What's eating my tasmanian holly fern?

Tasmanian Holly Fern (Polystichum proliferum) kept as a houseplant is most bothered by scale insects on its glossy, leathery fronds, and by mealybugs in the crown. Spider mites can attack under dry conditions. Fungus gnats are common in overwatered soil. The tough, waxy fronds give some physical resistance, but inspect along midribs regularly as scale hides effectively there.

Hard brown or tan bumps clustered on midribs and petioles; honeydew and sooty mold; frond yellowing Scrape off with soft brush; apply neem oil or alcohol swab; follow up weekly for 4–6 weeks to catch crawlers

White cottony deposits in crown and along lower frond bases; reduced growth; sticky leaf surfaces Remove with isopropyl alcohol on cotton; spray with insecticidal soap; isolate and re-treat every 5–7 days

Fine webbing and pale stippling on frond surfaces; fronds dull and bronzed in very dry indoor air Increase humidity; rinse fronds; apply insecticidal soap or neem oil weekly for 3 treatments