The correct way to record the name of a complex is using only a simple scientific name (without hyphens).

Some examples:

Complex Hyla versicolor: Gray Tree Frog Complex, for Hyla versicolor/Hyla chrysoscelis
Complex Pantherophis alleghaniensis: Eastern/Gray Ratsnake Complex, for Pantherophis alleghaniensis/Pantherophis spiloides
Complex Laphria canis: for Laphria canis, L. franciscana, L. sicula, L. winnemana