The taxonomy of the genus Chrysomphalus Ashmead (Diaspididae: Aspidiotinae) is reviewed. A new monotypic genus of armored scale, Pentalaminaspis Smith-Pardo, Evans and Dooley, is described and illustrated with Chrysomphalus minutus Kotinsky, 1908 as the type species. A new species, Chrysomphalus nepenthivorus Smith-Pardo, Evans & Dooley, is described and illustrated. This species was intercepted at a U.S. port of entry on hybrids of pitcher plants (Nepenthes) originating from Thailand. Chrysomphalus greeni Leonardi, 1914 is transferred to the genus Melanaspis and Chrysomphalus degeneratus Leonardi, 1896 is transferred to the genus Diaspidiotus. A discussion and key to species of the genus Chrysomphalus are provided as well as a key to aspidiotine genera similar to Chrysomphalus.

Cirrospilus floridensis, reared from the citrus leafminer, Phyllocnistis citrella Staintain, is described and illustrated. Zagrammosoma zebralineatum De Santis and Pnigalio flavipes (Ashmead) are synonymized with Zagrammosoma multilineatum (Ashmead) and Pnigalio minio (Walker), respectively.

Five parasite species, including two new species, Encarsia bellottii Evans and Castillo, n. sp. and Amitus macgowni Evans and Castillo, n. sp. were reared from Aleurotrachelus socialis Bondar on cassava, Manihot esculenta, in Colombia. E. bellottii was also reared from Trialeurodes variabilis (Quaintance) on cassava. The new species are described and illustrated.

Taxonomic, host, and geographic range information for the six species comprising the Encarsia cubensis species-group is provided. Three new species, E. aleurothrixi, E. hansoni, and E. hamoni are described from Brazil, Costa Rica, and Florida (USA), respectively. A lectotype is designated for E. nigricephala Dozier.

Four new host plant records and five new distribution records are reported for tenuipalpid mites collected in a survey of the phytophagous mites of Bermuda. A taxonomic key to the five tenuipalpid species and a host plant list are provided.

Encarsia polaszeki Evans n. sp., reared from the Bemisia tabaci complex from Brazil, is described and illustrated.

Four new species of Encarsia, E. lanceolata sp. n., E. paracitrella sp. n., E. pseudocitrella sp. n. and E. unicitrella sp. n. are described and illustrated. All four parasitoid species were reared from the Bemisia tabaci-complex and/or other whitefly hosts in the Neotropical region. Encarsia paracitrella, E. pseudocitrella and E. unicitrella are extremely closely related, to each other and to E. citrella (Howard). A diagnosis is therefore given for the E. citrella-complex, with a key to the four currently included species. For E. citrella (Howard) a lectotype is designated, the male is described and illustrated for the first time, and the female is redescribed and illustrated. A key and a modification to an existing key are provided to facilitate the identification of the five species treated.

A new species of the genus Eretmocerus, reared from Dialeurodes kirkaldyi (Kotinsky), is described and illustrated.

Four species of Encarsia, two of which are described as new, are assigned to the flavoscutellum species-group, which is diagnosed. Encarsia cerataphivora Evans, sp. nov. and Encarsia noordami Polaszek, sp, nov. are described from Cerataphis brasiliensis (Hempel) from Thailand, and from Astegopteryx nipae (van der Goot) from Malaysia, respectively. Encarsia flavoscutellum Zehntner and Encarsia thoracaphis (Ishii) are redescribed. A key is provided to separate these four species, and their distributions and host relationships are summarized.

A new species of an aphid parasitoid, Aphelinus spivaecolae Evans and Schauff (Hymenoptera: Aphelinidae) is described and figured. This species is parasitic on the spirea aphid, Aphis spiraecola Patch, and is being investigated for possible use in a biological control program against the spirea aphid and other citrus aphids including the brown citrus aphid, Toxoptera citricida (Kirkaldy). The new species is very similar to Aphelinus gossypii and characters to differentiate it from related species are given.

A key is provided for the recognition of previously described Encarsia species which are known to attack the tobacco whitefly, Bemisia tabaci (Gennadius). 28 nominal species are included, of which type material has been examined for 22. Eight new synonymies are proposed: Encarsia aleyrodis (Mercet) and F. partenopea Masi are both synonymized with E. inaron (Walker); E. bemisiae (Ishii) is synonymized with E. transvena (Timberlake); E. citri (Ishii) is synonymized with E. strenua (Silvestri), E. angelica Howard and E. deserti Rivnay & Gerling are both synonymized with E. luteola Howard; E. perspicuipennis (Girault) is synonymized with E. quaintancei (Howard); E. tabacivora Viggiani is synonymized with E. pergandiella Howard. E. hispida De Santis is removed from synonymy with E. meritoria Gahan. A lectotype is designated for E. porteri (Mercet). The known distributions and alternative hosts of Encarsia species attacking B. tabaci are provided as well as references to biology and notes on their use in biological control.