Figure 13 in REVIEW Going underwater: multiple origins and functional morphology of piercing-sucking feeding and tracheal system adaptations in water scavenger beetle larvae (Coleoptera: Hydrophiloidea)

Figure 13. Summary of the main structures related with metapneustic respiratory system. A, Tropisternus latus (Brullé, 1837), spiracular chamber, first-instar larva, light microscope photograph, dorsal view. B, Helochares ventricosus Bruch, 1915, spiracular chamber, first-instar larva, light microscope photograph, dorsal view. C, Tropisternus latus (Brullé, 1837), spiracular chamber, first-instar larva, light microscope photograph, dorsal view. D, Helochares ventricosus Bruch, 1915, abdominal spiracle, first-instar larva, light microscope photograph, dorsal view. E–H, Tropisternus setiger Germar, 1824, SEM micrograph: E, spiracular chamber, third-instar larva, ventral view; F, detail of the terminal spiracle with dust filter, third-instar larva, ventral view; G, abdominal spiracle, first-instar larva, dorsal view; H, detail of the closed abdominal spiracles, first-instar larva, dorsal view. I, J, Oocyclus iguazu (Oliva 1996) third-instar larva, SEM micrograph: I, spiracular chamber, dorsal view; J, biforous abdominal spiracle, dorsal view. K, Laccobius kunashiricus Shatrovskiy, 1984, spiracular chamber, third-instar larva, SEM micrograph, dorsal view.