Patterns in species description: a case study using the Geometridae (Lepidoptera)

Abstract

The described fauna is not a random sample of extant species. However, patterns in species description remain poorly documented. In this paper we explore the dynamics of description of geometrid moths, one of the most speciose families of Lepidoptera. The numbers of species described per decade peaked around 1890 to 1910, and the cumulative number of described species has yet to reach an asymptote. Growth in the cumulative numbers of described species has taken a variety of forms in the different biogeographic regions. The distributions of the numbers of authors describing different numbers of species, and of the numbers of synonyms per valid species name, are both strongly right-skewed. The number of synonyms associated with a valid species name is negatively correlated with the year in which that name was published, and the numbers of synonyms and valid species names are positively correlated both across subfamilies and biogeographic regions. Such patterns provide an important foundation from which to explore underlying spatial patterns in the species richness of speciose higher taxa.