Polistes rubiginosus is one of two species of red paper wasp found in the eastern United States (the other being Polistes carolina) and is noted for the coarser ridges on its propodeum. It is a social wasp (subfamily Polistinae) in the family Vespidae. Until taxonomic revision by Matthias Buck in 2012, P. rubiginosus was long known under the name P. perplexus. It occurs northernmost from Maryland, Pennsylvania to northern Ohio, south to Florida, and from there west to central Illinois, Kansas, Oklahoma, Texas and Arizona. Taxonomy 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. P. perplexus was named in 1872 for six specimens collected in Texas by Ezra Townsend Cresson (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 The length of the forewing is 18.0–21.5 mm in the female, 17.0–18.0 mm in the male. The body of the creature is almost entirely rusty red, broken by a number of black to dark brown markings. These markings consist of a usually well developed spot around the eyes, this rarely divided into individual spots around each eye, and often a spot in front of pronotal carina. In some cases there are yellow markings on the propodeal valves and tarsi. Polistes rubiginosus and P. carolina are the only large red-coloured wasp species in the eastern US.