Bayerotrochus westralis, commonly known as "Australia's split shell", is a species of sea snail, a marine gastropod mollusk in the family Pleurotomariidae.

The aperture is oval, the slit is positioned roughly one third of the way between the upper and lower sutures and is relatively long, about 19 percent of the circumference.

Occasionally the teleoconch (body whorls) are overlaid with pale orange or pink axial flammules.

The selenizone has no distinct spiral sculpture however it has numerous fine curved growth striae.

[2] This species has been typically found on soft muddy bottoms between 250 and 500 meters in a small area off Western Australia south of Broome and northwards to the Ashmore Reefs,[2] off southern Japan and in the Central Indo-West Pacific.