Acritopappus stenophyllus Bautista, Rodr.Oubiña & S. Ortiz, 2017

Bautista, Hortensia P., Rodríguez-Oubiña, Juan & Ortiz, Santiago, 2017, Two new species of the Brazilian endemic genus Acritopappus (Compositae, Eupatorieae) from Chapada Diamantina, Bahia State, Phytotaxa 311 (1), pp. 22-28 : 25-27

Acritopappus stenophyllus Bautista, Rodr.Oubiña & S. Ortiz , sp. nov. ( Fig. 2 )

Acritopappus stenophyllus is rather similar to A. confertus but mainly differs by its shrubby habit, glandulose branches, much narrower leaves (0.7–1.8 cm) with glandulose petioles, capitula often isolate or grouped in pairs, and florets with longer corollas (3.3–3.6 mm). By contrast the latter often has an arboreal habit, eglandulose branches, broader leaves (2–6 cm) with eglandulose petioles, capitula grouped in glomerules and florets with shorter corollas (2.7–2.9 mm).

Type: — BRAZIL. Bahia State: Municipality of Mucugê, near the road between Mucugê and Piatã, 28.4 km from Mucugê, after Boninal , in campos gerais type of vegetation, 1100 m, 12°58’16’’S, 41°32’28’’W, 2 September 1997, H. P. Bautista & J. Rodríguez-Oubiña 2188 (holotypus: HRB!; isotypi: ALCB!, K!, NY!, P!, SANT!) .

Shrub up to 1.70 m high, often scarcely branched at the upper part of the stem. Branches erect-patent, often opposite, subcylindrical, striate, with eglandular, pluricellular, uniseriate, and glandular hairs; internodes 1.5–6 cm long. Leaves entire, opposite, erect-patent, petiolate; petioles 0.5–1.4 cm, striate, not conspicuously enlarged at base nor fused to petiole of opposite leaf, with glandular hairs; lamina 6–14 × 0.7–1.8 cm, narrowly lanceolate to narrowly elliptic, conduplicate, arcuate, green at the field, chartaceous, viscid or not, pinnately nervate; margins entire to crenate, base acute, apex long acuminate to caudate; adaxial face with ± abundant glandular and scarce eglandular hairs; abaxial face with glandular hairs, venation prominent. Capitula isolate or grouped in pairs, arranged in short corymbs, peduncles opposite or alternate, striate, with ± abundant glandular and scarce eglandular hairs, sparsely bracteate, bracteae 3–4 mm long, narrowly lanceolate, acute, with glandular hairs, capitula sessile, rarely in short pedicels. Capitula homogamous with 6–9 florets; involucres 3.5–4.5 × 3.5–4 mm, cylindric, with 6–9 phyllaries in 2–3 series; phyllaries 3–4 × 0.5–0.8 mm, elliptic, green, margins scarious, ciliate, apex acute, base acute to truncate, eximbricate; receptacle inconspicuous, flat, paleaceous, paleae 1–3, 3–4 × 0.2–0.3 mm, flat, elliptic to oblanceolate, margins scarious, ciliate, apex and base acute. Florets hermaphrodite; corolla tubular, 3.5–3.6 × 0.8–1.2 mm, with sparse, stipitate glandular trichomes, pink to lilac; corolla tube 2.8–3 × 0.6–0.9 mm; lobes 0.5–0.6 mm long, patent to ascending, apex acute, with short papillae located internally in upper part; anthers 1.5–1.6 mm long, apical appendage 0.5 × 0.4 mm, ovate, longer than wide, with acute apex, anther base rounded, collar cylindric; style ± 5 mm long, glabrous; style branches ± 2.5 mm long. Cypsela 1.8–2 × 0.4–0.5 mm, black, prismatic, base often asymmetric, glabrous, 5-ribbed, distances between ribs unequal; carpopodium very slightly lateral (asymmetrical); pappus 0.1–0.5 mm long, coroniform, sometimes inconspicuous, to aristate.

Etymology: —The specific epithet refers to its very narrow leaves.

Phenology: —The material indicates that this species is in flower and fruit from February to September but it might have flowers and fruits all year long, like other species of Acritopappus (i.e. A. confertus ).

Geographical distribution and ecology: — Acritopappus stenophyllus is present at altitudes ranging between 900 and 1400 m a.s.l. in southern Chapada Diamantina (Bahia State) were it colonizes campos gerais. This is a type of vegetation covering large, flat to gently rolling reliefs with poor, sandy and shallow soils dominated by grasses, smallsized shrubs and acaulescent palms ( Zappi et al. 2003). This type of vegetation currently suffers great devastation as a result of the implementation of megaprojects of mechanized and irrigated agriculture for cultivation of sweet potato, cabbage and cassava.

Additional specimens examined: — BRAZIL. Bahia State: Municipality of Palmeiras, 25 km from Mucugê on the road to Palmeiras , in campos gerais type of vegetation, 930 m, 12º41’22”S, 41º34’15”W, 30 August 1997, H. P. Bautista & J. Rodríguez-Oubiña 2120 ( HRB!) ; Municipality of Piatã, João Teixeira, Porteiras Farm , in campos gerais type of vegetation, 1420 m, 13º01’53”S, 41º54’51”W, 2 August 1997, H.P. Bautista & J. Rodríguez-Oubiña 2214 ( HRB!) ; Municipality of Piatã, Três Morros, near Porteiras Farm , in campos gerais type of vegetation, 1390 m, 13º03’44”S, 41º53’03”W, 2 September 1997, H.P. Bautista & J. Rodríguez-Oubiña 2221 ( HRB!) ; Municipality of Piatã, near Serra das Palmeiras , 13 km from Pousada Arco Iris , in campos gerais type of vegetation, 13º07’58”S, 41º51’35”W, 28 August 1998, H.P. Bautista & S. Ortiz 2869 (HRB 41136!, SANT!) ; Municipality of Piatã, Serra da Tromba, “gerais de Inubia”, 22–26 km from Catolés , in campos gerais type of vegetation, 1400 m, 10 March 1992, B. Stannard, W. Ganev & R.F. Queiroz H51850 (HRB!, K!) ; Municipality of Rio de Contas, Água Quente, Pico das Almas , 1400 m, 19 February 1987, R.M. Harley, J.R. Pirani, B.L. Stannard, I. Cordeiro & C. Kameyama 24431 (HRB 36510!, SANT!) .

Discussion: —The species most morphologically similar to A. stenophyllus seems to be A. confertus , the most widely distributed species in the genus, distributed along the NE region of Brasil including Bahia, Ceará, Pernambuco and Sergipe States. Within the group of species with less than 10 florets per capitulum, A. catolesensis Hind & Bautista in Bautista & Hind (2000: 950) from southern Chapada Diamantina (Bahia State) and A. pereirae Bautista et al. (2011: 227) from Serra do Cabral (Minas Gerais State) also present some morphological similarities to A. stenophyllus . Main differences between these four taxa are shown in Table 2.

Figures

FIGURE 2. Acritopappus stenophyllus: A. Floriferous branch; B. Leaf; C. Detail of the inflorescence; D. Capitulum; E. Median phyllary; F. Floret; G and G1. Cypselas with aristate and coroniform pappi.A–G1: Bautista & Rodríguez-Oubiña 2188 (SANT). Drawing by Rafael Salvador and Luis Orellana.