Previous workers had proposed 21 different species names for the members of these five varieties, but they had examined only a few adults from a small region or a single site and had either not seen hybrids or had thought that they were distinct species. When scientists find that several former species are really only one, they apply the oldest available name to the single species. The oldest such name among the group of 21 former species was that of Harpalus somnulentus, a name proposed in 1829. This name was therefore given to the single species that now includes the 21 former ones. All the Wisconsin Harpalus pleuriticus and Harpalus fallax that had aroused my interest became Harpalus somnulentus.
Scientists commonly study tens of thousands of specimens from large areas.
Such large scale studies are the only method of obtaining correct conclusions about their identity. Such studies are also the only way to correctly determine their evolutionary history and to record their correct geographical distributions. Because of their considerable cost, such widespread studies are usually funded by grants from agencies such as the National Science Foundation. Grant funded research is also a major means for adding specimens to museum collections. For example, the various grant funded studies that I've done have added more than 39,000 specimens to our museum collections.