Aeschynomene L. (Fabaceae)

Aeschynomene comprises three species in North Carolina, including one exotic from South America (A. rudis). Only Aeschynomene virginica is listed (Fed T, S1 G2). It is one of only three federally listed annuals in North Carolina, the other two being Amaranthus pumilus and Ptilimnium viviparum.

Federally listed taxon
Aeschynomene virginica (Fed T, State T | S1 G2)

Habitat. Bare to sparsely vegetated substrates in intertidal zone where flooded twice daily, marsh edges, or ditches.

Range. Endemic to the southeastern United States.

Additional resources. NHP | USFWS | Recovery plan

Key to Aeschynomene in North Carolina

Key adapted from Weakley (2008). Photos by Krings, unless otherwise indicated. Line drawings from Britton & Brown (1913). Photos of A. rudis are courtesy of Fred Hrusa (CDFA) and cannot be re-used without his express written permission. Maps courtesy of USDA PLANTS and the North Carolina Natural Heritage Program.

1. Mature fruit stipe ≥ 12 mm long; fruit segments 5–7 x 4.5–6.5 mm; paired bracts subtending each flower toothed (rarely entire); standard greenish-yellow with distinct dark-red veins...A. virginica*

1'. Mature fruit stipe 4–8 (–10) mm long; fruit segments 4–6 x 3.5–6 mm; paired bracts subtending each flower toothed or entire; standard pale orange or reddish-orange, the veins usually indistinct...2.

2. Paired bracts subtending each flower entire (rarely toothed); fruit segments 4–5 x 3.5–5 mm...A. indica

2'. Paired bracts subtending each flower toothed (rarely entire); fruit segments 5–6 x 5–6 mm...A. rudis


Similar species

Chamaecrista fasciculata (Fabaceae; shown below) may also occur in ditches in the areas from which species of Aeschynomene are known. In flower, the caesalpinoid, yellow corolla of C. fasciculata could not be confused even at a glance for the papilionoid corolla of Aeschynomene. However, when in fruit, closer examination is warranted. While the fruits of Aeschynomene typically exhibit glandular trichomes (at least when young), the fruits of C. fasciculata exhibit only eglandular trichomes. Vegetatively, C. fasciculata is most easily distinguished by the presence of a petiolar gland (absent in Aeschynomene).

Chamaecrista fasciculata
Habit of Chamaecrista fasciculata (Photo: Krings)
Chamaecrista fasciculata
Leaf of Chamaecrista fasciculata (Photo: Krings)
Chamaecrista fasciculata
Leaf of Chamaecrista fasciculata (Photo: Krings)
Chamaecrista fasciculata
Leaf of Chamaecrista fasciculata. Note petiolar gland. (Photo: Krings)
Chamaecrista fasciculata
Detail of petiolar gland of Chamaecrista fasciculata (Photo: Krings)
Chamaecrista fasciculata
Fruit of Chamaecrista fasciculata (Photo: Krings)
Chamaecrista fasciculata
Fruit detail of Chamaecrista fasciculata. Note that trichomes are eglandular (Photo: Krings)