Fig. 4. Oncopeltus even-skipped RNAi phenotype. (A1-A3) Uninjected hatching-staged animals. (A1) Lateral view. Thoracic and abdominal regions are marked. (A2) Dorsal aspect. (A3) Ventral view. (B1-B3) Class III (weak) phenotype. (B1) Lateral view of class III animal. Thorax weakly affected, all legs are present. The abdominal region is shortened. (B2) Dorsal view. Abdominal segments marked by arrowheads. (B3) Ventral view. (C) Fully formed germband of uninjected embryo, stained for engrailed. (D1,D2) Putative class III germband stained for engrailed. (D1) Lateral view. Head and thorax are at most weakly affected, but abdominal region is shortened and shows strong segmental defects. As the germbands were extremely curved and ruffled, and therefore impossible to mount under a cover slip, they were photographed unmounted. (D2) Dorsal aspect, showing segmentation defects in abdomen. (E1,E2) Class II (moderate) hatching stage embryo. (E1) Lateral view showing presence of first thoracic leg. Second thoracic leg is also present but difficult to see in this photograph. Third thoracic leg is missing. Abdomen is now severely shortened. (E2) Dorsal aspect. There are segmental defects in head and thorax. (F) Putative class II germband stained for engrailed. Body now highly reduced, and second and third thoracic legs are missing. Gnathal and first thoracic appendages still present. (G) Class I (strong) embryo. Only anterior structures such as labrum, eye and antenna are formed. (H1-H2) Class I embryo stained for engrailed (H1) and DNA (H2). All segments posterior of the head are missing. ANT, antenna; MN, mandible; MX, maxillary; LB, labium; T1-T3, thoracic segments; A, abdomen. Scale bars: 200 µm in A1-G; 100 µm in H1 and H2.