Glial cells play structural and functional roles central to the formation, activity and integrity of neurons throughout the nervous system. Here, using the genetic model Drosophila melanogaster, reseearchers identify a new glial cell type in one of the most active tissues in the nervous system—the retina. These cells, called ommatidial cone cells (or Semper cells), were previously recognized for their role in lens formation. Using cell-specific molecular genetic approaches, this study demonstrates that cone cells (CCs) also share molecular, functional, and genetic features with both vertebrate and invertebrate glia to prevent light-induced retinal degeneration and provide structural and physiological support for photoreceptors.