Lotus subbiflorus
Varied. Ci. 2(4): 213. 1805.
Herbs annual, 7–25[–100] cm, hirsute; taprooted. Stems erect to decumbent, solid, not succulent. Leaves 8–15[–25] mm; rachis 2–4 mm; leaflet blades: basal 2 ovate, terminal 3 obovate to oblong or lanceolate, 5–10[–20] × 1–5.5[–8] mm, length 2–4 times width, apex acute to obtuse, often mucronate. Peduncles ascending to declined, 0.7–3[–15] cm. Inflorescences (1 or)2–4(–6)-flowered; bracts 3-foliolate. Flowers 5.5–7[–10] mm; calyx 3.3–4.7 mm, lobes not recurved in bud, linear, 2.5–3.2 mm, longer than tube, tube hirsute; petals yellow, turning reddish, 5–6.7[–10] mm, wings shorter than angled and beaked keel. Legumes brown, cylindric, 7–10 × 0.7–1.2 mm, not or partially septate. Seeds 8–10, brown to greenish brown, ± mottled, globose to round-oblong, 1 mm, smooth. 2n = 12, 24 (Europe).
Phenology: Flowering summer.
Habitat: Moist roadside ditches.
Elevation: 40–200 m.
Distribution
Introduced; Oreg., w Europe, n Africa (Algeria), Atlantic Islands (Azores), introduced also in South America (Argentina), Pacific Islands (Hawaii, New Zealand), Australia.
Discussion
Lotus subbiflorus is easily distinguished by its very hirsute foliage and its sharply angled, beaked keel that is longer than the wings.
The introduced Lotus subbiflorus was collected first in 2009 at four locations in Curry County. The taxon is introduced elsewhere in the world, reported under the names L. hispidus, L. subbiflorus, or L. suaevolens (R. P. Randall 2002); when plotted worldwide, reports of L. hispidus and L. subbiflorus have similar overall distributions. Thus, it seems that in areas outside the native range, only a single entity is present that should be called L. subbiflorus.
The name Lotus hispidus Desfontaines (1804) was considered an invalid name by T. E. Kramina (2006). Kramina, however, appears to have been unaware of the subsequent validation of the name by de Candolle: L. hispidus Desfontaines ex de Candolle in J. Lamarck and A. P. de Candolle, Fl. Franç. ed. 3, 4: 556. 17 Sep 1805. The exact publication date of the name L. subbiflorus by Lagasca, however, is not known, but it may have been late in 1805 because Varied. Ci. 2(4) has 6 numbers (19–24) that were issued in 1805, and the name was published in number 22. Without an exact date for that publication, it is not possible to decide which name has priority, and currently the name L. subbiflorus is adopted for the species.
Selected References
None.