What's eating my star cactus?

Star Cactus (Astrophytum asterias) is a spineless, flat-bodied houseplant particularly vulnerable to mealybugs and root rot from overwatering. Its lack of spines makes mealybug inspection easier but also allows scale insects to attach more readily. Root mealybugs are a serious risk given its slow growth and sensitivity.

White waxy fluff at the areoles (white-dotted spots) and around the crown; plant body turns pale and soft Swab each areole with 70% isopropyl alcohol; spray the entire body with dilute neem oil; repeat weekly

Slow-growing plant suddenly collapses or turns yellow; white waxy coating found on roots at repotting Remove from pot, dip bare roots in a dilute neem or insecticide solution, let dry fully, and repot in fresh gritty mix

Flat tan discs along the ribs; the spineless body makes attachment straightforward for crawlers Remove with a cotton swab; apply horticultural oil to the whole plant; inspect again after 14 days