What's eating my owl eyes cactus?

Owl Eyes Cactus (Mammillaria parkinsonii) is a clustering houseplant vulnerable to mealybugs hiding between the twin-spined tubercles and at the crown of each head. Root mealybugs are a secondary risk in poorly draining mix. Scale and spider mites also occur in dry indoor environments. Inspect all heads in a cluster, not just the outermost.

White fluffy wax between tubercles and in crown area, yellowing, reduced vigor Alcohol swabs on each affected spot; separate infested clustering offsets to prevent spread; neem oil spray as preventive measure

Mysterious wilting and slow growth, white powdery coating visible on roots when unpotted Bare-root the plant, clean all roots, soak in diluted systemic insecticide solution, allow to dry fully before repotting

Hard shell-like bumps on the cactus body, particularly at the base, honeydew and sooty mold Physical removal with toothbrush and alcohol swab; horticultural oil spray as follow-up treatment