A new species, Adelpha margarita Willmott & Hall, new species, is described from Andean cloud forest habitats from southern Ecuador to Bolivia. Adelpha margarita garleppi Willmott, new subspecies, is described for southern Peruvian and Bolivian individuals, which differ from the nominate subspecies in having complete orange postdiscal bands on the dorsal surface. The new species differs from related species in the Adelpha serpa group in wing pattern, DNA sequence data and habitat. A lectotype is designated for Adelpha seriphia therasia Fruhstorfer, because the type series of this name contains individuals of both A. seriphia and A. margarita. Neighbor-joining and maximum parsimony analyses of 579 bp of the mitochondrial cytochrome oxidase I (COI) ‘barcode’ region, for 27 Adelpha specimens representing 9 species and 13 taxa, suggest that the closest relative to A. margarita is the Central American to west Andean taxon A. seriphia godmani Fruhstorfer. The DNA sequence data, coupled with a re-analysis of museum specimens, suggest that Adelpha godmani should be treated as a distinct species (revised status). Finally, a new subspecies, Adelpha justina pichincha Willmott & Hall, new subspecies, is described from Pichincha province in western Ecuador.

Phaneta comprises a large genus of Nearctic tortricids with several species that are difficult to delimit using morphological characters. We examined Phaneta tarandana (Möschler 1874) and P. montanana (Walsingham 1884), using morphology and DNA. Our results upheld the distinction between these two species, even though the wing coloration and male genital characters traditionally used to diagnose them were unreliable due to intraspecific variation. Nonetheless, a combination of forewing fringe scale detail, wing streaks, mitochondrial, and nuclear DNA delimited these moth species in a region of overlap in western Canada.

The genetic compatibility of the greater fritillary butterflies was tested through hybrid crosses made between the North American genus Speyeria and the Eurasian genera Argynnis and Mesoacidalia. Numerous hybrid crosses made between A. paphia and Speyeria failed to produce any viable progeny, but a hybrid male was successfully produced between M. aglaja and S. nokomis. The genetic compatibility and divergence of Speyeria species was tested through hybrid crosses and back-crosses among the various species. All species of Speyeria appear to be inter-fertile in hybrid crosses with the exceptions of the two most divergent species, S. idalia and S. diana, that produce non-viable hybrid females and sterile hybrid males. As a consequence, it is postulated that inter-species gene flow through hybridization accidents in nature has been important in the past evolutionary history of this genus, and is partly responsible for the absence of consistent, non-overlapping diagnostic taxonomic characters among most species of the genus.

The nominal taxon Hesperia illinois Dodge, 1872 (now recognized as Euphyes bimacula illinois) was described from over 40 specimens collected in Bureau County, Illinois, by the brothers Edgar and George Dodge. Since 1999, H. illinois has been represented by a neotype from Grundy County, Illinois, but this designation is nomenclaturally invalid for technical reasons. In addition, at least three syntypes of H. illinois exist. A lectotype is designated, thereby returning the type locality to Bureau County, Illinois.

A new species of leaf-mining moth, Caloptilia triadicae, is described from the southern United States from Florida to eastern Texas. Larvae of this moth are known to feed preferentially and at high densities on the Chinese Tallow tree, Triadica (= Sapium) sebifera (L.) Roxb. (Euphorbiaceae), a tree first introduced into Georgia in 1772 from Asia, which has since become an invasive plant species of grave concern over much of the southeastern United States and California. Caloptilia triadicae is also known to feed rarely on Gymnanthes lucida Sw. (Euphorbiaceae), a tree not known to occur in the Old World but native to Florida, the Bahamas, the Caribbean, and Central America. Because of the origin of the preferred host and the morphological affinities of the moth to the Chinese species, Caloptilia hamulifera Liu and Yuan, it appears likely that C. triadicae also originated from Asia. The larvae of Caloptilia are hypometamorphic and possess two distinct larval body forms and feeding behaviors—an early stage sap-feeding form with a flattened body and prognathous mouthparts and a later stage tissue-feeding form with a more cylindrical body and possessing hypognathous mouthparts. The sap-feeding larvae initially construct long, serpentine, subepidermal mines on the upper (adaxial) leaf surface. After developing to the tissue-feeding form, the larva of C. triadicae leaves the mine and crawls to the edge of the leaf and cuts a narrow strip of leaf which is rolled into a tight coil. It continues feeding externally on the leaf inside the roll in which it eventually forms a silken cocoon for pupation.

The coral bean, Erythrina herbacea, is reported as a new host for Automeris io in north-central Florida, based on a single batch of larvae found on this plant in nature and reared through on it in the laboratory. However, the consequent laboratory rearing showed a high cost associated with using this host plant. The mortality of young larvae of the F-2 generation reared on E. herbacea was very high (over 90%), and much higher than that of control larvae, which were reared on mature leaves of Quercus nigra (14–38%). The leaves of E. herbacea, known for their toxic alkaloids, were extracted with methanol, made into a water solution, applied on the mature leaves of Q. nigra, and fed to 1st instars of A. io. This produced no negative effect on the caterpillars. While the mature leaves of Q. nigra produced low mortality in young caterpillars, the young terminal leaves of this plant were as lethal to A. io as leaves of E. herbacea. Additionally, it was noted that rearing larvae on E. herbacea (a diet with a higher N2 content) led to faster larval development and smaller adult moths. The A. io larvae in this study developed during 63–100 days and underwent seven larval instars, which contradicts many popular accounts of the fifth instar being the final in A. io. Finally, Prunus angustifolia proved to be an unsuitable hostplant for A. io, as feeding on this species led to the arrested development of larvae and their eventual death.