Acodus

Acodus is an extinct genus of conodonts, primitive chordates resembling eels. They are known primarily from their tooth-like microfossils, the conodont elements, which are used as index fossils in biostratigraphy. Acodus elements are typically simple cone-shaped structures, often with a basal cavity. The genus is important in understanding the evolution of conodonts, as it represents one of the earliest and most basic forms of these organisms.

Acodus is found in rocks of the Ordovician period, with occurrences documented globally. The precise taxonomy and phylogenetic relationships within the genus have been subject to debate and revision, reflecting the challenges inherent in studying extinct organisms known solely from their skeletal elements. Variations in element morphology are used to differentiate species within the genus. The study of Acodus contributes to our understanding of early vertebrate evolution and the paleogeography of the Ordovician period.