Dyckia macedoi L.B. Smith (1952: 195)

Guarçoni, Elidio Armando Exposto, Azevedo, Aristéia Alves De & Costa, Andrea Ferreira Da, 2017, The restablishment of Dyckia oligantha and D. nana (Bromeliaceae, Pitcairnioideae), belonging to the D. macedoi complex, Phytotaxa 306 (1), pp. 49-65 : 56-59

1. Dyckia macedoi L.B. Smith (1952: 195) . Figs. 4 A–D , 5 A–C

Type: — BRAZIL, Minas Gerais: Conceição do Mato Dentro, Serra do Cipó, 15 January 1951, Macedo 2974 (holotype US Photo!).

Plant terrestrial or saxicolous, flowering 15.2–45.3 cm high. Leaves 9–39 in number, rigid, succulent, the basal ones reflexed, the median ones spreading-arcuate to suberect, the upper ones suberect to erect, forming a symmetrical rosette, 4.1–12.3 cm long, 9.8–19.1(–21.8) cm in diameter; sheaths suborbicular, 1.4–2.8 × 0.9–3.4 cm, white to greenish, pale-brown spotted on the upper half abaxially, cinereous lepidote in the upper third abaxially, inconspicuously spinose of brown spines; blades narrowly triangular, 4.4–11.7 × 0.6–1.7 cm, canaliculate, green, densely cinereous lepidote abaxially, trichomes concentrated between the ribs and not obscuring the leaf color in between, glabrous adaxially, or trichomes slightly or densely concentrates on both surfaces, apex acute, pungent, margins spinose except for the apical third; the basal spines antrorse to patent in the median ones, dark brown, 1–2.2 × 0.4–0.5 mm, 3–6.7(–7.7) mm apart. Inflorescence simple, erect, 13.3–44.5 cm long; fertile part of the inflorescence 2–12.3 cm long; peduncle erect, terete, 9.6–35.1 cm long, 1.3–2.9 mm in diameter, green, except for the orange distal third, glabrous, internodes 6.7–27.9 mm; rachis orange, 1.2–1.5 mm in diameter, glabrous; peduncle bracts shorter than internodes, broadly ovate, acuminate, ending in a spine, the lower ones 0.8–3.7 (9.3) × 0.2–0.6 cm, green, apex densely white lepidote, margins entire, the upper ones 3.6–7.8(–11.2) × 1.8–4.4(–5.5) mm, stramineous, carinate, glabrous, margins ciliate. Floral bracts shorter than the pedicels, 2.9–7.3 × 1.1–5.6(–6.4) mm, orange, broadly ovate, patent, convex, ecarinate, acuminate, ending in a spine, serrulate. Flowers 5–26(–32) in number, polystichously and subdensely arranged, spreading at the anthesis, 1–1.6 cm long; pedicels distinct, orange, 3.4–6.6(–7.8) mm long, glabrous; sepals symmetric, reaching the midpoint of the petals, orange, broadly ovate to elliptic, 3.9–5.8 × 3–6.1(–7.6) mm, apex acuminate or with an inconspicuous apiculus, glabrous, margins ciliate of conspicuous marginal trichomes, entire at the lower third; petals asymmetric, orange, rhombic, 6.1–8.7 × (4.5–) 5.1–7.5 mm, obtuse to retuse, margins entire, glabrous, corolla tubular. Stamens included; filaments pale yellow, linear, 3–6 mm long, connate at the base for 0.7–1.9 mm to form a common tube with the petals, free above it; anthers lanceolate, 2.7–3.1 mm long, acute or with an inconspicuous apiculus, yellow, dorsifixed near the base. Ovary superior part pyramidal, orange, 2.8–4.6 mm long; style orange, 0.4–1.1(–3.3) mm long; stigma, 0.3–0.9 mm long, yellow. Capsules ovoid, dark brown to black, 7–9.9 mm long, 4.2–8.4 mm in diameter, suberect to erect.

