Morphometric analysis for taxonomic assessment of Cypraeidae species in Alaminos, Pangasinan, Philippines

Abstract

The family Cypraeidae, commonly known as cowrie shells, is a significant group in the Phylum Mollusca. They have colorful shells with narrow, elongated apertures bordered by teeth, and they are prevalent in the marine environments of the Indo-West Pacific region, including the Philippines. The phylogenetic relationships within this family have been challenging due to their high morphological variability and limited molecular data. Given the need to resolve taxonomic uncertainties in this group, complexities arise when investigating their morphological variation, as their morphological variability, along with the existence of cryptic species that are morphologically similar but genetically distinct, complicates the delineation of species boundaries and phylogenetic relationships. These patterns of morphological variation can lead to misclassifications and uncertainties in taxonomic assignments, impeding efforts to establish an accurate taxonomy for cowries. One of the methods that can be used to address this issue is morphometric analysis. It is a widely used tool to elucidate shape variations, evolutionary patterns, and ecological adaptations across diverse animal taxa. Thus, in this study, the morphometric analysis for variation of the family Cypraeidae in the intertidal areas of Brgy. Telbang and Brgy. Victoria, Alaminos Pangasinan, Philippines was assessed. A total of 143 individuals were collected, belonging to five different genera (Lyncina, Cypraea, Monetaria, Staphylaea, and Erronea). Observation among this population showed significant differences in the shell morphology, specifically in their shell patterns, shapes, and sizes. Incorporating morphometric techniques allows for the quantification of subtle variations in their shell morphology, providing valuable information on evolutionary relationships, species diversification, and ecological adaptations within this diverse group of gastropods.