This continuously updated registry lists world record shell sizes (given in mm). The 15th edition contains over 8,000 changes since the last edition, for a total of over 22,600 records.
Size continues to be an issue among shell collectors and researchers. Though some may view this project as a competition of sorts, it remains the goal of the Registry of World Record Size Shells to provide collectors, researchers, and students of malacology and conchology with a single source document for the maximum (and, in some cases, the minimum) adult size attainable by shell- bearing marine molluscan species of the world. Some families, although shell producing, have been omitted because of subjectivity in obtaining reproducible measurements of species contained within those families.
The scope of the Registry is purposely limited to data intended as support information for each species entered. Categories selected for inclusion are based on, but not limited to, those included in past publications by other authors of similar works. Additional categories not included in earlier publications have been added to this issue of the Registry based on the areas of interest most often expressed by readers and reviewers.
The alphabetic format for the Registry was selected for its ease of use by the widest possible and audience. Taxonomic placement of entries under respective families is based on A Classification of the Living Mollusca and Bouchet & Rocroi, 2006. It is not the intent of the Registry to propose correct taxonomic placement or dispute synonymies, although a concerted effort has been made to make the information contained in the Registry conform to currently published opinion.