Meeting Abstract
Etroplinae and Ptychochrominae represent two subfamilies of the highly diverse family Cichlidae. Occurring in Madagascar and South Asia, these groups are less species rich and much less studied than their relatives in the Neotropics and Africa. Our research focused on understanding the relationship between overall body shape, which varies from deep to shallow-bodied, and oral jaw shape. We used geometric morphometrics to evaluate shape variation among species for both the body and the jaw. Jaw shapes were approximated using the oral jaw four-bar linkage, which is often used as a model for jaw mechanics in teleost fishes. Although the ptychochromines displayed a larger overall range of body forms, variation in etroplines was similar and parallel in direction. A significant relationship was found between body and jaw shape in Etroplinae, but not in Ptychochrominae. Our results suggest that while body shape evolution may have influenced jaw form, it did not appear to impact its functionality (as measured by maxillary kinematic transmission, MKT). Overall, research of this nature is necessary for a better understanding of the evolution and diversity exhibited in two groups that include a number of endemic species, many of which are rare or even extinct.
