Seven new species of the Aleiodes pilosus-group (=Tetrasphaeropyx Ashmead) are described and a key is provided for all known Canadian species in this group, as well as a new species found in North and South Dakota that is similar to one of the new Canadian species. Species described are as follows: A. argyllacearia, A. crassijugosus, A. dakotensis, A. dissiticarina, A. huberi, A. secwepemc, and A. sexmaculativorax. Species previously described and included in this key are A. anatariatus Fortier (2007), A. cartwrightensis Fortier (2007), A. halifaxensis Fortier (2007), and A. provancheri Fortier (2007).

The mayfly fauna of Washington consists of 109 species in 38 genera among 12 families. Previous and new data (from 22 major collections) are given for all species and include new state records for 45 of the species, and the first published data for 57 species. In addition, 725 new county records involving 38 of the 39 state counties are given for 91 of the species.

The mayfly fauna of Oregon consists of 142 species in 45 genera among 11 families. Previous data and new data (from 20 major collections) are given for all species and include first published state data for 52 of the species. In addition, 977 new county records involving all 36 Oregon counties are given for 117 of the species.

The nymphs of two uncommon stonefly species Calileuctra dobryi Shepard & Baumann and Haploperla chilnualna (Ricker) are described and illustrated from correlated and reared specimens collected from California streams from 2004 to 2006. The diagnostic characters of these nymphs of both species affirm the nymphal generic characters for Calileuctra (Leuctridae) and Haploperla (Chloroperlidae) proposed by Stewart & Stark (2002). Absence of Calileuctra dobryi in interrupted and intermittent streams in drought years suggest that it is capable of having extended egg diapause and flexible univoltine to semivoltine life cycles similar to some species of Zealeuctra.

A new species of Nepalomyia Hollis, 1964, N. nantouensis, is described from Taiwan. Further record of a recently described Taiwanese species, N. horvati Wang and Yang, 2004, is also included. A key is given for the species from Taiwan.

A new species of Ischiolepta, I. biuncialis sp. nov., is described. A key to the species of the genus from China is presented.

Two new species of Diostracus from China, D. clavatus and D. longicercus, are described. A key to 21 known species of the genus from China is given.

The identification of Addyme-Calguia-Coleothrix complex is clarified. One species, Coleothrix longicosta, is described as new to science, Calguia obscuriella (Inoue) is transferred to Coleothrix Ragonot, and Addyme inductalis (Walker) and Calguia defiguralis Walker reported by Inoue and Roesler et al. are listed as misidentifications.

A new Hercostomus species group, crassivena-group is established. The species of the group are reviewed and keyed. A new species, Hercostomus huaguoensis sp. n., is described.

Two new Plagiozopelma species are described: P. biseta n. sp. and P. flavidum n. sp. A key to species of the genus from China is given.

Chilemutilla Cambra and Quintero (Sphaeropthalminae), a new genus of nocturnal Mutillidae is described and illustrated based on the following six new species from northern Chile: C. aielloae n. sp., male; C. aptera n. sp., male; C. atacama n. sp., male; C. gauldi n. sp., male; C. incognita n.sp., female; and C. snellingi n. sp., male. Chilemutilla aptera is the first wingless mutillid male described from South America. In addition, we have prepared the first generic key for nocturnal sphaeropthalmine males from South America.

A new species, Stilobezzia (Acanthohelea) curvistyla from Argentinean and Chilean Patagonia is described and illustrated, and compared with the similar species S. (A.) nigerrima Ingram and Macfie. The latter species is redescribed, including the first description of the male, and for the first time recorded from Chile.

Argia yungensis sp. nov., a new species close to Argia difficilis, is described. Both species are illustrated and diagnosed and their distributions mapped. They can be distinguished by the morphology of male tori, cerci and paraproct, and female prothorax. Their distributions are allopatric, with Argia yungensis distributed along the foothill jungle of the Yungas rain forest from NW Argentina to Peru, and A. difficilis from Peru and Brazil to Venezuela across the lowland Amazon forest. Argia extranea forficula Fraser is synonymyzed with A. difficilis, and the latter is redescribed.