Catalogus

The following 98 discussions of often-complex name changes involve 348 species-group names and their subsequent spellings, 231 of which were introduced by Lea. Based on their current taxonomic status, the names belong to 4 bivalve and 11 gastropod families, with the vast majority concentrated in Unionidae and Pleuroceridae. Under the current ICZN Code, the investigated changes fall into many different categories, which impacts their nomenclatural availability: 35 names changed by Lea (plus 6 by other authors) are interpreted as substitute names for junior primary homonyms, 7 of which were unnecessary; 1 name (plus 6 by others) as substitute names for junior secondary homonyms, 1 of which was unnecessary; 13 names as justified emendations; 10 names (plus 1 by another) as unjustified emendations that have not entered prevailing usage; 1 name determined by his first reviser action; 37 names (plus many by others) as incorrect subsequent spellings that are not in prevailing usage; and 1 incorrect subsequent spelling that is shown to be in prevailing usage and thus considered a correct original spelling. The concept of “prevailing usage,” ill-defined under the current (1999) ICZN Code, is addressed in this context. The following names in current use are corrected as follows: Helix balasteriana I. Lea, 1840 (taxon inquirendum, ?Dyakiidae), Lioplax cyclostomatiformis (I. Lea, 1844), Diplodon demararaensis (I. Lea, 1859), Iheringella isocardiodes I. Lea, 1856, Dilatata brongniartiana (I. Lea, 1843), Elliptio nasutidus (I. Lea, 1863), Elliptio pullata (I. Lea, 1857), Pleurocera picta (I. Lea, 1841) [instead of P. curta (Haldeman, 1841), which is preoccupied] and Beringiana youconensis (I. Lea, 1847); many others are confirmed in their recently applied spellings. This work serves as an example that the basic endeavor of summarizing available and valid names from the published literature is not always a straightforward task.