Strophostyles leiosperma (Torr. & A.Gray) Piper

Nomenclature and Taxonomic Placement

Strophostyles leiosperma, commonly called slickseed fuzzybean, smoothseed wildbean, or small-flower wildbean, is a species of herbaceous vining legume native to central to western United States.

Distribution Range

Its distribution extends west to Colorado and New Mexico, east to Louisiana, south to Mexico, and north to Minnesota.

Genus Distinguishing Features

It can be most easily distinguished from the other two species in the Strophostyles genus by the dense covering of small silky hairs on its leaves and pods, and small pea-shaped flowers that have a highly reduced keel, which is mostly hidden by the wing petals.

Growth Habit

This plant grows as an annual or a short-lived perennial.

Relative Size

Overall, S. leiosperma is a smaller, more diminutive plant than its closely related species, with all parts tending to be smaller.

Leaflet Characteristics

Its leaflets are typically thin, rarely lobed, and never deeply lobed.

Seed Characteristics

Unlike other Strophostyles species, its seeds rarely have a waxy, hairy covering.

Habitat Preference

This species tends to grow in drier sites.

Etymology of Specific Epithet

Its specific epithet leiosperma translates to "smooth seed."

Reproductive Trait

Of all Strophostyles species, S. leiosperma is the most likely to be capable of self-fertilization.