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We report 35 molluscan species from Late Miocene cold-seep carbonates from the Amlang Formation in the Ilocos-Central Luzon Basin in Luzon Island, Philippines, collected in a large quarry in the province of Pangasinan. The 19 bivalve species are largely representatives of chemosymbiotic families; the six new species are the nuculid Acila (Truncacila) interferencia sp. nov., the mytilid Bathymodiolus labayugensis sp. nov., the thyasirid Conchocele pangasinanensis sp. nov., the lucinid Megaxinus gorrospei sp. nov., the vesicomyid Pliocardia ballesterosi sp. nov., and Sisonia frijellanae gen. et sp. nov., of uncertain taxonomic affinity. The 16 gastropods include one species restricted to seep deposits, the neritid species Thalassonerita hagai sp. nov.; the buccinid Enigmaticolus semisulcata represents the first fossil record of its genus. Biogeographically, the Pangasinan seep fauna shows several links to Neogene seep faunas in other tropical/subtropical areas, namely the Mediterranean and Caribbean regions. In contrast, shared taxa with nearby but extratropical Japan are few, as are shared taxa with Miocene seep deposits in New Zealand. [ABSTRACT FROM AUTHOR]

Neogene diversity history in the world center of biodiversity known as the Indo-Australian Archipelago (IAA) or the Coral Triangle remains poorly understood. Of particular interest is the recently reported Pliocene diversity jump that is considered to have established the present-day biodiversity level of the region needs rigorous inspections. We investigated Neogene fossil marine ostracods from Java, Indonesia and evaluate and test the Pliocene Diversity Jump hypothesis. We found a significant diversity increase from the late Miocene to the Pliocene, supporting the hypothesis. At the same time, there are considerable differences in depositional environments between the Miocene and Pliocene samples. Although it is unlikely that the main reason of the diversity increase is due to this paleoenvironmental difference, further samples and data from the IAA hotspot region are needed for more rigorous inspections. Our comparison between species-level and genus-level data indicated that species-level data are better to detect detailed macroevolutionary diversity histories, and genus level data are more useful for paleoenvironmental and paleoceanographic reconstructions. [ABSTRACT FROM AUTHOR]