Your frontosa's are the burundi-variant.
There are two major geographic groupings of frontosa (the northern types and southern types).
Each of these grouping are comprised of sub-groups (for example, the northern types are the burundi's and kigomas; the southern sub-groups (the Gibberosa's) are the zambian, tanzanian and zaire sub-groups). The kigoma's and boulomboro's are 7-stripe variants. All of the others have 6 stripes.
Within each of the above sub-group are the variants (for example, the mpimbwe-variant is within the tanzanian group, moba's are within the zaire group, etc).