Dyckia rondonopolitana 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 : 29-31

Dyckia rondonopolitana Leme , sp. nov. ( Figs. 11 , G–L, 12 , A–E)

This new species resembles Dyckia dawsonii due to the long marginal spines of the leaf blades, but the spines are shorter than the width of the leaf blades, and it further differs by the much shorter and densely flowered inflorescence, with a higher number of flowers and by longer sepals and petals.

Type:— BRAZIL. Mato Grosso: Rondonópolis, Limas, Morro Pirogero , near the road MT- 130, 506 m elevation, 16° 12’ 45.1” S 54° 29’ 36.9” W, 28 April 2006, W . Kranz 123 (holotype RB!) .

Plants saxicolous, flowering ca. 38 cm high. Leaves 20–30 in number, densely rosulate, coriaceous; sheaths broader than the blades; blades narrowly triangular, slighly canaliculate toward the apex, arcuate, recurved toward the apex, 20–22 cm long, 1–1.5 cm wide at the base, 3–5 mm thick near the base, green to reddish, opaque, densely white lepidote abaxially with the trichomes obscuring the color of the blades, adaxially densely to subdensely white lepidote toward the base, the trichomes not obscuring the color of the blades, and glabrescent toward the apex, finely nerved abaxially, apex long acuminate-caudate, acicular, pungent, margins coarsely white lepidote to glabrous, subdensely spinose, spines 3–6 mm long, 6–12 mm apart, acicular, spreading to retrorse, pale colored at the base and yellowish-castaneous near the apex, densely white lepidote. Peduncle oriented at a 45°angle, ca. 20 cm long, 4–5 mm in diameter, glabrous, reddish; peduncle bracts subtriangular-ovate, apex acuminate-caudate, membranaceous, 6–15 × 5–8 mm, greenish-yellow to reddish toward the apex, becaming stramineous near the apex, nerved, white lepidote to glabrous, erect, the basal ones remotely spinulose, exceeding the internodes. Inflorescence suberect, ca. 14 cm long, glabrous, densely flowered, rachis straight, subangulose, yellowish-orange, glabrous, 3–4 mm in diameter; floral bracts the basal ones resembling the upper peduncle bracts, broadly subtriangular-ovate, acuminate to acute, 6–10 × 5–9 mm, remotely crenulate to entire, ecarinate, glabrous, distinctly shorter than the sepals, convex, membranaceous, greenish-yellow. Flowers ca. 40 in number, 17–18 mm long, subspreading to forming an angle of 60° with the rachis at anthesis, densely arranged; pedicels inconspicuous, stout, ca. 3 mm long, 4–5 mm in diameter at the apex; sepals symmetric, ovate, convex, apex obtuse or erose, ca. 8 × 6.5 mm, yellow, glabrous, membranaceous; petals symmetric, spathulate, apex subacute, connate at the base for ca. 2 mm to form a common tube with the filaments, ca. 13 × 10 mm, ecarinate, yellow, slightly convergent toward the apex and forming a tubular corolla; stamens exceeding the corolla by a fraction of the anthers; filaments complanate, connate at the base for ca. 2 mm to form a common tube with the petals, free above it, 10–11 × 1.5 mm, whitish; anthers narrowly subtriangular, recurved at anthesis, ca. 4 mm long, base bilobed, apex acuminate, fixed near the base; pistil ca. 6 mm long, distinctly surpassed by the anthers; stigma conduplicatespiral, blades distinctly scalloped-lacerate, yellow, ca. 1 mm long; style ca. 0.5 mm long, yellowish; ovary suboblong-ovate, ca. 3.5 mm long, ca. 1.5 mm in diameter, yellowish. Capsules unknown.

Distribution and habitat:—This new species is known only from the type locality, where it lives on reddish sandstone outcrops in Cerrado vegetation, on a hill called “Pirogero”, in the Brazilian central state of Mato Grosso, at an elevation of ca. 500 m. It is rupicolous dweller in full sun exposure, forming dense groups of plants.

Etymology:—The name of this new species is a direct reference to the county of Rondonópolis, Mato Grosso, where it was originally collected.

Observations:— Dyckia rondonopolitana can be morphologically associated to D. dawsonii Smith (1957: 2) , an endemic species from Serra Dourada, state of Goiás. However, this new species differs from it by its broader leaf blades (1–1.5 cm vs. 0.7 cm wide), even broader than the length of the marginal spines (vs. distal portion narrower than the length of the marginal spines), marginal spines shorter (3-5 mm vs. 5–7 mm long), inflorescence shorter (ca. 14 cm vs. 25–30 cm long), densely flowered (vs. laxly flowered) and bearing more flowers (ca. 40 vs. 20–30 in number), longer sepals (ca. 8 mm vs. 5–6 mm long) and by the longer petals (ca. 13 mm vs. ca. 9 mm long).

Figures

FIGURE 11. A–F. Dyckia pottiorum (Leme et al. 8579). A. Leaf blade. B. Floral bract. C. Flower. D. Sepal. E. Petal and stamen. F. Pistil. G–L. Dyckia rondonopolitana (Kranz 123). G. Basal portion of the leaf. H. Floral bract. I. Flower. J. Sepal. K. Petal and stamens. L. Pistil. Scale bars = 1 cm, except for L, bar = 0.4 cm.

FIGURE 12. A–E. Dyckia rondonopolitana (Kranz 123). A. Habit. B. Detail of leaf rosette. C. Basal portion of the inflorescence. D. Flowers. E. General view of the habitat at the type locality, with Morro Pirogero in the brackground.