Fig. 4 in A unique dentary suggests a third genus of batrachosauroidid salamander existed during the latest Cretaceous in the western USA

Fig. 4. Examples of pathological salamander mandibles. A.?Opisthotriton kayi Auffenberg, 1961, anterior portion of left dentary, OMNH 67080, from the Upper Cretaceous (upper Campanian) Kaiparowits Formation, OMNH locality V9, Utah, USA, in dorsal (A1), lingual and slightly dorsal (A2), labial A3), ventral (A4), and anterior-labial and slightly ventral (A5) views. Note symphysial end distorted by a bony swelling or callus (indicated by single asterisk), presumably formed by healing after an unknown injury. B. Ambystoma mexicanum (Shaw and Nodder, 1798), entire tooth-bearing ramus of left and right dentaries and anterior portion of areas for attachment of post-dentary bones, both from TMP 2010.30.09, an extant and captive bred individual: normal left dentary in lingual view (B1), pathological right dentary + coronoid in lingual (B2), lingual-dorsal (B3), and dorsal (B4) views. Note continuous dentary tooth row in normal left dentary (B1) vs. anterior end of coronoid overlaps and causes gap (indicated by double asterisks) in dentary tooth row in pathological right mandible (B2–B4). Images SEM micrographs (A) and photographs of specimens lightly dusted with ammonium chloride to enhance surface details (B).