The collection of deep-sea pebble crabs (Leucosioidea) during the BIOPAPUA Expedition, comprising 8 species, including a species new to science, is significant because although the previously described species had not been recorded from the Bismarck and western Solomon Seas, they occurred in at least one nearby location (New Caledonia, Vanuatu, Solomon Is). Praebebalia fungifera sp. nov. is described and illustrated. It differs from its closest congener, P. septemspinosa Sakai, 1983, in bearing fungiform granules dorsally on carapace, shorter chelipeds, the relatively stout male first gonopod with a preapical row of setae and the beak-like tip, as compared to the rounded granules dorsally on the carapace, greatly elongate chelipeds and the slim, elongate, distally curved gonopod of P. septemspinosa, preapically set with very long setae and a hook-like tip.