Prosopis reptans

Name and classification

Prosopis reptans Benth. var. reptans
Family Fabaceae, Subfamily Mimosoideae

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

Common names

tornillo

Description

Pods tightly coiled (like a corkscrew) into a cylinder, several of which radiate from the receptacle in a cluster; each cylinder composed of 9–19 coils each 2–4 mm thick, cylinders straight or slightly curved, 2.5–5 cm long, 5–8 mm in diameter. Margins nonundulate. Smooth, puberulent when young, lemon-yellow when ripe; seed chambers not visible. Mesocarp reddish, pulpy, tannic; endocarp easily disintegrates. Seeds oriented longitudinally.

Seeds asymmetrically obovate to slightly oblong in outline, 3.9–5 mm long, 2–3 mm wide, 1–1.6 mm thick, umbo absent, elliptic in cross section. Pleurogram average in size. Lens a dull mound.

Identification considerations

Similar species

Pods of:

Prosopis strombulifera (Lam.) Benth. (Pods have 8–17 coils, puberulous when young.)

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

Argentina, Peru (rare)

General information

Prosopis reptans var. reptans is a low, spiny shrub up to 1 m tall, with underground runners that invade the soil. Its seeds are tightly held in the pods. The two varieties, var. reptans and var. cinerascens, are very closely related morphologically, but helpfully, differ in their geographical distributions; var. cinerascens is found only in Texas and adjoining Mexico.

Seeds

Seeds

lens and hilum of seed

lens and hilum of seed

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