This study examinespatterns of modularity or compartmentalization in the shells of Vivipara angularisfrom four populations collected from Lake Dapao at Pualas, Lanao del Sur, Philippines. A total of 120 points were used to outline the margins around the contour of the shell. Modularity and Integration Tool for morphometric data (MINT) software was used to determine compartmentalization or modularity and integration of the shell of V. angularis. Several models were hypothesized and results revealed that the shell of the V. angularis is divided into three distinct modules, namely: the spire, the body whorl and the aperture.It is hypothesized that these distinct modules built from each shell are said to be internally coherent but flexible in their relationships among one another.Since the same pattern of compartmentalization or modularity was observed among the four populations of V. angularis, this was argued to beindicating genetic conservatism in the shell morphology.
