Polistes rubiginosus
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. "P. rubiginosus" is, however, extremely similar to "P. carolina", and can be found in the same regions; the key morphological difference being the malar area (the "cheek") seen from the side, but this works only for the female wasps. This area and the gena are covered in silvery pubescent hairs. "P. rubiginosus" is the only "Polistes" wasp in the "P. fuscatus"-group to have this characteristic, all other species have this area bare or almost so. Both sexes of "P. perplexus" can also be distinguished from "P. carolina" by the coarser transverse ridging of the propodeum. Distribution. This  species appears to be an endemic of the US. In 1979 Krombein states "P. perplexus" occurred from Maryland south to Georgia and from there west to southern Illinois, Kansas, Oklahoma and Texas. As of 2020 it has been recorded in the states of Arizona, Arkansas, Florida, Illinois, Kentucky, Louisiana, Missouri, Ohio, Oklahoma, Pennsylvania and Texas. The modern known distribution thus exceeds that given in Krombein in all directions because of problems with identification. The species very similar to "P. carolina" and may have been under-reported. The specimen from Arizona was collected in 1923 but only properly identified in 2016 . The first records from Florida date to 1989. The record from Pennsylvania is from 2005. The distribution largely overlaps with that of "P. carolina". Ecology. The ecology is poorly known because of the aforementioned confusion with "P. carolina". It is an eusocial insect, building nests in sheltered locations such as in hollow trees, or under wooden platforms and inside storage buildings. Adults have been seen feeding on "Euthamia graminifolia" and/or "E. caroliniana" in Florida. Conservation. The IUCN has not evaluated this species' conservation status. It has been recorded as present in the following protected areas: