Crotalaria irwinii Windler & S.G. Skinner (1982:204)

Flores, Andréia Silva & Tozzi, Ana Maria Goulart De Azevedo, 2018, A synopsis of the genus Crotalaria (Leguminosae) in Brazil, Phytotaxa 346 (1), pp. 31-58 : 41

14. Crotalaria irwinii Windler & S.G. Skinner (1982:204) . ( Fig. 3b ).

Type: — BRAZIL. Goiás: outcrops & rocky slopes, ca. 24 km S of Paraiso , ca. 600 m, 24 March 1968, H.S. Irwin H. Maxwell & D.C. Wasshausen 21747 (holotype: NY!; isotypes: BALT not seen, K000500570 digital image!, UB!)

Subshrubs or shrubs 1–1.5 m high; branches finely pubescent or puberulous, stem not ribbed; internodal stem wings decurrent at the junction of the branches and the main axis, broad at the top, 36–66 × 8–13 mm, elliptic. Leaves simple, blades obovate or wide elliptic, 6.5–9.5 × 4.5–5.5 cm, base cuneate, glabrescent above and puberulous beneath; stipules absent. Inflorescence a raceme, 35–37 cm long, appearing terminal; peduncles 4–8 cm long. Flowers 15–20, pedicels 10–13 mm long; bracts 4–7 × 1–2 mm, elliptic- lanceolate, persistent; bracteoles 4–5 × 1–2 mm, elliptic- lanceolate, persistent; calyx 20–25 mm long, deeply divided into 2 lips, puberulous; corolla yellow; the standard petal 2–2.5 × 2 cm; wing petals 1.9–2.1 cm long; keel petals 1.9–2 cm long, twisted; ovary 6 mm long, glabrous, subsessile; style geniculate. Legumes and seeds not seen.

Distribution and Ecology: — Crotalaria irwinii is a rare species found in Chapada dos Veadeiros region and North of Tocantins state. The taxon occurs in the borders of gallery forests, and rocky outcrops and slopes.

Specimen studied: — BRAZIL. Goiás: Alto Paraíso de Goiás, 23 March 1968, Irwin et al. 21657 ( UB) ; Tocantins: Guaraí. Ca. 15 km S.E. of Guaraí on road to Tupirama. [in label: “ 12 km S of Guara ”], 21 March 1968, Irwin et al. 21607 ( NY) .

Figures

FIGURE 3. Habit of (a) Crotalaria holosericea Nees & Mart. (Flores et al. 757, UEC), (b) Crotalaria irwinii Windler & S.G. Skinner (Irwin et al. 21657, UB), (c) Crotalaria laeta Mart. ex Benth. (Flores et al. 793, UEC), (d) Crotalaria longirostrata Hooker & Arn. (Carvalho 34, VIC). Scale bar: 5 cm.