Anatomy is the best answer
The physical appearance of a trait is called the phenotype of an organism.
The term used to describe a harmless organism resembling a harmful one is batesian mimicry. Cryptic coloration or camouflage makes prey difficult to spot, while aposematic coloration is a type of coloration exhibited by animals with effective chemical defenses. Mullerian mimicry is a type of mimicry in which two or more unedible species resemble each other.
