pumila mainly by the glabrous peduncle, basal peduncle bracts equaling to exceeding the internodes, glabrous inflorescence, and by the smaller flowers with the corolla slightly convergent toward the apex.

Type:— BRAZIL. Mato Grosso: Chapada dos Guimarães, Cidade de Pedra , 640 m elevation, 15º 11’ 50” S, 55º 53’ 12” W, 5 November 2006, E . Leme 6964 & S. Gonzalez (holotype RB!, isotype HB!) .

Plants saxicolous, flowering 30–38 cm high. Leaves 30–40 in number, densely rosulate, coriaceous; sheaths broader than the blades; blades narrowly triangular, slightly canaliculate toward the apex, arcuate, 15–22 cm long, 1–1.3 cm wide at the base, 2–3 mm thick near the base, green to dark reddish, opaque, densely whitelepidote abaxially with the trichomes completely obscuring the color of the blades, adaxially densely white lepidote toward the base, trichomes not obscuring the color of the blades, finely nerved abaxially, apex long acuminate-caudate, acicular, pungent, margins coarsely white lepidote to glabrous, subdensely spinose, spines 2.5–4 mm long, 3–12 mm apart, acicular, spreading to retrorse, pale colored at the base and yellowishcastaneous near the apex, glabrous. Peduncle erect, 20–25 cm long, 2–3 mm in diameter, glabrous, sulcate toward the apex, dark reddish to greenish; peduncle bracts broadly ovate at the base with a narrowly sublinear-triangular, acuminate-caudate apex, rigid, 8–30 × 3–5 mm, stramineous, nerved, glabrous, erect, the basal ones remotely spinulose, exceeding to equaling the internodes, the median to upper ones entire, shorter than the internodes, sometimes carinate near the apex. Inflorescence suberect, 6–14 cm long, glabrous, subdensely to densely flowered, rachis straight to flexuous toward the apex, subangulose, dark red to wine colored, glabrous, 1–3 mm in diameter; floral bracts the basal ones resembling the upper scape bracts but smaller, broadly ovate, acuminate, 6–7 × 3–5 mm, entire, ecarinate, glabrous, distinctly shorter than the sepals, convex, the upper ones suborbicular, acute and apiculate, exceeding the pedicels. Flowers 15–28 in number, 15–16 mm long, subspreading to forming an angle of 45° with the rachis at anthesis, subdensely to densely arranged; pedicels inconspicuous, stout, ca. 2 mm long, ca. 4 mm in diameter at the apex; sepals symmetric, ovate to suborbicular, convex, apex obtuse to acute and sometimes narrowly emarginate, slightly cucullate, 7–8 × 5–8 mm, red or orange-red, glabrous; petals symmetric, spathulate from a narrower base, apex acute to emarginate, connate at the base for 2–2.5 mm to form a common tube with the filaments, 11–13 × 6–10 mm, ecarinate, orange to reddish-orange, slightly convergent toward the apex and forming a tubular corolla; stamens exceeding the corolla by a fraction of the anthers; filaments complanate, free above the common tube with the petals, 8–10 × 1.5–2 mm, yellowish; anthers sublinear, slightly to distinctly recurved, 4–4.5 mm long, base bilobed, apex acuminate, fixed near the base; pistil 7–8 mm long, distinctly surpassed by the anthers; stigma conduplicate-spiral, blades scalloped-lacerate, orange; style ca. 1 mm long, yellowish; ovary suboblong-ovate, ca. 5 mm long, ca. 2 mm in diameter, yellowish. Capsules unknown.

Distribution and habitat:— Dyckia areniticola is a typical dweller of sandstone outcrops of Chapada dos Guimarães, Mato Grosso, central Brazil, at an elevation from 600 to 800 m. Plants occur as solitary individuals in crevices mainly on vertical sandstone walls or densely grouped on less inclined rock surfaces, usually under full sun exposure.

Etymology:—The name chosen for this new species is a reference to the sandstone outcrops where it usually grows, which are called “arenito” and characteristic of the landscape in the higher parts of the Chapada dos Guimarães region.

Additional specimens examined (paratypes):–– BRAZIL. Mato Grosso: Chapada dos Guimarães, Cidade de Pedra , 640 m elevation, 15º 11’ 50” S, 55º 53’ 12” W, 5 November 2006, E . Leme 6966 & S . Gonzalez ( RB); Chapada dos Guimarães, trilha para o Rio Sete de Setembro , 780 m elevation, 6 November 2006, E . Leme 6969 & S . Gonzalez ( RB) .

Observations:— Dyckia areniticola is closely related to D. pumila Smith (1966: 151) , differing from it by the broader leaf blades (1 – 1.3 cm vs. 0.7–0.8 cm wide at the base), the margins with longer spines (2.5–4 mm vs. 0.5–2 mm long), which are often retrorse (vs. mostly antrorse), glabrous peduncle (vs. sparsely to subdensely white lepidote with fimbriate trichomes), basal peduncle bracts equaling to exceeding the internodes (vs. all shorter than the internodes), glabrous inflorescence (vs. sparsely white lepidote except for the petals), flowers shorter (15 – 16 mm vs. 18 – 19 mm long) and more numerous (15 – 28 vs. 3–6 in number), and by the corolla slightly converging toward the apex (vs. not at all converging toward the apex).

Figures

FIGURE 2. A–F. Dyckia acutiflora (Leme 6806). A. Basal portion of the leaf blade. B. Floral bract. C. Flower. D. Sepal. E. Petal and stamens. F. Pistil. G–K. Dyckia areniticola (Leme 6964 & Gonzalez). G. Leaf blade. H. Flower. I. Sepals. J. Petal and stamens. K. Pistil. Scale bars = 1 cm.

FIGURE 3. Dyckia areniticola. A–B (Leme 6964 & Gonzalez). A. Habit. B. Basal portion of the inflorescence. C–E (Leme 6966 & Gonzalez). C. Habit. D. Inflorescence. E. Landscape view of Chapada dos Guimarães from Cidade de Pedra, habitat of D. areniticola. F. Population of D. areniticola.