Loganellia

Loganellia
Loganellia scotica (Fossil and model, Museum am Lowentor, Stuttgart)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Thelodonti
Order:	Loganelliformes
Family:	Loganellidae
Genus:	Loganellia Fredholm, 1990
Type species
Loganellia scotica (Traquair, 1898)

Loganellia is a genus of jawless fish which lived between 430 - 370 million years ago, during the Silurian and Devonian epochs of the Paleozoic.^[1] Loganellia belonged to the Thelodonti class and like other Thelodonts possessed scales instead of plate armor.

Loganellia are thought to be more closely related to the crown group of gnathostomes than conodonts. They are noted for their denticle whorls - oropharyngeal denticles that lined their branchial bars - which are thought to be homologous with other, later gnathostome teeth. In this sense, Loganellia may possess the earliest known dental structures related to modern teeth, and would have evolved in the throat, rather than through dermal denticles or jaws.^[1]

Fossil

Loganellia, swimming in a shallow sea 400 million years ago.

References