Autor: (Backeberg) De Haas

“Echlnopsls with bristles”, because the genus has a floral tube covered with characteristic bristles.
A monotypic genus of small plants with a short life cycle (3-5 years, not much more), usually solitary (sometimes branched), with a short, thick taproot and fine secondary roots. Stem cylindrical, strongly pigmented, brownish or purplish green towards blackish. 11-12 low, straight ribs, areoles covered with white wool. 9-14 straight radial spines, 1 longer and stiffer central spine, finely pubescent.
Flowers nocturnal, self-fertile, appearing around the apex, closely funnel-shaped, with a very long and fine scaly floral tube, covered with hairs and bristles, petals acuminate, white, strongly scented, pollinated by moths with a long proboscis (Manduca sexta). Fruits fusiform (spindle-shaped), longitudinally dehiscent, drying when ripe, floral remains persistent. Seeds globose more or less elongated, dull, tuberculate, dark brown, covered with mucilage.
The monotypic genus Setiechinopsis grows in an atypical area for cacti: saline areas, brackish lands, under low shrubs (Atriplex), in grasslands, at the foot of mountains, from 200 m up to 1250m in altitude.
Argentina (Catamarca, La Rioja, Mendoza, San Juan, San Luis, Santiago del Estero).

Currently only one recognised species:
– Setiechinopsis mirabilis* (Spegazzini) De Haas (1940)

References: "TAXONOMY of the CACTACEAE" -  ISBN 978-84-617-3692-8 (Vol. 2)