Figs 79–84. SEM of proboscis and hooks of Pachysentis canicola (Oligacanthorhynchidae) (figs 79–82) and Corynosoma strumosum (Polymorphidae) (figs 83, 84): 79 — the proboscis of a female P. canicola showing hook arrangement and sensory pores at posterior proboscis and neck; 80 — an anterior hook deeply recessed in thick cuticular fold; 81 — a posterior hook also deeply recessed in a boat-like cuticular fold; 82 — a Gallium-cut cross section of a hook near its base showing the ventral protrusion as seen in other oligacanthorhynchid genera: Macracanthorhynchus and Nephridiacanthus; 83 — the proboscis of a specimen of C. strumosum showing its bare apical end and larger hooks at the bulge; 84 — a high magnification of a hook showing micropores.