[3] The majority of Cochleosaurus remains have been discovered in fossil assemblages in the Late Carboniferous Sydney Coalfield in Nova Scotia and the Kladno Formation in the Czech Republic.

[1][2] The first Cochleosaurus specimen to be discovered was excavated by Antonín Jan Frič in the Westphalian D fossil deposits in Nýřany, Czech Republic, in1879.

He named this species C. florensis in honor Florence, Cape Breton, Nova Scotia, the town nearest the site where the specimens were discovered.

[2] However, further analysis has discovered that both C. bohemicus and C. florensis, like other cochleosaurids, had lateral lines, but with the sensory canals enclosed in bone, making them invisible from the outside.

[5] Muscle attachments for the retractor bulb are thought to have been on the ventral surface of the circumorbital bones, where there is a depression on both sides of the skull, anterolateral relative to the denticle field.

Cochleosaurus bohemicus had sharp crests on the ventral surface of both the left and right prefrontal circumorbital bones, parallel to the anteromedial margin of the orbit.

[7] Analysis of specimen synapomorphies in adult and juvenile C. bohemicus by Sequiera (2003) places Cochleosaurus as a sister taxa to Chenoprosopus.

Analysis of sediment from the Sydney Coal Field, where the C. florensis specimen was first discovered, found that the habitat had little to no fresh water and that the level of inundation was highly variable.

The fossil assemblage in the Klando Formation shows that this was a diverse freshwater habitat which supported a large number of fish species and aquatic plants.

Like the salt marshes inhabited by C. Florensis, the sediment deposits from this region show that the lake was subject to dramatic changes in water level, partly influenced by seasonal cycles  characteristic of Pangea during the Muscovian period.