Herbs from a short, ovoid-fusiform tuber sometimes pro­ducing slender rhizomes or rhi­zomelike caudex branches from apex. Stems procumbent, not twining, lignescent, sparsely to moderately short-strigose, hairs retrorse. Leaflets 1, blade narrowly elliptic to narrowly lanceolate, 25–85 × 4–10(–16) mm, leathery, veins closely reticulate and strongly raised, thickened marginal vein completely encircling entire margin, apex rounded to obtuse, surfaces not glaucous abaxially, glabrous throughout. Inflorescences: flowers solitary, axillary; axis 3–8 mm. Flowers: calyx 5–6 mm, short-strigose; corolla pink to purple, purple-red, or deep lavender, 13–15 mm. Legumes straight, 25–35 × 5–7 mm, short-strigose, hairs closely appressed. Seeds (5–)7–9.

Phenology: Flowering (Feb–)Apr–Oct.
Habitat: Oak-juniper woodlands, blackjack-post oak woods, coastal prairies, sands, sandy loam, gravelly hillsides, ditch banks.
Elevation: 0–200 m.

Distribution

• Generated Map
• Legacy Map

Tex., Mexico (Coahuila, Tamaulipas), South America (Argentina, Brazil, Paraguay, Uruguay).

Discussion

Galactia marginalis is characterized by prostrate stems, glabrous, 1-foliolate leaves with closely reticulate, raised venation and a completely encircling marginal vein, and relatively large, solitary, axillary flowers. The species is known from at least 14 counties, mostly on the Coastal Plain of southeastern Texas.

A. Burkart (1971) described Galactia marginalis var. columbiana Burkart based on a specimen from Cundinamarca, Colombia, that was thought to represent an intermediary between the population of G. marginalis in southeastern Texas and in southern South America. The Colombia collection has subsequently been iden­tified as G. glaucescens Kunth.

Selected References

None.

Lower Taxa

None.