Astrophytum

Astrophytum is a genus of four species of cacti. These species are sometimes referred to as living rocks, though the term is also used for other genera, particularly Lithops (Aizoaceae)

1 Astrophytum asterias
2 Astrophytum capricorne
3 Astrophytum myriostigma
4 Astrophytum ornatum

I will start with Astrophytum asterias and Astrophytum capricorne.

• Astrophytum asterias is an attractive, spineless cactus also known as a Sand Dollar Cactus, a Sea Urchin Cactus, and also as Star Peyote. They are typically small, often 2-6 inches in diameter and usually 1-2 inches tall. In the wild, they flower throughout most of the summer season.

As with certain other slowly maturing cactus, the Astrophytum asterias has been listed as endangered, and its decline in the wild has been largely attributed to over-collection and poaching. Other contributing factors are thought to be urban development and herbicides. Fortunately, the cactus is readily propagated by seed, and its rarity in the wild ensures that most such plants encountered in nurseries are seed grown. The popularity of this species among collectors and enthusiasts has ensured that a number of cultivars are available. One such cultivar is the "Super Kabuto", a highly spotted white clone.

• Astrophytum capricorne known as the Goat's horn cactus has more spines than most Astrophytum species. Astrophytum capricorne and its varieties are very variable in their habit even in small areas. Plants vary in the amount of flock on the surface, in the number, length, shape and colur of the twisted spines and in the size of the stems.