Genus: Paleothyris CARROLL, 1969
Etymology: Greek, palaios, “ancient”, Greek, thyris, “opening, passage, hole”: Ancient (skull) opening.

Species: acadiana CARROLL, 1969
Etymology:

Holotype: MCZ 3481

Locality: Dominion Coal Company, strip mine No. 7, 2 miles north of Florence, Cape Breton County, Nova Scotia Province, Canada.

Horizon: Morien Group.

Biostratigraphy:

Age: Middle Pennsylvanian.

Material: Fragmentary skull and fragmentary skeleton.

Referred material:

MCZ 3482: Most of skeleton with skull somewhat disarticulated.

MCZ 3483: Isolated skull roof.

MCZ 3484: Posterior portion of skull roof, palate, and jaws, cervical vertebrae and dermal shoulder girdle.

MCZ 3485: Disarticulated elements of skull and postcranial skeleton.

MCZ 3486-3492, 3472-3477: Disarticulated portions of various individuals.