Ecology: Dry open thorn-cactus forest; on rocky soil and trunk and branches of trees (including Chorisia insignis and Prosopis alba). Also found in urban areas on trees, i.e., Santa Cruz de la Sierra. Elevation: 400-1860 m (Bolivia: 400-1860 m, Argentina: 1300 m). Distribution: Arid south central North America (Texas). northern Mexico, southern tropical Andes (Bolivia and NW Argentina), and South Africa.
Distinguishing features of S. chisosa include spatulate leaves (to 2.5 mm long), plane margins, bistratose lamina, with a strong, short excurrent costa that is sharply toothed distally on the back, and small, reduced brood leaves. The only other species likely to be confused with S. chisosa is S. ammonsiana, but that species has a unistratose lamina and only weakly papillose on the back of the distal costa. This species is common within the geographical range.
Las características que diferencian a S. chisosa incluyen las hojas espatuladas (hasta 2.5 mm de largo), márgenes planos, lámina biestratificada, con una costa corto excurrente fuerte que es nítidamente dentada en el envés de la porción distal, y hojas multiplicativas reducidas. La única otra especie que puede ser confundida con S. chisosa es S. ammonsiana, pero esta especie tiene lámina uniestratificada y el envés de la porción distal de la costa es débilmente papilosa.