Df(3L)BSC884 was isolated as a FLP recombinase-induced recombination event involving P{XP}Eaf6d06605 and PBac{RB}CG32418e03237. The deletion was isolated as a chromosome lacking miniwhite markers in progeny of w1118; P{hs-hid}3, Dr1/TM6C, Sb1 cu1 females crossed to P{hsFLP}1, y1 w1118; P{XP}Eaf6d06605/PBac{RB}CG32418e03237 males. The males were heat shocked as larvae as described in Parks et al. Nature Genetics 36: 288-292, 2004 (FBrf0175003). This cross and crosses in preceding and succeeding generations maintained the original genetic background of the Exelixis insertion stocks (Thibault et al., Nature Genetics 36: 283-287, 2004; FBrf0175002). The recombination event generated the genetic element P+PBac{XP5.RB3}BSC884 from the segment of P{XP}Eaf6d06605 to the left of its FRT site and the segment of PBac{RB}CG32418e03237 to the right of its FRT site. Its presence was verified using the PCR methods and primers described in Parks et al, with the substitution of the primer 5'-GCTTCTAAACGCTTACGCATAAACGATG-3' for the RB3' plus or RB3' minus primer in the Hybrid PCR protocol in the Supplementary Methods. The breakpoints of Df(3L)BSC884 predicted from the Release 5 genomic coordinates of the transposable element insertion sites are  3L:5601375 ;5770185 and the cytological breakpoints predicted from these coordinates are 64D6;64E7. Df(3L)BSC884 failed to complement scny02331.