Bacopa scabra (Benth.) Descole & Borsini (1954: 137) var. scabra

Sosa, María De Las Mercedes, Moroni, Pablo & O’Leary, Nataly, 2018, A taxonomic revision of the genus Bacopa (Gratioleae, Plantaginaceae) in Argentina, Phytotaxa 336 (1), pp. 1-27 : 16-19

10. Bacopa scabra (Benth.) Descole & Borsini (1954: 137) var. scabra . Fig. 10 .

≡ Herpestis scabra Bentham (1836: 57) ≡ Monniera scabra (Benth.) Kuntze (1891: 463) .

Type:— BRAZIL. Rio Grande do Sul, J. Tweedie 177 (lectotype K 000533413! [designated by Souza & Giulietti 2009: 40].

= Bacopa hassleriana Chodat & Hassler (1904: 289) .

Type:— PARAGUAY. Carimbatay, E. Hassler 5820 (lectotype G 00229876! [designated here], isolectotypes BM 000098485!, G 00229875!, G 00229877!, G 00229878!, K 000533458!, NY 00067874!, P 00634488!).

Herbs, perennial 15–40(–100) cm tall, erect, branched, slightly strigose or puberulous. Leaves opposite, sessile or with a brief petiole, blade ovate, 17–32 × 4–12 mm, apex acute, base acute, margin slightly serrate, hispid strigose on abaxial surface. Flowers axillary, solitary or 2 per axil, pedicel 4–8(–13) mm long, densely strigose, bracteoles two, linear, 3–4 mm long, strigose. Calyx 5-lobed, the external dorsal lobe ovate to oblong, 3–4.5 × 2–2.5 mm, apex acute, base truncate, the two lateral lobes ovate, 4 × 2 mm, apex acute, base acute, puberulous, the two internal lobes linear, 2.5–4 × 0.5–1 mm, apex acute, puberulous. Corolla lilac, tube 5–6 mm long, puberulous; stamens 4; ovary glabrous, style entire, stigmatic apex bilobed. Capsule globose, apex rounded, 4–5 × 3.5–4 mm.

Distribution and habitat:—Native to South America, it grows in Brazil, Paraguay and northeastern Argentina, between sea level and 1000 m elev.

Nomeclatural remarks:— Chodat & Hassler (1904) described Bacopa hassleriana based on a collection made by E. Hassler in Paraguay. Four sheets belonging to this collection were found at G where Hassler’s type material from Paraguay is kept ( Stafleu & Cowan 1979). Thus, the specimen showing the best quality of preservation of the important diagnostic features of the taxon is here chosen as lectotype of the name (Art. 9.17).

Taxonomic remarks:— Bacopa scabra var. scabra is similar to B. paraguariensis (see remarks under this last).

Selected specimens examined:— Corrientes: Capital, 6 Apr 1974, Schinini 8706 (CTES). Chaco: Primero de Mayo, Col. Benítez, 20 Apr 1965, Schulz 15018 (CTES). Misiones: Iguazú, Denis s.n. (LIL 70166).

Figures

FIGURE 10. Bacopa scabra var.scabra. A. Plant aspect. B. Detail of node. C. Flower.D. Corolla opened, showing stamens. E. Bracteoles. F. Gynoecium. G. Dorsal lobe, external view. H & I. Lateral lobes, external views. J & K. Internal lobes. L. Fruiting calyx (from Schinini 8706, CTES).