Cuphea dryadica M.G.Facco & T.B.Cavalc., 2022

Facco, Marlon Garlet & Cavalcanti, Taciana Barbosa, 2022, Novelties in Cuphea (Lythraceae) from Serra do Espinhaço and Serra da Mantiqueira, and a key to the species from Minas Gerais state, Brazil, Phytotaxa 568 (3), pp. 267-276 : 268-270

1. Cuphea dryadica M.G.Facco & T.B.Cavalc. , sp. nov.

Type:— BRAZIL. Minas Gerais: Rio Preto, Serra Negra , Burro de Ouro [approx. -21.970, -43.889], 26 February 2006, Viana & Mota 1976 (holotype CEN [00069660]! , isotype CESJ!) . Figs. 1 , 3 .

Diagnosis:— Cuphea dryadica resembles C. pseudovaccinium Saint-Hilaire (1833: 102) , both classified in C. sect. Euandra subsect. Hilariella , but differs mainly by the leaves with shorter petioles, 0.5–1 mm long, hyphodromous, with slightly marked secondary veins, larger floral tubes, 10–12 mm long, covered by sparse glandular trichomes, <0.5 mm long, on the veins, glabrous between them, and by the two dorsalmost short stamens glabrous versus leaves with longer petioles, 1–4 mm long, pinnately-veined, abaxial surface prominently reticulate, lateral nerves 5–8, floral tubes shorter, 7–9 mm long, covered with short, white eglandular trichomes, and short glandular trichomes, <1 mm long, purple, and the two dorsalmost short stamens villous.

Description:—Subshrubs 50–100 cm tall; xylopodium absent; stems erect, indumentum pubescent, white eglandular trichomes, <0.2 mm long, mixed with sparse glandular trichomes, ca. 0.3 mm long; internodes 0.5–2.5 cm long. Leaves opposite, rarely subalternate, chartaceous to subcoriaceous, petioles 0.5–1 mm long, blades 6–19 × 3–8 mm, elliptic, narrowly ovate to narrowly obovate, apex acute to obtuse, rarely slightly apiculate, base acute to obtuse, margin plane to revolute, glandular-ciliate and sparsely strigose, blades glabrous, sometimes slightly pubescent on the base of main vein in adaxial surface, and sparse glandular trichomes on main vein on abaxial surface; hyphodromous, secondary veins slightly marked, primary veins prominent on the abaxial surface. Racemes frondose to frondosebracteose, compound; bracts similar to leaves. Flowers alternate; pedicels 3–4 mm long, interpetiolar, rarely axillary; bracteoles 0.7–0.9 × 0.6–0.7 mm, broadly ovate to elliptic; floral tubes 10–12 × 2.5–3 mm; spur ca. 2 mm long, obtuse, horizontal to deflexed; outer surface purplish in dorsal region, greenish ventrally, glandular trichomes sparse, <0.5 mm long, on the veins, glabrous between them, base of the tube slightly pubescent; inner surface villous behind the stamens, pilose to villous on the dorsal veins, rarely pilose on the veins of the lower portion of the tube; petals magenta, purple to lilac, ca. 6.5 × 3.2 mm, elliptic; stamens alternately unequal, the 3 antesepalous glabrescent, the two dorsalmost short stamens glabrous, the others villous; vesicles absent, or 6, elongate; pistil 9.5–10 mm long; ovary ca. 3 mm long, glabrous; style ca. 6.5 mm long, glabrous; ovules 3; nectary ca. 1.3 × 1.2 mm, deflexed. Seeds 2.5–2.9 × 2.4–2.8 mm, suborbicular to broadly obovate, apex truncate to obtuse, base obtuse to rounded, margin obtuse to thickened.

Distribution and habitat:— Brazil, in the extreme south of the state of Minas Gerais ( Fig. 3 ); “campo rupestre”, and “campo de altitude”; 930–1470 m elev.

Conservation status:— Cuphea dryadica was categorized as Critically Endangered (CR) B1ab(i,ii,iii), with EOO estimates of 64 km ² and AOO of 16 km ². The species is represented by four collections, three of which located in Serra Negra da Mantiqueira State Park, created in 2018 (Decree with Special Numbering 301, July 04, 2018). Historically, the region has been impacted by anthropogenic fires, pastures for cattle breeding, mining, logging, and Eucalyptus plantations ( Martinelli & Moraes 2013; Salimena et al. 2013). The fourth record, in the municipality of Lima Duarte, is not included in a protection area.

Phenology:—Collected with flowers and fruits in November and February.

Etymology:—The specific epithet is a reference to the Brazilian Phytogeographic Province “Dryades”, the name of the tree nymphs in Greek mythology used by Carl Friedrich Philipp von Martius (1840 –1869) to designate the region that roughly corresponds to the current circumscription of the Brazilian Atlantic Rainforest, where the new species is endemic.

Paratypes:— BRAZIL. Minas Gerais: Lima Duarte, Vilarejo Mogol [-21.745, -43.844], 23 November 2001, Araújo & Valente 157 (CEN!, CESJ); Rio Preto, Serra da Caveira D’anta, Faz. da Tiririca [-21.981, -43.936], 15 November 2003, Salimena-Pires et al. 1145 (CEN!); Rio Preto, Faz. da Tiririca, entre o Rio Preto e Olaria, 21°58’03”S, 43°56’08”W, 23 February 2004, Salimena-Pires et al. 1233 (CEN!).

Notes and taxonomic affinities:— Cuphea dryadica occurs restrictedly in the extreme south of the state of Minas Gerais ( Fig. 3 ) (“Zona da Mata”), Brazil, in the Serra da Mantiqueira complex (Mantiqueira Meridional), in “campos rupestres” and “campos de altitude” under the Atlantic Rainforest domain. Collections are concentrated within the Serra Negra da Mantiqueira State Park, in the municipality of Rio Preto. A single collection is located about 25 km north of Serra Negra, in the municipality of Lima Duarte, near the Ibitipoca State Park.

Cuphea dryadica is morphologically similar to C. pseudovaccinium , both classified in C. sect. Euandra subsect. Hilariella . Cuphea pseudovaccinium is distributed mainly in the Meridional block of the Serra do Espinhaço (central region of the state of Minas Gerais), in “campos rupestres” on sandy soil, with which it is compared in the diagnosis.

Figures

FIGURE 1. A–H. Cuphea dryadica M.G.Facco & T.B.Cavalc. A. Branch; B. Leaf, adaxial surface; C. Leaf, abaxial surface; D. Flower, lateral view, petals not shown; E. Flower, longitudinal-dorsal section, petals not shown; F. Detail of the upper third of the floral tube inner surface, vesicles (arrows) in the region below the stamens shown; G. Pistil with the subtending nectary; H. Seed.A, C, F: Salimena-Pires et al. 1233; B, H: Salimena-Pires et al. 1145; D, E, G: Viana & Mota 1976. Scale bar. A: 5 cm; B–C: 3 mm; D, E, G: 2 mm; F, H: 1 mm.

FIGURE 3. Geographical distribution of Cuphea dryadica M.G.Facco & T.B.Cavalc. and Cuphea venosa M.G.Facco & T.B.Cavalc. (MG = Minas Gerais state). Source: Topodata database (Valeriano & Rossetti 2012); IBGE (2021); SISEMA (2021).