A new symbiotic palaemonid shrimp Platypontonia ngae sp. nov., is described based on a male-female pair found inside the mantle cavity of a gastrochaenid bivalve mollusk collected on a coral slope on the island Panglao, Philippines. The new species constitutes the third member of the genus Platypontonia Bruce, 1968. The new species is described, figured and compared with its congeners.