Fig. 3: Confocal series of normal wing scale development in H. sara.

Cell nuclei counterstained with DAPI (blue). A–C Early wing scale development showing cytoplasmic projections from the wing epithelium at 25%. A Phalloidin staining (green) of actin in the nascent scales. B, C Anti-alpha Tubulin immunostaining (red) reveals differing amounts of cytoplasm in developing cover (arrowhead) and ground (arrow) scales and outlines of the socket cells. D–F At 37.5–44% the scale cell is a sac filled with organised actin bundles (green) (D) and surrounded by a cellular membrane, highlighted by WGA staining (red) (E). Forming sockets are clearly visible (F) with the actin bundles passing directly through them. At 50–56% (G–I) the scales resemble adult scales (Fig. 1D). The distal forewing (G) shows hundreds of developing scales. H overlapping wing scales adjacent to a wing vein with actin-rich hairs protruding from the vein (arrowhead). I The actin (green) within the scales is highly organized at 50% and extends to the proximal portion of the scale fingers. J–L final stages of scale development. J gaps between the phalloidin stained actin bundles (green) highlights actin sub-bundling (K) WGA (magenta) now stains the chitin being deposited extracellularly (L) Merge of actin (green) and WGA (magenta) shows the chitin being deposited between the actin bundles (Li). Scale bar lengths: (A, B, E, I) 20 μm; (C, D, F, J, K, L) 10 μm; (G) 300 μm; (H) 50 μm; Li 2 µm.