ostracoderm (noun)

1. In the documentary 'Ancient Sea Creatures', scientists discuss the fascinating evolution of the ostracoderms.

2. The protagonist in the graphic novel series 'Prehistoric Chronicles' is an ostracoderm warrior on a quest to save his homeland.

3. The sculpture titled 'Armored Guardian' depicts a detailed representation of an extinct ostracoderm.

4. The museum's atrium features a stunning mural depicting a prehistoric ocean scene with various ostracoderms swimming amidst the coral reefs.