Genus Lycaena Copper Butterfly Wing Posters
Members of the beautiful genus, Lycaena, belong to the group of butterflies known as Coppers. Although many of them are generally copper-like in color, some species exhibit convergent evolution towards the related Blue Lycaenid butterflies. This genus exhibits seasonal polyphenism where short day (Spring) forms have different patternation from their long-day Summer forms.
Another interesting observation about wing patterns is referred to as Oudemans’ principle. As you study the ventral wing pattern of a resting butterfly, you’ll notice the pattern often smoothly translates from the hindwing to the visible tip portion of the forewing. In contrast, the covered portion of the forewing lacks the patternation and is often more brightly colored making for a disorienting flash of color as the butterfly launches into flight. Oudemans’ principle can also be observed on the forewing patterns where design element align between the fore and hind wings when the butterfly is displaying its dorsal surfaces.
A fair volume of research has been conducted into the analysis of pattern element along with exploration into the developmental mechanisms of pattern formation. A good portion of this article was inspired by H. Frederik Nijhout’s book, “The Development and Evolution of Butterfly Wing Patterns.” Studying the commonality between the bewildering diversity of patternation found on the wings of butterflies and moths resulted in a generalize model of pattern elements and symmetries known as the Nymphalid ground plan. Although no single butterfly species exactly manifests all the pattern elements established in this model, it forms a useful reference framework to discuss the specific elements of any particular design. This model was initiated back in the 1920’s by B.N. Schwanwitsch and F. Seffert. The model identifies regional bands of symmetry that radiate out into the wing plane from the root where the wing attaches to the thorax. Reviewing the pattern elements of the model from the root out to the wing tips we find a wing root band, a basal symmetry system, a central symmetry system, a discal spot, border ocelli complex, parafocal elements and marginal bands. The model is enhanced with the recognition of venous strips as a major pattern element. (continued…)