Eggs of Parapsalis infernalis (Pygidicranidae) in two developmental stages of the pre-katatrepsis period, DAPI staining, UV-excitation, fluorescence microscopy. Lateral view, anterior to the top, ventral to the left. A Egg in late Stage 3. B Egg in Stage 5. – Abbreviations: Em – embryo; HL – head lobe; Pce – protocephalon; Pco – protocorm; Se – serosa. – Symbols: black arrowhead – anterior end of embryo; white arrowhead – posterior end of embryo. – Scale bar: 500 μm.