Mammillaria camtotricha marnier
(This plant comes in a 3.5" pot. You will receive a very similar plant to the one in the picture. It may or may not be blooming at the time of your purchase. The plant is shipped in its pot to prevent any damage to the roots).
This cactus is commonly known as the Bird's Nest cactus, it's a small cactus with large clumps of fleshy stems clustering from the lower part. Its body is very green, with curly orange and yellow thorn that curve back into the body. It produces adorable small white flowers.
Frost tolerance: Hardy to 28°F (-2°C)
Minimum avg. temperature: 50°F (10°C)
Sun exposure: Light shade in summer
Origin: Mexico (Queretaro)
Growth Habits: Clumping, up to 2" tall (5 cm), 3" wide (7.5 cm)
Watering Needs: Moderate water. Keep dry in winter.
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz