Structure features and structural transformations of the maxillary bones in the Baikal cottoid fish

Abstract

In this paper, we study morphogeometric parameters and histostructure of maxillary bones in three coastal Baikal Cottoidei species belonging to different trophic groups. The results of the study revealed that the main trend in the transition from benthography to ichthyography is the sequential elongation of jaws and reduction in the mouth thrust accompanied by a consistent change in the form and internal structure of bone elements. A detailed analysis of data revealed that the changes mostly concern additional morphological structures (processes) of the bones directly connected with musculoligamentous apparatus and experiencing the highest tension during the functioning of the maxillary system. The distinctive features of the structural transformations maxillary bones in different fishes is a consequence of the uneven effect of power load that changes when the body adapts to certain habitat conditions.