A new coelacanth from the Middle Devonian of Latvia

We describe a new species of coelacanth, Miguashaia grossi sp, nov., recogn ized from isolated cranial, shoulder girdle bones and scales from the Upper Givetian Gauja and Lode Formations of two Latvian localities. This coelaca nth, together with comparisons with other Devonian coelacanths, allows a mo re precise description of the plesiomorphic condition of the lower jaw, sho ulder girdle, and palate. These plesiomorphic conditions are as follows. Th e dentary is shallow throughout, the articular-retroarticular is deep poste riorly where it is developed as two processes-one for the symplectic articu lation and the other demarcating the posteroventral angle of the jaw. In th e shoulder girdle plesiomorphic attributes include the large triangular cla vicle, a cleithrum which is directed anterodorsally and possibly a large an d polygonal extracleithrum. In the palate the pterygoid shows a dorsal proc ess of unknown function mid-way along the dorsal margin and this is also a plesiomorphic feature of coelacanths.