Dyckia pottiorum 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 : 26-29

Dyckia pottiorum Leme , sp. nov. ( Figs. 10 , A–H, 11 , A–F)

This new species differs from its closest relatives, D. burchellii and D. coximensis , mainly by the distichously arranged leaves, and the basal floral bracts being distinctly shorter than the sepals.

Type:— BRAZIL. Mato Grosso do Sul: Corguinho , road MS 080 , Corguinho to Rio Negro , km 99, 493 m elevation, 19° 43’ 53.8” S 54° 54’ 45.2” W, 16 September 2011, E . Leme et al. 8579 (holotype RB!, isotype HB!) .

Plants saxicolous, nearly prostrate, flowering 23–52 cm high. Leaves 12 to 18 in number, distichously arranged, flabellate, coriaceous; sheaths reniform, the older ones forming a subglobose bulb, ca. 2.5 × 4 cm, castaneous at the base and greenish toward the apex, glabrous except for the densely and coarsely white lepidote upper portion; blades sublinear-attenuate, strongly U-canaliculate with erect margins mainly when under water stress, distinctly arcuate with recurved apical portion, 20–38 cm long, 1.5–2.5 cm wide near the base, green or bronze to reddish colored, opaque, in the same population the green specimen densely white lepidote at the base only and glabrous toward the apex on both sides, and the bronze and reddish specimens densely and coarsely white lepidote abaxially with the trichomes obscuring the color of the blades, and densely to sparsely white lepidote adaxially with trichomes disposed mainly along the intercostal zones and not completely obscuring the color of the blades, nerved on both sides, apex long acuminate-caudate, pungent-spinescent, margins glabrous, densely (at the base) to sparsely (toward the apex) spinose, spines narrowly triangular to acicular, 1–3 mm long, the basal ones 1–3 mm apart, the remaining ones 5–7 mm apart, straight to prevailingly retrorse-uncinate, castaneous, glabrous. Peduncle erect, 10–34 cm long, 2–3 mm in diameter, glabrous, green to dark purplish-wine; peduncle bracts erect, stramineous, distinctly nerved, with a central protruded longitudinal nerve toward the apex and appearing carinate, densely white lepidote to glabrous, with a suborbicular base 3–5 × 3–5 mm, and a long acuminate-caudate blade, 5–18 × 2–3 mm, exceeding (basal ones) to shorter than the internodes, margins minutely spinulose. Inflorescence erect, 6–11 cm long, densely flowered, rachis slightly flexuous, terete, orange toward the apex, glabrous, 1.5–2.5 mm in diameter, internodes 5–12 mm long; floral bracts subtriangular-ovate, acuminate, ecarinate, nerved, stramineous, glabrous, thin in texture, 4–8 × 3–4 mm, suberect to subspreading with the flowers, distinctly shorter than the sepals, margins inconspicuously denticulate to entire. Flowers 11 to 18 in number, 14–15 mm long, subspreading at anthesis and suberect secund afterwards, odorless; pedicels inconspicuous, stout, 2–3 mm long, ca. 5 mm in diameter at the apex; sepals ovate, rounded and inconspicuously apiculate, symmetric, ecarinate, ca. 6 × 5 mm, orange to yellowish-orange, glabrous, entire; petals symmetric, broadly spathulate from a narrower base, apex truncate and inconspicuously emarginate, connate at the base for ca. 1.5 mm to form a common tube with the filaments, ca. 11 × 9 mm, ecarinate, orange to yellowish-orange, suberect at anthesis and forming a subtubular corolla ca. 6 mm in diameter at the apex; stamens about equaling the petals; filaments complanate, yellowish, connate at the base for ca. 1.5 mm and free above the common tube with the petals; anthers sublinear, ca. 4 mm long, base distinctly bilobed, apex apiculate, slightly recurved near the apex, fixed at the base; pistil ca. 7 mm long, hidden by the filaments; stigma conduplicate-spiral, blades orange; style ca. 1.5 mm long, yellowish; ovary ovate, ca. 4.5 mm long, ca. 2 mm in diameter, yellowish. Capsules broadly fusiform, 12–15 × 8–10 mm, greenish at early development to dark greenish-castaneous afterwards; seeds suborbicular, flat, ca. 3.5 × 3 mm, castaneous.

Distribution and habitat:— Dyckia pottiorum is known from the type collection only, where it grows in full sun, forming small groups of plants on shallow soils accumulated on flat or slightly inclided rocky outcrops. The area supports Cerrado vegetation with sparse shrubs to small trees varying according to the soil depth.

Etymology:—The name chosen for this new species honors the botanists Arnildo Pott and Vali Joana Pott of the Programa de Pós Graduação em Biologia Vegetal, Universidade Federal de Mato Grosso do Sul, for their so valuable contribution to the knowledge of the flora of Central Brazil.

Additional specimens examined (paratypes):— BRAZIL. Mato Grosso do Sul: Corguinho , road MS 080 , Corguinho to Rio Negro , km. 99, 493 m elevation, 19° 43’ 53.8” S 54° 54’ 45.2” W, 16 September 2011, Leme et al 8578 ( RB); ibidem, 8580 ( RB) .

Observations:—Like most of the Bromeliaceae members, Dyckia species usually have leaves spirally arranged in rosettes. Dyckia estevesii Rauh (1987: 918) , D. mauriziae Esteves & Hofacker (2011: 39) , and D. mirandiana Leme & Miranda (2009: 75) are exceptions, because their leaves are distichously disposed and flabellate, with the plants being more or less prostrate. However, despite sharing the same leaf conformation, these species are not at all similar when considering flower morphology. Since many species of Dyckia are known by fragmented type specimens, in which leaves or leaf-rosettes are not completely documented, it may be possible that other unrelated taxa have that same unique flabellate shape. So, the discovery of a new species, like D. pottiorum , with such an unusual leaf disposition requires a carefull evaluation in order to avoid the almost irresistible tendency to only compare it with known species that share such a distinctive attribute.

Dyckia pottiorum is morphologically related to D. burchellii Baker (1889: 131) and D. coximensis L.B.Sm. & Reitz (in Smith 1970: 282), both from the states of Goiás and Mato Grosso do Sul, respectively, Central Brazil. When compared to D. burchellii , this new species differs by the leaf blades sparsely spinose toward the apex (vs. entire), inflorescence densely flowered (vs. laxly flowered), and basal floral bracts distinctly shorter than the sepals (vs. longer than the flowers). On the other hand, D. pottiorum can be distinguished from D. coximensis by the basal floral bracts distinctly shorter than the sepals (vs. equaling the sepals), flowers more numerous (11 to 18 vs. ca. 6 in number), ecarinate sepals (vs. only the posterior ones carinate), and by the subtubular corolla (vs. campanulate).

The known population of D. pottiorum is composed of bronze colored to reddish-leafed specimens intermingled with green-leafed ones. The flower color also varies naturally within populations from orange to yellowish-orange.

Figures

FIGURE 10. Dyckia pottiorum. A–E (Leme et al. 8579). A. General view of the habitat. B. Population at type locality. C. Habit. D.Inflorescence. E. Detail of leaf arrangement. F–G (Leme et al. 8578). F. Detail of the habit. G. Leaf arrangement. (Leme et al. 8579) H. Flowers.

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.