Digitalis thapsi, which has been called mullein foxglove in the US, is a flowering plant in the genus Digitalis that is endemic to the Iberian Peninsula, where it occurs in eastern Portugal and central and western Spain. It is of commercial importance as an ornamental plant. Hybrids with D. purpurea have proved successful and are fertile. Names A Missouri Botanical Garden website calls it mullein foxglove. Local vernacular names recorded for this species are abeloura, abeloura-amarelada, aboleira, aveloeira, dedaleira, luvas de Santa María, pegajo and rabo de raposa in Portuguese, whereas in Spanish the most common name is dedalera, followed by viloria, viluria, giloria, dedales and mataperla, but it has also been called abiloria, abiluria, abortones, bacera, beleño, biloria, biluria, campanilla, cascante, cascaor, chupadera, chupamieles, chupera, cohete, cohetera, cohetes, deales, dedales de niño, dedales purpúreos, dediles, digital, digitalis, emborrachacabras, estallones, goldaperra, guadalperra, gualdaperra, guardaperros, hueltaperra, mata de lagartija, mataperros, rabera, ravera, raéra, restalladera, restralleti, restrallos, sabia, tuercecuellos and vueltaperra. Taxonomy It was first described in the modern taxonomic system by Carl Linnaeus in 1763. The genus Digitalis was formerly assigned to the family Scrophulariaceae, but it is now considered to belong within the Plantaginaceae. Hybrids Joseph Gottlieb Kölreuter, a German botanist, observed that D. thapsi had many characteristics of D. purpurea after four to five generations of cultivation, and that the former became indistinguishable from the latter, a report that was considered "probably" trustworthy by Charles Darwin. D. thapsi and D. purpurea hybrids are generally fertile. In many areas of Spain and Portugal populations of D. thapsi and D. purpurea meet, and introgression is common. These have been known as D. purpurea nothosubsp. carpetana and D. minor in error in two older Portuguese works (1906, 1913), but this hybrid is now generally known as D. × coutinhoi. Description Habitus Digitalis thapsi is a perennial plant. Its yellow-green leaves are ovate to oblong in shape and decurrent, with winged bases. The flowers, stems and leaves are covered with a dense indumentum of tiny hairs, giving them a soft appearance. These yellow-green hairs (trichomes) are exclusively glandular. The entire plant is very sticky (glutinose). It is caespitose, meaning it grows with its large leaves tightly arranged into one, or a number, of rosettes growing at or just above ground level. In older plants the base becomes woody and highly branched at ground level, so that a single plant has multiple rosettes. The