Assessing Taxon Names in Palynology (II): Indices to Quantify Use of Names

ABSTRACT A major and recurrent issue in nomenclature and taxonomy is synonymy and the occurrence of competing names for a taxon. Formal proposals for conservation, protection, or rejection of names are a painstaking but necessary work, which for extant plants, often requires consulting the frequency of use of competing names in floras. In palaeopalynology, such information can be gathered by tedious consultation of the literature or by working with palaeopalynological databases, which provide easily accessible quantitative data on how frequently each given taxon name is used. Here, we show that such information can be employed not only for taxonomic revisions in plant microfossils, but also to calculate three new simple metrics, i.e. Citation Share (CS), Citation Rate (CR), and Establishment Index (EI), and quantify how widespread the use of a name is on its own, or in comparison to potentially competing name(s). Using three case studies, we demonstrate how our proposed metrics can easily be used to present how the use of a name of a taxon changed over the decades, especially for competing names. Independently of the study question, our proposed metrics provide a fast overview of popularity of names and abundance of the respective taxa in species inventories (CS and CR), and a concise compound metric to represent the standing of a name for competing names today (EI). Their advantage is that they encode information that would otherwise require rather lengthy enumerations and space-consuming visual representations. They are therefore an effective tool to represent data in a short and concise way to clarify cumbersome taxonomical and nomenclatural problems, and can support informed proposals for either conservation, protection or rejection, which are typically very limited in space for the respective argument.