Figure 15 in A comparative atlas of selected skeletal elements of European urodeles (Amphibia: Urodela) for palaeontological investigations

Figure 15. Precaudal vertebrae of Ichthyosaura (A, B) and Lissotriton (C, D), as an example of the intrageneric variation of the posterodorsal area of the neural arch. Notice that in A and C, the posterodorsal area is vertical and followed by the forked neural crest, whereas in B and D the posterodorsal area is roof-shaped, and the neural crest terminates in the middle of the incisura dorsalis. In contrast, the medial edges of the prezygapophyses (dashed lines in A, C) are a less variable character (divergent in the case of Ichthyosaura and parallel in Lissotriton; see diagnoses section). Scale bars: 1 mm.