Bivalves and gastropods of Tubbataha Reefs Natural Park, Philippines

in this study of marine bivalves and gastropods of Tubbataha Reefs Natural Park (TRNP), Palawan, Philippines, we photo-document 96 species, including 17 species of bivalves (in seven families), and 79 species of gastropods (in 29 families). Of these, 64 species (eight bivalves and 56 gastropods species) were new recorded from the park. The list also includes the seven species of giant clams which are protected under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and three nationally protected gastropod species (Cassis cornuta, Charonia tritonis and Tectus niloticus). Thirty-six species that were previously reported at the park were not found in this study, which suggests that there are at least 132 species of gastropods and bivalves at TRNP. Our observations were limited at intertidal and shallow subtidal reefs in the park, suggesting that the number of species in the list may rise with an extensive survey.


INTRODUCTION
The Tubbataha Reefs Natural Park (TRNP) in the middle of the Sulu Sea, the Philippines, is rich in biodiversity.in 1993 the park was named by the United Nations, Educational, Scientific and Cultural Organization (UNESCO) as a World Heritage Site, and research has been done to document and protect the rich flora and fauna.Currently there are ca.400 species of corals (85% of known coral species in the Philippines), nearly 700 species of fish, two species of marine turtles, seven species of breeding seabirds, 13 species of cetaceans, 79 species of algae and 10 species of seagrass (Dygico 2006;Songco 2012;TMO 2013).
Although many taxa have been inventoried in TRNP, not much is known about the park's molluscan fauna, which Yamaguchi (1996) first documented.Other studies did not extensively focus on mollusks but reported a few species (see Estacion et al. 1993;Dolorosa and Schoppe 2005;Dolorosa et al. 2011;Dolorosa and Jontila 2012;Dolorosa et al. 2013).We include previously published data, along our new observations made between May 2005 and June 2010, to provide an updated list of the mollusks of TRNP.Given such meager information, this list of mollusks in TRNP is hoped to complement all other information about the rich and undocumented diversity in the Islands of Palawan, Philippines.

MATERIALS AND METHODS
This species list of mollusks of TRNP is based on photos made within TRNP, Palawan, Philippines (08°43′-08°57′ N and 119°48′-120°03′ E), during annual biodiversity monitoring between May 2005 and June 2010.The TRNP is a no-take zone, and for this reason, no voucher specimens were collected.Photos of bivalves and gastropods were identified with the aid of various reference materials (Springsteen and Leobrera 1986;Aubry 1999;Abbott and Dance 2000;Laureta 2008;Terryn 2007;Poppe 2008a;Poppe 2008b;Poppe 2010a;Poppe 2010b).The species' taxonomy, including the species reported in prior publications, is according to the World Register of Marine Species (WoRMS 2014).Species are alphabetical within families.Also included in this list of species are those previously published in the literature but not encountered in our study.

RESULTS
We photo-document 96 species of mollusks from TRNP; 17 of these are bivalves belonging to seven families (Table 1; Figures 1 and 2).We newly record eight bivalves from the park (Table 1).We observed 79 species of gastropods, and 56 of these are new records at TRNP (Table 2; Figures 3-7).

DISCUSSION
The total number of species (96 species) recorded in this study is much higher compared with the previous record of Yamaguchi (1996) (Tables 1 and 2).However, 36 of the previously reported species were not found, implying that there are at least 132 species of gastropods and bivalves in TRNP.
Among the recorded species, seven bivalves (Tridacninae) are CITES protected (CITES 2014) and three gastropod species (Charonia tritonis, Tectus niloticus, and Cassis cornuta) are protected in the Philippines (Dolorosa and Jontila 2012;Dolorosa et al. 2013).These large mollusks species have high economic, ecological, aesthetic and scientific importance but are becoming rare in many parts of the country; thus, TRNP

LISTS OF SPECIES
can serve as significant seed source of these valuable species.
The number of species of gastropods and bivalves recorded from such a rich and protected area within the Coral Triangle, the world's center of marine biodiversity, is very low considering that Springsteen and Leobrera (1986) reported more than 1,600 species of mollusks from the Philippines.Previous studies were limited to intertidal areas (e.g., Batomalaque et al. 2010, who had reported 100 species).Our study was undertaken in intertidal and shallow subtidal coral reefs and sandy habitats and focused mainly on largeshelled species (over ca. 2 cm) and neglected smaller.The deeper water sandy areas inside the lagoon and the ca.1000 m abyss surrounding the reefs remain unexplored.A deep sea expedition in Panglao, Bohol, Philippines found about 6,000 species (Richer de Forges et al. 2009), which include new species and new records for the Philippines.We anticipate that continued exploration of TRNP in both shallow and deep water habitats and with small-bodied species targeted may reveal new records for the park, Palawan, and the Philippines.

ACKNOWLEDGMENTS
This study is an offshoot of several years' of annual monitoring within TRNP, with funding from the Tubbataha Management Office, Conservation International, and World Wildlife Fund for Nature.We thank U. Aubry and J. Sarino for confirming some identifications.L. Creencia read an early draft of the manuscript.The comments of the two anonymous reviewers are greatly acknowledged.

Table 2 .
Gastropod species from Tubbataha Reefs Natural Park, Philippines;  = recorded;  = previously recorded but not found this study;  = new ecords, this study.