Tullimonstrum gregarium: A Probable New Member of the Early Jawless Vertebrates

This research proposes a new morphological and taxonomic interpretation of the fossil organism Tullimonstrum gregarium, commonly known as the “Tully Monster.” Based on comparative anatomy and fossil analysis, this study argues in favor of a basal vertebrate identity, closely related to agnathan lineages such as conodonts and modern lampreys. The paper discusses the anatomical features, environmental context of Mazon Creek, and why previous molluscan classifications may be incorrect. This reinterpretation seeks to contribute to the ongoing debate over the phylogenetic position of this enigmatic species.