Summary:
- The article discusses the discovery of a new species of ancient, giant, armored fish, *Janusiscus schultzei*, which provides critical insights into the early evolutionary history of jawed vertebrates (gnathostomes).
- It highlights how the fossil, found in Siberia, displays a mosaic of anatomical features that bridge the gap between two major groups of early fish—the placoderms and the osteichthyans—offering a clearer understanding of the "evolutionary toolkit" that led to modern vertebrate anatomy.