Nelsonia canescens (Lam.) Spreng., Syst. Veg.

Y. F., Deng & Asuncion, C., 2023, Nelsonia canescens (Acanthaceae), a first species and genus record from Peru, Rheedea 33 (4), pp. 376-381 : 377

publication ID	https://doi.org/10.22244/rheedea.2023.33.04.08
persistent identifier	https://treatment.plazi.org/id/E71E283B-FFBB-FFB6-48E2-6C336B65F9F1
treatment provided by	Felipe
scientific name	Nelsonia canescens (Lam.) Spreng., Syst. Veg.
status

Treatment

Nelsonia canescens (Lam.) Spreng., Syst. Veg. , ed. 16, 1: 42. 1824. Justicia canescens Lam., Tabl. Encycl. Meth., Bot. View in CoL 1:41. 1791. Type: Senegal, s.d., Roussillon 53 (holo P-LA [P00435346!]; iso P [P00435347!]). Fig. 1 View Fig

For further synonyms see Daniel and McDade (2014: 27).

Annual, creeping, sprawling, prostrate, or decumbent herbs, 10–20 cm tall. Stems sub-terete, villous, often rooting at nodes. Petiole 0.2–3(–4) cm long, villous; lamina elliptic to ovate, 1.5–6 × 0.8–3 cm, base cuneate, margins entire, apex acute, both surfaces villous, secondary veins 3–7 on each side of midvein. Spikes 1–3 cm long; bracts elliptic, 6–7.5 × 3–4 mm, 5–7-veined. Calyx 5-lobed, abaxial lobe c. 2 × 0.6 mm, apex 2-lobed, adaxial lobe c. 3 × 1 mm, lateral lobes c. 2 × 0.5 mm. Corolla bluish purple or white, externally glabrous; tube cylindric for ca. 1.5 mm, contracted near midpoint then expanded into throat; lower lip c. 2.3 mm long; upper lip c. 2 mm long. Stamens inserted at base of throat; filaments c. 0.5 mm long, glabrous. Ovary glabrous; ovules 4–8 per locule. Capsules c. 5 × 2 mm, 8–16-seeded. Seeds broadly ellipsoid, granulate.

Flowering & fruiting: Flowering from March to May and fruiting from July to August.

Habitat: The species grows in the thicket at the elevation of about 200 m.

Distribution: The species is widely distributed in the tropical regions of the world. In Peru, it is known from departments of Madre de Dios and Ucayali ( Fig. 2 View Fig ).

Specimens examined: PERU, Madre de Dios, Tahuamanu Province, Rio Tahumanu, forest floor herb 0.4 m, floodplain, 24.08.1995, P. Nuñez, J. Terborgh & M. Sanchez 17346 ( USM); Tahuamanu Province , km 65 carretera Iberia-Iñapari, 18 May 1978, F.C. Encarnación 1139 (K) . Ucayali, Purús Province, Purús District, Camino a la quebrada de Esperancilla, 190 m, 16.03.2002, J. Schunke Vigo & J.G. Graham 15081 ( USM) .