Programmed DNA elimination removes specific chromosomes during development, but the sequences involved remain unclear. A new study from the lab identifies novel satellite DNAs in Bradysia coprophila and maps their chromosomal distribution, revealing that L chromosomes lack the centromeric repeat found on X and autosomes. The work also provides cytological confirmation of two distinct L chromosomes, refining our view of this enigmatic system. These findings lay the groundwork for uncovering how satellite DNA may guide chromosome-specific elimination.