Shape diversity in the trophi of different species of Rotaria (Rotifera, Bdelloidea): a geometric morphometric study

Rotifers have articulated hard jaws called "trophi", whose shapes are considered species-specific for monogonont rotifers but not for bdelloid rotifers. We present a geometric morphometric analysis of size and shape of bdelloid jaws, carried out on SEM pictures of trophi of nine morphospecies belonging to the genus Rotaria, using six landmarks. The study shows that trophi can also have species-specific form in bdelloids and suggests future directions for the analysis of the relationship between shape, size and diet in modelling trophi morphology during the evolution of Rotaria.