Giant clams are ecologically important, benefitting species of all trophic levels. But numerous populations have declined drastically in numbers due to past intensive exploitation that led to their listing in both CITES Appendix II and IUCN Red List of Threatened Species.. However, giant clams are notoriously difficult to identify, and recent molecular work has revealed that morphological misidentification of giant clams have confounded current population assessments and extinction risk.  The most recent study of the status of giant clams in the Samoan Archipelago was published in a journal over 20 years ago, without molecular corroboration of visual identifications. Using morphologic characteristics and ezRAD genetic techniques, we identify the existence of Tridacna noae in the Samoan Archipelago, presenting the first observation and a resulting range expansion. Accurately identifying the extant species in the archipelago is the first step towards a much-needed population status assessment to effectively manage these long-lived species.

Giant clams of the subfamily Tridacninae are conspicuous members of Pacific coral reef communities that play such important ecological roles that some authors have considered them as keystone species (Guibert et al., 2020; Mamat et al., 2021). All species of Tridacninae are of widespread conservation concern and are listed on both the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and the International Union for Conservation of Nature (IUCN). However, giant clams are notoriously difficult to identify, and recent molecular work has revealed that morphological misidentification of giant clams have confounded current population assessments and extinction risk

Giant clams are keystone species on coral reefs, but global demand for their harvest has decimated populations and resulted in all Tridacnids being listed on both CITES and IUCN lists. However, giant clams are notoriously difficult to identify, and recent molecular work has revealed that morphological misidentification of giant clams have confounded current population assessments and extinction risk. The most recent study of the status of giant clams in the Samoan Archipelago was published over 20 years ago, without molecular corroboration of visual identifications. Using morphologic characteristics and ez-RAD genetic techniques, we identify the existence of Tridacna noae in the Samoan archipelago, presenting the first observation and a resulting range expansion. Accurately identifying the extant species in the archipelago is the first step towards a much-needed population status assessment to effectively manage these long-lived species.