Select the vertebrate.

 - curlyhair tarantula
 - emerald tree boa
 - red-spotted purple butterfly
 - bess beetle
An emerald tree boa is a reptile. Like other reptiles, an emerald tree boa is a vertebrate. It has a backbone.
A bess beetle is an insect. Like other insects, a bess beetle is an invertebrate. It does not have a backbone. It has an exoskeleton.
A red-spotted purple butterfly is an insect. Like other insects, a red-spotted purple butterfly is an invertebrate. It does not have a backbone. It has an exoskeleton.
Like other tarantulas, a curlyhair tarantula is an invertebrate. It does not have a backbone. It has an exoskeleton.