Additional specimen examined:— BRAZIL, Minas Gerais: Jaboticatubas, ao longo da rodovia Lagoa Santa— Conceição do Mato Dentro—Diamantina , est. da Usina, 2 November 1972, Joly & Semir s.n. ( SP 144945 ) ; Serra da Lagoa Dourada , 12 February 1996, Forzza 162 et al. ( VIC; SPF) ; Serrinha, Parque Nacional da Serra do Cipó, 18 November 2009, Louzada 153 et al. ( SP). Santana do Pirapama , Serra do Cipó , acesso pela Faz. Inhame , estr. de terra ligando Capela de São José a Santana do Riacho , 18º59’47”S – 43º45’55”W, 5 March 2009, Zappi 1681 et al. ( SPF) ; estr. velha para a mina de manganês, subida da serra, campo de velózias, 1133 m elev., 18º55’26”S – 43º42’24”W, 13 November 2006, Zappi 2343 ( SPF). Santana do Riacho, ao longo da rodovia BH-Conceição do Mato Dentro , estr. da Usina, 21 March 1983, Wanderley 582 ( SP) ; Parque Nacional da Serra do Cipó, Cachoeira da Farofa , 7 September 987, Wanderley s.n. et al. ( SP 221692 ) ; Serra do Cipó, km 110, ao longo da estr. Belo Horizonte-Conceição de Mato Dentro , estr. da Usina, 16 September 1983, Arraes s.n. ( RB 271813 ) ; 3 Km ao norte do Chapéu do Sol, logo abaixo do Km 110, 13 August 1985, Rutchison & Páffaro s.n. ( RB 245075 ) ; Parque Nacional da Serra do Cipó, Serra do Estreito , 883 m elev., 19°21’27”S – 43°36’30”W, 23 May 2011, Guarçoni 1659 & Paixão ( VIC) ; Serrinha , 883 m elev., 19°21’19”S – 43°37’28”W, 23 May 2011, Guarçoni 1654 & Paixão ( VIC) ; Serra do Cipó, MG-10, Km 5, lado esquerdo em direção Alto Palácio , 19º17’26”S – 43º36’00”W, 11 April 2012, Guarçoni 1816 (R) .

Distribution and habitat:— This s pecies is terrestrial and saxicolous in “Campos Rupestres” vegetation, growing on quartz rocky outcrops in graminoid field, at 883 to 1137 m elevation, at Serra do Cipó, Espinhaço mountain range.

Phenology: —Flowering from August to May.

Conservation status:— Although D. macedoi occurs in a Conservation Unit (Parque Nacional da Serra do Cipó), the species was categorized as vulnerable (VU) due to an estimated 30% reduction in size of its population caused by urban growth at Serra do Cipó.

Comments:— The species can be easily distinguished from D. nana and D. oliganta by its symmetric rosettes (vs. asymmetric) and patent flowers (vs. suberect). The specimens collected in the Santana do Pirapama region (D. Zappi 1681 et al. and D. Zappi 2343 et al.) show distinct characters then those found in specimens from the Serra do Cipó population, like the more densely arranged spines (1.5– 1.2 mm vs. 3–6.7 (7.7) mm) and the lower floral bracts longer than pedicels (vs. shorter than pedicels).

The density of leaf trichomes varies according to the habitat and altitude in D. macedoi ( Table 6). Populations may also differ from one another in terms of whether they form clumps or not. Individuals from Serra do Estreito often form clumps , while those from Serrinha and at km 5 of road MG-010 usually remain isolated under the shadows of subshrubs.

Style size also varies in these populations. At Serrinha and km 5 of MG-010, individuals have subsessile stigma and very narrow styles. Additional studies on their reproductive biology are needed for a better understanding of these differences.

soil type.

Figures

FIGURE 4. A–L. Details of species from the Dyckia macedoi complex. A–D. D. macedoi. A. Detail of the leaf margin, showing the size of spines and the distances between them. B. Floral bract. C. Flower. D. Detail of the flower in longitudinal section. E–H. D. nana. E. Detail of the leaf margin, showing the size of spines and the distances between them. F. Floral bract. G. Flower. H. Detail of the flower in longitudinal section. I–L. D. oligantha. I. Detail of the leaf margin, showing the size of spines and the distances between them. J. Floral bract. K. Flower. L. Detail of the flower in longitudinal section. (Illustrations: Reinaldo Monteiro)

FIGURE 5. A–C. Dyckia macedoi. A. Population Km 5 (P1). B. Population from Serra do Estreito (P2). C. Population from Serrinha (P3). D–E. D. nana. D. Flowering. E. Rosette shape and the substrate over which it occurs. (Photo: Elidio Guarçoni)