First record of Tridacna crocea Lamarck, 1819 (Bivalvia, Cardiidae) from Patnanungan Island, Philippines

Abstract

We present a new record and information on the distribution of the IUCN listed Tridacna crocea Lamarck, 1819 in the Philippines. The new record in Patnanungan Island extends the known distribution of this species by 80 km east of the nearest previously known occurrence. The collected specimens are found in shallow water at a depth of 3 m, exhibit a relatively small size, and showed the characteristic of completely burrowing its valves in coral substrates. DNA barcoding was also done, and the constructed phylogenetic tree demonstrated that the giant clams created a monophyletic group.  Tridacna crocea has a wide distribution and is relatively abundant throughout the Philippine reefs. We recommend updating the population status and stock assessment of giant clams in the country for local regulation and conservation management.