The Mimic Ladybug Spider, found in eastern Asia, disguises itself as a ladybug (or ladybird). 

While we generally consider ladybirds (not technically bugs) harmless, there’s a reason why they can safely be such bright colors. Through a mechanism known as “reflex bleeding,” they release a noxious alkaloid mixture that gives its predators a very bad taste. 

Batesian mimicry is the term for when animals copy a design or color scheme of another, more inedible animal in order to avoid being eaten. Considering most ladybirds aren’t predatory like the spider, it could very well serve a double purpose.