Teeth number variation and cranial morphology within <em>Vipera aspis</em> group
The huge morphological variability of asp viper (Vipera aspis) snakes has been longly addressed and studied to solve systematic and phylogeographic questions, with emphasis mainly to external morphology, distributive patterns and genome analyses. Teeth number and skull size variation are presently considered in order to contribute to the definition of the morphological puzzle that characterise the asp viper, comparing these structures among age classes and subspecies. The results indicated that, on the whole, 1) teeth number did not vary between sexes, 2) right palatine, total palatine and right dental teeth number varied among taxa and 3) skull length was markedly dimorphic. These differences apparently are congruent to taxonomic position
and published phylogeographic patterns.