develops from expresses slbo follicle cell border follicle cell CL:0000579 fly_anatomy.ontology A follicle cell that migrates from the anterior pole of the egg chamber, between the nurse cells, to the anterior of the oocyte where they participate in formation of the micropyle. About 6-10 border cells per egg chamber migrate as a tightly associated cluster. border cell Can be identified based on expression of slbo (Rust et al., 2020). FBbt:00004905 anterior terminal follicle cell