The Cardiidae of the Panglao Marine Biodiversity Project 2004 and the Panglao 2005 Deep-Sea Cruise with descriptions of four new species (Bivalvia)

Sixty-three Cardiidae species (including Tridacninae) sampled by the 2004 Panglao Marine Biodiversity Project (PMBP) to Panglao, Philippines, and the PANGLAO 2005 Deep-Sea Cruise are described. In addition, Cardiidae species lists of the Philippine Cuming Tour 2005 and AURORA 2007 expedition are provided. Four species are new to science: Fragum grasi spec. nov., Frigidocardium helios spec. nov., F. sancticaroli spec. nov. and Microcardium velatum spec. nov. For the following six species this paper includes the first published records for the Philippines: Acrosterigma dianthinum (Melvill & Standen, 1899), F. torresi (E.A. Smith, 1885), Fulvia (Laevifulvia) subquadrata Vidal & Kirkendale, 2007, Microfragum erugatum (Tate, 1889), M. subfestivum (Vidal & Kirkendale, 2007) and Vasticardium sewelli (Prashad, 1932). Indo-Pacific range extensions for several other species are given. Ecological data support assignment of Afrocardium to Orthocardiinae. Cardium (Ctenocardia) victor Angas, 1872 and Cardium bomasense Martin, 1917 are transferred to Freneixicardia, the former being the sole extant representative of the genus, and of which Cardium (Trachycardium) hulshofi Pannekoek, 1936 is a new synonym. Based on shell morphology, it is shown that the current variously adopted generic assignments of Cardium lobulatum Deshayes, 1855, C. attenuatum G.B. Sowerby 2nd, 1841, C. biradiatum Bruguière, 1789 and C. multipunctatum G.B. Sowerby 1st in Broderip & Sowerby 2nd, 1833 are unsatisfactory. As a consequence, the alleged Indo-Pacific presence of the genus Laevicardium is questionable. Fulvia (Laevifulvia) imperfecta Vidal & Kirkendale, 2007 is a new synonym of "Laevicardium" lobulatum Deshayes, 1855. Habitat preferences of the taxa encountered during PMBP 2004 are defined, based on four main macro-habitat categories. SEM photos, showing the early ontogenetic stages, demonstrate markedly allomorphic growth of some taxa. Description of the process of development to the terminal shell shape provides a more complete species concept and rigorous species delimitation.