Thelocactus

Halda & Panar.

Thelocactus bicolor

A variable cactus from the borderlands of southwestern Texas and northeastern Mexico. Its diagnostic characters include strong spines, ribs divided into tubercles and large, pink-purple flowers.

A species with a narrow estimated niche in the comparison of nine Thelocactus. Rainfall in both the wettest and driest quarters of the year was important for the occurrence records used.

A Mexican Thelocactus whose site distribution in the niche analysis was most strongly associated with precipitation in the driest quarter. The current treatment also includes names of formerly distinguished varieties.

A species with a strongly distinctive thermal profile in the comparison of Thelocactus niches. The model was built from 11 records, so assessment of the breadth of suitable conditions needs to account for the small sample.

A Mexican cactus with flattened stems and distinct tubercles, with white or pink flowers. A site discovered in Tepezalá in 2021 documented the species in Aguascalientes and extended its known range southwestwards.

Říha & Busek

A species encompassing plants with yellow and violet-carmine flowers. In the Querétaro population examined, described as subspecies schmollii, fruiting depended on cross-pollination, and the main visitors were pollen-collecting bees.

(Rebut ex Quehl) W.T.Marshall

A species accepted as distinct from Thelocactus rinconensis. In the niche comparison, it was distinguished by the importance of thermal conditions and the relatively greater importance of topography.

A Mexican Thelocactus species for which precipitation in the wettest quarter was most important in occurrence modelling. The association concerns the distribution of the sites used and regional climatic data.

A species also known under the historical name Hamatocactus setispinus. Pollen microscopy of material preserved in the ISL herbarium showed elongated, tricolpate grains with a granular, perforated exine surface.

A species described in 2018 from northern Oaxaca. It grows on limestone faces in narrow canyons and is distinguished by small reddish purple flowers, poorly differentiated spines and details of seed structure.

The species with the narrowest estimated niche in the modelled comparison of nine Thelocactus. Its occurrence distribution was associated primarily with the relationship between daily and annual temperature changes and precipitation in the wettest quarter.