Same genus should not be housed together. So no neocardia species (snowball shrimp, blue pearl, red cherry - including sakura, fire red, taiwan red, or yellow) and no Cardinia species (tiger shrimp, cristal red shrimp, bee shrimp, crystal black shrimp, blue bolt, red wine, BKK, etc).
You CAN house neocardia species with cardinia species without an issue as long as your parameters meet the needs of both shrimp types. Usually neocardia are more hardy than cardinia.