Fig. 2. Electron micrographs of the dorsal white tegument of the opisthosoma (boxed in Fig. 1A). (A) Epidermal cells with type I granules (arrow). Electron-lucent areas (holes) are present because granules are sometimes broken up by the microtome cutting. Bar, 2 µm. (B) Detail of type I granules (bar, 0.5 µm). The inset shows a detail of the abundant glycogen rosettes in the epidermal cell cytoplasm (arrow) (bar, 0.5 µm). (C) Detail of the structure of rough endoplasmic reticulum (RER) organized into several concentric rings. Note the presence of large number of mitochondria (arrows) related to these structures. Bar, 0.5 µm. (D) Another detail showing the RER structure in close association with granules (arrow). N, nucleus. Bar, 0.5 µm.