Bugs and beetles are both insects. Bugs have a mouth part that’s like a needle — the bug pierces the food (usually a plant or another insect) and sucks the liquid out. Beetles have chewing mouthparts. They chew their food.

As they are insects, beetles and bugs both have six legs. Spiders have eight legs. Spiders are not insects; they have their own class (arachnids).

The bug in the photograph is an assassin bug. You can see its needle-like mouth part (rostrum) under its head. This is a young one — its wings are not fully formed. Assassin bugs stab their prey (usually spiders and other insects) with the rostrum, which is hollow, and then inject saliva into the prey. Their saliva turns everything inside the prey to liquid which the assassin bug sucks up through the rostrum.

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