Nepenthes truncata Spots: Light Color vs. Fungus vs. Pest Damage

A grower posted photos of reddish spots on N. truncata, unsure if fungus, bugs, or light response.

An expert (Jake) explained: reddish/orange/purple spots in bright light are normal pigmentation. Fungus often grows on dried nectar—rub with a white paper towel; if color transfers, it’s mold (harmless, treat with neem or sulfur). If spots don’t rub off and are reddish, it’s light color. Brown, dying patches suggest pests or other issues.