The genus Synergus Hartig (Hymenoptera: Cynipidae: Synergini) in the New World: a complete taxonomic revision with a key to species Author Lobato-Vila, Irene Author Pujade-Villar, Juli 0000-0001-7798-2717 jpujade@ub.edu text Zootaxa 2021 2021-01-12 4906 1 1 121 journal article 8839 10.11646/zootaxa.4906.1.1 308129a3-a99f-4012-bb41-d3220692c398 1175-5326 4434000 09383AAD-8E30-4E50-A533-C6DA4D00E33C Synergus citriformis ( Ashmead, 1885 ) Ceroptres citriformis Ashmead, 1885 . Trans. Am. Entomol. Soc. 12: 300. Type material: USNM. Synergus niger Fullaway, 1911 . Ann. Entomol. Soc. Am. 4: 369. Type material: CAS ( lectotype ), paralectotypes in CAS and USNM. Synonymized by Lobato-Vila et al. (2020b: 683) . Synergus citriformis : Weld (1922) . Proc. U. S. Nat. Mus. 61 (18): 26. Synergus elegans Nieves-Aldrey & Medianero, 2011 . Zootaxa 2774: 4. Type material: MNCN ( holotype ), paratypes in MNCN and MEUP. Synonymized by Lobato-Vila & Pujade-Villar (2017: 6) . Diagnosis . See Lobato-Vila et al . (2020c: 14) . Distribution . USA : Florida and California ( Ashmead 1885 ; Fullaway 1911 ; McCracken & Egbert 1922 ); Panama ( Nieves-Aldrey & Medianero 2011 ); and Mexico : Aguascalientes , Ciudad de México , Guanajuato , Hidalgo , México , Michoacán , Morelos , Oaxaca , Puebla , Tlaxcala , Veracruz , and Zacatecas ( Lobato-Vila & Pujade-Villar 2017 ; Lobato-Vila et al. 2020b , 2020c ). Biology . Synergus citriformis is considered a generalist species, even though it is mainly associated with galls of Amphibolips on oaks within the Lobatae section. Found also in association with woolly galls initiated by Andricus , Striatoandricus (arisen by Cuesta-Porta et al. (2020) to include some previously known species within Andricus ) and Cynips , and with other gall morphotypes (never tuberous galls) initiated by Andricus , Atrusca , Cynips , Disholcaspis , Dros , and Loxaulus on oaks of both Quercus and Lobatae sections ( Ashmead 1885 ; McCracken & Egbert 1922 ; Nieves-Aldrey & Medianero 2011 ; Lobato-Vila & Pujade-Villar 2017 ; Lobato-Vila et al. 2020b , 2020c ). Remarks . The type material of both Ceroptres citriformis and of one its synonyms, Synergus elegans , was examined and the species was treated by Lobato-Vila & Pujade-Villar (2017: 6) , as well as treated by Lobato-Vila & Pujade-Villar (2018: 437) and Lobato-Vila et al . (2020b: 683 , 2020c: 14 ). The type material of Synergus niger was examined, commented on, and illustrated by Lobato-Vila et al. (2020b: 683) .