They are not "regional morphs per se, but rather all three are natural color variations that are found in the wild that can, and are bred into all the known morphs in the hobby. The tricolor, tangerine and bicolors can be totally normal, or albino or hypo, etc...once any of those particular recessive genes has been introduced.
There are some that have certain separate types of these variants, and some that have all these types. Additionally these different co-dominant color traits are also bred together as well, and can have intermediate individuals, or ones that look more one color than the other. A great deal of this can also have to do with what previous parent and grandparent stock look like. You can also breed two like colored parents together and get different looks within a clutch as well. There is no real correct, or incorrect pairing of these color variants, but are more individual personal taste.
Bicolored animals are simply animals that have the tendency of the inner light triad(rings of three) band to become very close, or identical to the wider RBR(red body ring). On the same token, the albino forms with much whiter bands are individuals that would normally have no other "underlying" pigment(s), which is why other's can have a tendency of displaying a yellowish, peach, or even a greenish tint to their outer white rings.
~Doug





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"Better to be silent and thought a fool, than to open mouth and remove any doubt!"