Prosopis strombulifera

Name and classification

Prosopis strombulifera (Lam.) Benth.
Family Fabaceae, Subfamily Mimosoideae

NOTE: Only ten seeds of Prosopis strombulifera were available for examination. Therefore, the description and images in this fact sheet may not be representative of this species’ seeds.

Common names

Argentine screwbean

Description

Pods tightly coiled (like a corkscrew) into a cylinder with 8–17 coils each 3–5 mm thick, cylinder straight or slightly curved, 1.5–5.2 cm long, 6–10 mm in diameter. Margins nonundulate. Puberulous when young, lemon-yellow when ripe, veins obscure; seed chambers not visible. Mesocarp pulpy, tannic, reddish; endocarp easily disintegrates. Seeds oriented longitudinally.

Seeds usually obovate in outline, (3.1)4.2–5.5 mm long, 2.2–4 mm wide, 1–2 mm thick, umbo absent, elliptic in cross section. Pleurogram average in size. Lens a mound.

Identification considerations

Similar species

Pods of:

Prosopis reptans Benth. var. reptans (Pods have 9–19 coils.)

Prosopis reptans var. cinerascens (Gray) Burkart (Pods have 9–12 coils.) (non-FNW)

Prosopis pubescens Benth. (Pods have 8–24 coils, puberulous or almost glabrous.) (non-FNW)

Distribution

native to Argentina, Chile, Peru; also found in the United States

Habitat

arid and semi-arid regions, sandy, rocky soils, disturbed places below 50 m

General information

Prosopis strombulifera is a spiny shrub up to 3 m tall. This species often forms dense stands, reproducing vegetatively by long, spreading lateral roots from which new shoots develop. Accidentally introduced to California as an experimental desert rangeland plant. Some infestations in the Sonoran Desert have been eradicated. In Chile, the pods are used as a remedy for toothache, and the roots contain a brown dye used for tanning. The seeds are tightly held, but are dispersed by livestock that eat the sweet pods.

seeds

seeds

lens and hilum of seed

lens and hilum of seed

pods

pods

pods

pods

A, pod; B, seed; C, longitudinal section of seed showing embryo; D, transection of seed; drawing by Lynda E. Chandler

A, pod; B, seed; C, longitudinal section of seed showing embryo; D, transection of seed; drawing by Lynda E. Chandler