Shell average in size for the genus, large specimens measure up to 10.8 mm in largest diameter, most shells are however much smaller and around 7-8 mm in diameter. The color varies from pure white to pale cream. Outline oblique in shape. The sculpture of the valves consists merely of strong concentric lines. Towards the margins of the valves, most shells have numerous small knobs, as the remains of a sculpture of knobs which was an external shell layer. Most are clearly eroded off. The umbos are well raised above the cardinal area. On the inside of the right valve, the left side of the taxodont hinge has 7 teeth, the right side 8. There is a small indentation exactly below the beak. The muscle impressions are large on both sides. We refer to the photos for details on these characteristics. Shells are quite thick and solid, with a silky gloss all over.

Among the Bathyarca from the Indo-Pacific this species has a unique shape, combined with a shiny surface adorned with spaced concentric ribs. For the sake of completeness, we compare with Bathyarca kyurokusimana Nomura & Hatai, 1940 and Bathyarca nipponica Okutani, 1962. B. kyorukusimana can be distinguished at once by the presence of multiple radiating ribs on the outer surface, especially on both ends of the valves. These are absent in B. lucida n. sp. B. nipponica has a very rounded shape on the lower half of the valves: almost half a circle. The umbo is also much smaller and does not stick out much above the flat side of the upper part of the valves, while this is the case in B. lucida n. sp. B. nipponica is covered with a thick periostracum and the size is truly small: the holotype measures 3.7 mm. B. lucida n. sp. measures usually almost double that size and we never observed even traces of a periostracum in the new species.

TYPE LOCALITY
Mactan Island. Maribago. 500 m.
DISTRIBUTION
At present only known from the central Philippines: Mactan Island, Olango Island and Aliguay Island. This species is most common at great depth: between 250 and 500 m, but records go as shallow as 100 m.