Sclerocactus

S.L.Welsh & K.H.Thorne

(Engelm.) D.R.Hunt

K.D.Heil & J.M.Porter

K.D.Heil & J.M.Porter

A cactus of western Colorado described in 2024 from northern populations previously assigned to Sclerocactus glaucus. Its distinctness was revealed by consistent genetic, geographical and morphological differences, and its restricted distribution draws attention to preserving variation in individual populations.

A species of western Colorado whose boundaries were clarified by comparing geography, plant structure and thousands of DNA markers. Present-day Sclerocactus glaucus includes the populations of Grand Valley and the Gunnison River valley, while the northern populations in its former circumscription make up S. dawsoniae.

(D.Donati & Zanov.) Lodé

(Engelm.) N.P.Taylor

(Parry ex Engelm.) N.P.Taylor

(Hester) N.P.Taylor

(Rose) Lodé

A small cactus of the clay badlands of southwestern Colorado and northwestern New Mexico. Twenty years of observations revealed its slow maturation from seed, its ability to regrow after damage and the strong influence of beetle larvae on population structure.

Hochstätter

A small cactus with flexible, flattened spines resembling dry blades of grass. Confirmation of its occurrence in Mexico combined nature photography, field research and herbarium documentation, extending the species' known range into Chihuahua.

Clover & Jotter

(García-Mor., Gonz.-Bot. & Rodr.González) M.H.J.van der Meer

(Engelm. & J.M.Bigelow) Britton & Rose

(Engelm.) L.D.Benson

(Salm-Dyck) N.P.Taylor

(L.D.Benson) K.D.Heil & J.M.Porter

(Engelm.) D.Woodruff & L.D.Benson

A small cactus of limestone habitats on the Edwards Plateau in Texas. Observations after two winter burns allowed direct plant survival to be distinguished from subsequent growth rate, fruiting and the relationship between damage and grass distribution.

(Engelm.) N.P.Taylor

(L.D.Benson) N.P.Taylor