A remarkable specimen of Bayerotrochus teramachii, commonly known as Teramachi’s Slit Shell, belonging to the highly distinctive Pleurotomariidae family.

Measuring 106 mm, this specimen displays the characteristic broad, rounded form of the species, with a beautifully stepped spire and the unmistakable slit along the outer lip. The surface is covered with extremely fine, regular spiral sculpture, producing an elegant silky texture and enhancing the shell’s warm golden, cream and pale beige coloration.

Bayerotrochus teramachii is a deep-water species occurring in Japanese and neighbouring western Pacific waters. It typically inhabits relatively deep sandy or gravel bottoms and is particularly appreciated by collectors for its unusual primitive morphology and refined surface sculpture. Members of the Pleurotomariidae are often referred to as slit shells, a lineage represented in the fossil record for hundreds of millions of years.

The combination of its substantial size, delicate natural patterning and unmistakable architectural form makes this an especially attractive specimen for a serious shell collection or natural-history display.