Select the vertebrate.

 - saturn butterfly
 - metallic tarantula
 - sunfish
 - weaver ant
A saturn butterfly is an insect. Like other insects, a saturn butterfly is an invertebrate. It does not have a backbone. It has an exoskeleton.
A weaver ant is an insect. Like other insects, a weaver ant is an invertebrate. It does not have a backbone. It has an exoskeleton.
A sunfish is a fish. Like other fish, a sunfish is a vertebrate. It has a backbone.
Like other tarantulas, a metallic tarantula is an invertebrate. It does not have a backbone. It has an exoskeleton.