Euploca humilis (Linnaeus) Feuillet (2016: 104)

Melo, José Iranildo Miranda De, Paulino, Renan Da Cruz, Oliveira, Regina Célia De & Vieira, Diego Daltro, 2018, Flora of Rio Grande do Norte, Brazil: Boraginales, Phytotaxa 357 (4), pp. 235-260 : 248-249

1.1. Euploca humilis (Linnaeus) Feuillet (2016: 104) .

≡ Tournefortia humilis Linnaeus (1753: 141) .

= Heliotropium ternatum Vahl (1794: 21) .

Common names: alecrim bravo, fedegoso.

Subshrubs, erect to semiprostrate, when erect presenting up to 60 cm tall; stems cinereous to pale brown, tomentose to sericeous, trichomes whitish. Leaves alternate, sessile to petiolate; lobe 0.7–3 × 0.1–0,5 cm, chartaceous, narrowly-elliptic, lanceolate to linear, base acute, apex acute, margin revolute, adaxially sparsely to densely sericeous, abaxially tomentose; venation reticulodromous; petiole 1–2 mm long, sericeous. Inflorescences 1.5–15 cm long, terminal and axillary, congested at apex, sericeous; bracts 2.5–2.7 × 0.3–0.4 mm, narrowly-elliptic, inconspicuous, sericeous, margin ciliate; peduncle 1.3–2 cm long. Flowers 3–5 mm long, subsessile; calyx deeply lobed, lobes 2–2.5 mm long, slightly unequal, oval-elliptic to lanceolate, sericeous both inside and outside; corolla 3–4.5 mm long, tubular-hypocrateriform, white, throat yellow, sericeous externally; tube 2–3 mm long, constricted near the base and at throat; lobes 1.5–2 mm long, obovate. Stamens subsessile, inserted at the constriction portion of the tube ca. 1 mm from the base, enveloping the stigma; anthers ca. 1 mm long, ovate, base cordate, apex long-caudate, coherent. Ovary 0.3–0.4 mm long, globose, 4-locular, glabrous; style ca. 0.5 mm long; stigma narrowly conical, 0.6–0.8 mm long, apex split into two lobes; 1 ovule per locule. Schizocarp ca. 1.5 mm diam., globose; nutlets 4, trigone, densely hirsute; seeds ca. 1 mm long, orbicular.

Notes:— Characterized mainly by the subshrubby habit, cinereous to pale brown stems, inflorescences with narrowly-elliptic inconspicuous bracts, and globose fruit with four densely hirsute nutlets. Illustrations of this species can be found in Melo & Semir (2010).

Geographic distribution:— Occurs in Mexico, Central America , the Antilles, Guyana, Venezuela, and Brazil ( Frohlich 1981). In Brazil in the Northeast, Midwest, and Southeast regions ( Melo & Semir 2010). C5, D5, E1.

Habitat:— Caatinga, riparian forest, in rocky soils.

Phenology:— Collected in flower and fruit in April.

Selected material examined:— BRAZIL. Rio Grande do Norte: Currais Novos, 06º09’40”S, 36º36’15”S, April 1981, fl. fr., G.F. C. Lima 95 (MOSS). Felipe Guerra, 05º36’05”S, 37º41’33”W, April 2008, fl. fr., R.C. Oliveira et al. 2122 (MOSS). São Tomé, 05º59’30”S, 36º13’30”W, April 1980, fl. fr., O.F. Oliveira et al. 395 (MOSS). Serra Negra do Norte, 06º33’57”S, 37º16’38”W, April 2007, fl. fr., J.I.M. Melo et al. 594 (MOSS).