The left half of a tetrapod lower jaw, from the Parrsboro Formation (Pennsylvanian, Westphalian A) of Nova Scotia, is preserved as a natural mold in a sandstone. Most of the features of this lower mandible are primitive for tetrapods or non-ichthyostegalian tetrapods. Although the presence of an adsymphysial tooth plate in this specimen is regarded as the retention of an osteolepiform feature, the tusk and replacement pit on this dermal bone may be unique to this taxon. The poor preservation of the lower jaws associated with some previously described Paleozoic tetrapods, together with the unique features in other early tetrapod jaws, precludes the reference of this mandible to any known tetrapod taxon.

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