Autor: Glass & Fitz Maurice
Genus honouring George Sebastian Hinton (1949-), Mexican botanist who discovered the taxon (see portrait above, ccourtesy of George S. Hinton).
Monospecific genus of solitary plants (except when the apex has been damaged), globose to subglobose, becoming columnar with age, with bluish-green epidermis. Deep and well-defined ribs, not tuberculate. Areoles at first woolly at the apex, becoming glabrous with age. Spines few (0-3), slightly curved, more or less papery, soon deciduous.
Flowers diurnal, self-sterile, apical, funnel-shaped, intense pink to magenta. Fruits hidden in the apical wool, naked, with irregular dehiscence, floral remains persistent. Seeds small, rough, black, shiny.
The monotypic genus Geohintonia grows in very large colonies, but in a limited area, in the state of Nuevo-Leon in Mexico, together with Aztekium hintonii and other cacti and succulents, at approximately 1200 m in altitude, on steep hills or cliffs of pure gypsum.
Currently only one recognised species:
– Geohintonia mexicana* Glass & Fitz Maurice 1991