Ferocactus mathssonii

Ferocactus mathssonii is a species of Ferocactus found in Mexico.

Description
Ferocactus mathssonii is a solitary cactus with attractive hooked central spines, occasionally branching from the base. Its flowers are a unique coppery color. The stems are flattened globular to egg-shaped, green to bluish-green with a grey glaucescence, up to 15 cm tall and 8 cm wide, with 9-13 prominent ribs and strongly tubercles, approximately 6-9 mm broad and 9-15 mm tall. Areoles are roundish, around 2-2.5 mm apart, 3-5 mm in diameter, with greyish-yellowish wool, and 1-4 curving, prominently hooked central spines that are 5-9 cm long and 1-1.5 mm wide, along with 3-8 radial spines. The spines are strong, tannish-white to greyish-pink or purple, slightly flattened, and do not obscure the stem. The plant produces several buds in spirals at the apex, with usually 3-5 or more flowers opening at a time. The flowers are cylindrical to funnel shaped, 2-4 cm long and 2-3 cm wide, with inner petals tannish to brick red, and outer tepals with brownish midribs. Filaments are yellow or maroon, up to 6 mm long, with yellow anthers. The style is 1.2 cm long, reddish, with stigma lobes 10-14, yellow or orange. The pericarpel has toothed scales up to 6 mm long. The plant blooms from March to May, with flowers opening in the morning and closing partially at night, reopening for 2-3 days. Fruits are 1.5-2.5 cm long, ovate to globose, fleshy, red, with black seeds that are 1.3-1.5 mm long.

Distribution
It grows in desert hills and flats, often on limestone-rich substrates, among desert shrubs or in open grassland, usually near grass clumps in Guanajuato to San Luis Potosí, Mexico.

Taxonomy
The plant was first published without a description by Karl Moritz Schumann as Echinocereus mathssonii in 1893.