Click To Enlarge. Juvenile Caimans are yellow in color with black spots and bands on the body and tail. As they mature, they lose this yellow color and the markings become less distinct. Adults are dull olive-green. Spectacled caimans are the most common species of the crocodilian family.The Spectacled Caiman is one of the smallest crocodilians, but is the largest of the caiman family.s they mature, they lose this yellow color and the markings become less distinct. Adults are dull olive-green. Spectacled caimans are the most common species of the crocodilian family. The Spectacled Caiman is one of the smallest crocodilians, but is the largest of the caiman family.