Family Semelidae
I have several hundred colored Semeles with patterns in my collection which are usually listed under Purplish Semeles, Semele purpurascens (Gmelin, 1791). I will be listing the colored Semeles by the three main colors: purple, orange, and blonde(yellow/tan). My argument is that if you call a semele purple when it's obvuiously orange that it's not accurate. I understand that there is no other accepted scientific designation so I've kept that the same.
I also have a large number of white Semeles which are Atlantic White Semeles: Semele proficua, (Pulteney, 1799).
The Purplish Semele is a thin smooth oval shell about 1" to 1.5" with very fine concentric lines whose hinge points to the right slightly. It's identified by its purple color and detailed patterns around its edge. The color is purple and other colors with similar patterns are usually grouped under the Purplish title. The colors are usually orange, blonde (yellow/tan), and rarely transclucent or white.
The juvenile colored semeles (usually grouped under Semele purpurascens) may not have the eloborate concentric checkered patterns and may be primarily purple, orange or blonde. The hinge of these semeles is off-center which the hinge of the white semeles is centered which is an easy way to tell them apart.