An introduction to the naming conventions for shells
The scientific naming conventions can appear complicated and challenging to new collectors faced with writing labels for their shells. The following guidelines are intended to summarise the code of the International Commission on Zoological Nomenclature (ICZN) which covers all forms of animal life.
Scientific classification (taxonomy) is ever-changing with our developing understanding of evolutionary relationships but it is still based on the work of Linnaeus. He established a system assigning organisms to hierarchical divisions based on shared characteristics; it included kingdoms, classes and orders, though not all the divisions we know today. The main modern groupings are (from the largest down):
There is certainly not space on the label for all of these! But note here that the family groups are written with an initial capital letter in roman type.
For our purposes the important terms are the last two. Species names consist of two words in Latin (or derived from other languages that have been "latinised"). This two-part name or binomen is always written in italics. The first word refers to the genus (plural, genera) and always has an initial capital letter.
It is followed by the name of the species, which does not have an initial capital letter (even if it is derived from a proper name, as in our example).
The surname of the author who first published the description of the species and named it does not officially form part of the binomen, but it is good practice to include it on your label, since over the years different authors have erroneously used the same name for different species.
If there are two authors their names are separated by an ampersand, e.g. Terebra evelynae Clench & Aguayo, 1939. If there are more than two, you can just give the name of the first author followed by the abbreviation "et al.". Where authors have the same surname they may be distinguished by initials, e.g. A. Adams or C.B. Adams. If they have exactly the same name, Roman numerals may be needed to differentiate them, as in the case of George Brettingham Sowerby I, II and II.
Linnaeus himself is sometimes referred to by the name he took after he was ennobled (von Linné) and sometimes just abbreviated to "L." On this website, we prefer "Linnaeus" but in captions may use the abbreviation.
The author name is followed by a comma and the year of publication. In cases where a species has been reallocated to a different genus by later authors, the original author and date are enclosed in brackets, e.g. Cribrarula cribraria (Linnaeus, 1758). The author name and year are not italicised.
Some shell names may be more complex. Where a subgenus is involved its name should be in italics and placed in parenthesis after the genus name: it also has an initial capital letter, e.g. Oliva (Carmione) galeola Duclos, 1835.
Some species have subspecies, the name of which is placed after the species, in italics and without an initial capital letter. The following author and year refer to the subspecies publication, e.g. Conus biliosus meyeri Walls, 1979.
Other additions to the binomen can be used to identify recognised geographical varieties and colour forms of species or subspecies. On this website the abbreviation "f." (for forma) is placed after the species or subspecies name and in front of the form name; alternatively, only the form name is added, in quotation marks. No capitals are used (the ICZN does not cover taxonomic ranks below subspecies).
If the genus is known but the species has not been identified, the abbreviation "sp." (plural "spp.") in roman type can follow the generic name, e.g. Conus spp.
The common name for Conus tribblei is Tribble’s cone. It was named by Jerry Walls after his cat Tribbles. The cat had in turn been named after a fluffy alien organism in the TV series Star Trek. For further discussion of the strange thought processes that inform the choice of some shell names, see the article by Kevin Brown here, and this one by S. Peter Dance.
For more taxonomic and descriptive terms relating to shells, see the Glossary.