It is named after American philanthropist Gertrude Webster, who cofounded the Desert Botanical Garden in Phoenix, Arizona.

Golden yellow, brown, or white spines grow about 1 cm (0.39 in) long from closely spaced areoles.

[3] It is likely native to San Pedro Nolasco Island in the Gulf of California, though it may have some distribution in mainland Baja.

It occurs on other islands in the Gulf of California, including Isla San Lorenzo Sur and Isla Las Ánimas growing on rocky slopes at elevations of up to 350 m.[3] The plant is found growing along Agave chrysoglossa, Mammillaria multidigitata, and Opuntia bravoana.

In cultivation, it should be watered regularly between March and October, and given a deep pot to ensure adequate drainage.