What's eating my perplexing rebutia?

Perplexing Rebutia (Rebutia perplexa) is a small, clustering Bolivian cactus grown as a houseplant. Like all Rebutia, it is most troubled by root mealybugs spreading through clusters and standard mealybugs between offsets. Spider mites can appear in warm, dry rooms. Minimal watering and annual inspection at repotting time are the key defenses.

Wilting or shriveling despite correct watering; white waxy residue on roots and at the base of the plant. Remove plant from pot, wash all soil from roots, treat with neem drench or imidacloprid, dry, and repot in fresh well-draining mix.

White woolly tufts between the dense clustering stems; slow growth; sticky honeydew. Dab with isopropyl alcohol; apply neem oil or insecticidal soap spray across the entire cluster; repeat every 7–10 days.

Tiny reddish mites and fine webbing between spines; stippling or bronzing on stem surface in dry conditions. Rinse with a gentle water spray; apply neem oil or miticide; increase humidity slightly and improve air circulation.