It was known for a long time as
P. perplexus, but in 2012 it was found that the older name
P. rubiginosus actually referred to this species; before that the name
P. rubiginosus was seen as a
synonym of
P. carolina. (said to have been published in 1870 in error in
Karl Vorse Krombein (1979) and Matthias Buck et al. (2008)). Cresson himself does not mention
P. carolina, but states that he found
P. perplexus very closely resembling
P. rubiginosus, also recognised as a species in his time, and perhaps just to be a male form of this taxon. He also described
P. generosus as a new species in the same paper, from three specimens from Texas, stating that it "may be an extreme variety of
perplexus".
P. generosus was published on the next page after
P. perplexus, which means that when the two taxa were considered synonym,
P. perplexus had
taxonomic priority because it was published first.
Owain Richards saw it as a synonym of
P. carolina in 1978, although Wade and Nelson recognised it as a species in a paper published the same year. Thus the
taxon was for a long time, and until relatively recently, confused with
P. carolina. ==Description==