Gymnocalycium amerhauseri is a small single headed, flattened cactus, with peculiar dark green bodies with short adpressed spines in spider-like clusters.

Flowers: The flowers are near the apex, funnel-shaped, creamy white to pale pink up to 3 centimetres at anthesis. Throat reddish. Scales green, bordered pinkish-white. Blooming appears recurrently from June to autumn. It flowers quite readily as a young seedling.

Stem: Flattened spherical to spherical, plump, glossy dark green, bluish green or greyish-green, up to 2,5 cm tall, 5-6 cm in diameter.

Summer growing species. Relatively rapidly growing and easily flowering species. This plant needs plenty of space for its roots, repotting should be done every other year or when the it has outgrown its pot. Needs moderate to copious waterings in summer, but do not overwater. keep dry in winter at a minimum temperature of 0°C. Reputedly resistant to frost if kept on the dry side prior to, and during, cold weather (hardy to -12 C ° C, or less for short periods), but for safe cultivation it is best to avoid freezing temperatures. The plant tolerates extremely bright situations but enjoys filtered sunlight or afternoon shade, inside it needs bright light, and some direct sun. Tends to bronze in strong light, which encourages flowering and heavy spine production, but is likely to suffer from sun scorch or stunted growth if over exposed to direct sunlight during the hottest part of the day in summer.
Propagation: Seeds germinate in 7-14 days at 21-27° C in spring

Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz