Etymology -Named after the Spaniard Manuel Fraile who looked after the cacti collection of the US Department of Agriculture at the time Britton and Rose were preparing their book.Frailea species are all small solitary or clustering plants with flattened globose stems that rarely exceed 2 inches (5cm) in diameter. The stems have few to many very shallow ribs which may be straight or wavy. Spines are quite small and weak if present at all and pose little threat to the finger tips. The yellow flowers are often larger than the stems and open in the heat of the day for a short time, if at all. Frailea species are cleistogamous, meaning that often times the flowers do not even emerge, but rather they self-pollinate while still inside the plant. Many growers new to the genus are often surprised to find a fruit spilling seed all over on a plant that they never noticed in flower. The fresh seed germinates quite easily and because of the surprise fruit that shows up, seeds are already growing at the base of the main plant before the owner knows the seed is there.
While several species are popular in cultivation, the status of this genus is the wild is uncertain. Developmental pressures and grazing threaten many species which may have very limited ranges. The species inhabit much of the central portions of South America, but a good understanding of the species is definitely lacking.