Lacertidae

Villa, Andrea & Delfino, Massimo, 2019, A comparative atlas of the skull osteology of European lizards (Reptilia: Squamata), Zoological Journal of the Linnean Society 187 (3), pp. 828-928 : 854

publication ID	https://doi.org/10.1093/zoolinnean/zlz035
persistent identifier	https://treatment.plazi.org/id/9C298799-D25B-5A20-FC87-FA612453ABD4
treatment provided by	Plazi
scientific name	Lacertidae
status

Treatment

Lacertidae View in CoL View at ENA ( Fig. 16E–L View Figure 16 )

In the jugal of lacertids, the anterior process can be narrow and pointed (most species; Fig. 16I–L View Figure 16 ), moderately large, flattened and more rounded anteriorly ( Ac. erythrurus ; Fig. 16E, F View Figure 16 ) or moderately large, flattened and anteriorly forked ( Ophisops elegans ; Fig. 16G, H View Figure 16 ). The lateral surface of the anterior portion of this process is largely covered by the articulation surface with the posterior process of the maxilla ( Fig. 16I, K View Figure 16 ), except for Ac. erythrurus and Ophisops elegans , in which this surface is narrow and the bone is more laterally exposed ( Fig. 16E, G View Figure 16 ). In species in which either a step or a spur is present on the dorsal margin of the posterior process of the maxilla (see above), the articulation surface on the jugal recalls the stepped and spurred morphology, respectively. The palatal process is present: it is weakly developed in Ac. erythrurus ( Fig. 16F View Figure 16 ), E. arguta and Ophisops elegans ( Fig. 16H View Figure 16 ), and moderately to well developed in other species ( Fig. 16J, L View Figure 16 ). A distinct medial process is present in Ophisops elegans ( Fig. 16H View Figure 16 ) and Psammodromus ( Figs 16J View Figure 16 , 17A View Figure 17 ), but a poorly developed one ( Fig. 17B View Figure 17 ) can be also present in other genera [e.g. Podarcis , as also reported by Blain et al. (2007)]. The posterodorsal process is narrow and pointed. Proportions of the anterior and posterodorsal processes differ within species: the anterior one is the longest in Algyroides , Da. oxycephala , Di. mosorensis , Lacerta agilis , Lacerta bilineata , Lacerta schreiberi , Lacerta viridis , Ophisops elegans , Po. siculus , Po. tauricus , Po. tiliguerta , Po. waglerianus , Psammodromus algirus , Z. vivipara and some specimens of Po. muralis ( Fig. 16G–J View Figure 16 ), the posterodorsal one is the longest in Ac. erythrurus and E. arguta ( Fig. 16E, F View Figure 16 ), whereas they have roughly the same length in Ar. bedriagae , H. graeca , I. bonnali . I. cyreni , I. horvathi , I. monticola , Lacerta trilineata , Po. bocagei , Po. filfolensis , Po. hispanicus , Po. lilfordi , Po. melisellensis , Po. milensis , Po. pityusensis , Ti. lepidus and some specimens of Po. muralis ( Fig. 16K, L View Figure 16 ). A certain degree of ontogenetic variation can be present, as demonstrated by Ti. lepidus NHMW 625, a very young individual whose anterior process is clearly longer than the posterodorsal one ( Fig. 18 View Figure 18 ). The quadratojugal process can be absent ( Ac. erythrurus and Ophisops elegans ; Fig. 16E–H View Figure 16 ), weakly developed ( I. horvathi , Po. pityusensis , Po. tiliguerta and Psammodromus algirus ; Fig. 16I, J View Figure 16 ) or well developed (other species; Fig. 16K, L View Figure 16 ). Its development may vary during ontogeny, being more developed in juveniles and less developed in adults (e.g. Psammodromus algirus ; Barahona & Barbadillo, 1997). The lateral surface of the ventral portion of the bone can be covered, at least in large specimens, by a moderately to well-developed dermal ornamentation (absent in Ac. erythrurus , Algyroides , Da. oxycephala , Di. mosorensis , E. arguta , H. graeca , I. bonnali , I. cyreni , I. horvathi , I. monticola and Ophisops elegans ). A moderately large foramen opens on the medial surface of the jugal, at the meeting point of the anterior and the posterodorsal processes.