<p>Developmental diversification of neuropil glia.</p>

Ncad (yellow) is used to visualize the neuropil and Repo (magenta) to label all glia. White dashed boxes delineate the area magnified in the panels below. <i>10C12</i>-Gal4 is expressed specifically in epithelial and marginal glia, as well as in Lamina wide field neurons. <i>54H11</i>-Gal4 labels epithelial and marginal glia and medulla neuropil glia. <i>Hand-T2A</i>-Gal4 expression is only observed in some medulla neuropil glia (filled arrowheads), and absent in others (empty arrowheads). <b>(F–H)</b> FLEXAMP memory cassette is used to immortalize L3 expression of the Gal4 lines in C–E and to observe the morphology of adult glia.

Only UAS-myrGFP expression is shown, and the neuropil shape is delineated in yellow dashed lines. Lamina and close-ups of medulla neuropil are indicated. Note that epithelial and marginal glia, that are indistinguishable at L3, diverge into specific morphologies and localizations in the adult <b>(F and G)</b>.

Tracings of L3 medulla neuropil glia show that they give rise to all morphotypes (ensheathing and astrocyte-like) and localizations (proximal, lateral and distal) of adult medulla neuropil glia <b>(G and H)</b>. xgo = outer chiasm glia, mng = medulla neuropil glia, lng = lamina neuropil glia, eg = epithelial glia, mg = marginal glia. Gal4-UAS (<i>>></i>). Scale bar = 20 µm.

The code used to generate the graphs can be found at <a href="zenodo.org/records/21890456" target="_blank">zenodo.org/records/21890456</a>.</p>