Determination of a new spring-flying species of the Pterourus glaucus complex (Papilionidae) in southern New England

Recently, a bimodal emergence pattern was identified in populations across a regional band stretching from southern New England, through central New York (Hagen & Lederhouse, 1985), northeastern Pennsylvania (Monroe & Wright, 2017) and into southern Ontario (Schmidt, 2020). This bimodal pattern encompasses two univoltine taxa: an earlier, spring-flying taxon with slightly closer morphological affinity to canadensis; and a later, summer-flying taxon with a closer affinity to glaucus.

The early-flight taxon is here described as a new species, most likely of hybrid origin similar to appalachiensis. The late-flight taxon, tentatively referred to as the “Mid-Summer Tiger Swallowtail” (Wang, 2017; Schmidt, 2020), also likely of hybrid origin, appears to be undergoing rampant hybridization with glaucus in southern New England, though there is evidence it has achieved early stages of speciation in Ontario.

Additional key words: Rhode Island, Massachusetts, Connecticut, bimodal flight, early-flight, late-flight, hybrid introgression, Eastern Tiger Swallowtail, Canadian Tiger Swallowtail, New England Tiger Swallowtail, Mid-Summer Tiger Swallowtail, Björk Guðmundsdóttir, bjorkae. ZooBank registration: urn:lsid:zoobank.org:pub: 583A49FC-2C69-478F-8BE7-3F3BCCFAD46E