Line drawings of specimens of Cavisoma magnum collected from Mugil cephalus in the Arabian Gulf.

• 1. A male specimen. Note the thick body wall here and elsewhere.
• 2. The posterior part of the same male in Figure 1 showing the reproductive system.
• 3. A ripe egg removed from the body cavity.
• 4. The proboscis of an adult male.
• 5. The anterior part of the trunk of a male specimen showing the relationship in size and shape of the proboscis, receptacle and lemnisci.
• 6. Posterior part of the trunk of a female specimen showing the reproductive system. Note the simplified vagina, long uterus, and the two para-vaginal bundles of fanning fibers.
• 7. One row of proboscis hooks showing three types of hooks/roots, the anterior-most hook with lateral hook with prominent manubrium, the regular subapical hooks with posteriorly directed roots, and the posterior hooks with root stubs and anterior manubria. The hooks and inter-hook spacing are identical to those in actual specimens.