Final answer:
The fossilized fish with jaws but no true bones belongs in the early gnathostome category in the evolutionary history of vertebrates, positioned on the cladogram after the split from jawless fishes and before the appearance of bony skeletons like those of the Osteichthyes.
Step-by-step explanation:
The fossilized fish in question has jaws but no true bones. This places it among the early gnathostomes, which are jawed fishes in the evolutionary history of vertebrates. Since it lacks true bones, it does not belong to the Osteichthyes (bony fishes) clade, which includes both the Actinopterygii (ray-finned fishes) and Sarcopterygii (lobe-finned fishes) sub-groups, as these possess an osseous skeleton.
The presence of jaws in the fossil indicates that it is more derived than the jawless fishes, such as the Agnatha, which includes the more primitive Myxini (hagfish) and Petromyzontida (lampreys). Since it lacks true bones, it may be closer to the cartilaginous Chondrichthyes clade, which includes living examples like sharks and rays.
Gnathostomes evolved from jawless fishes by developing jaws and paired fins, allowing them to become active predators. This transition from jawless to jawed fishes is a significant evolutionary event, leading to the diversity we see in modern fishes and all later vertebrate lineages.
Therefore, the fossilized fish would fit on the cladogram right after the split between jawless fishes and the gnathostomes, but before the development of the bony skeleton characteristic of the Osteichthyes.