Chrysidid wasps (Hymenoptera: Chrysididae) from Cretaceous Burmese amber: Phylogenetic affinities and classification Daercio A.A. Lucena a , Gabriel A.R. Melo b, * a Laborat orio de Biologia Comparada e Abelhas (LBCA), Departamento de Biologia, Faculdade de Filosofia, Ci^ encias e Letras de Ribeir~ ao Preto, Universidade de S~ ao Paulo, Avenida Bandeirantes, 3900, 14040-901, Ribeir~ ao Preto, S~ ao Paulo, Brazil b Universidade Federal do Parana, Departamento de Zoologia, Laboratorio de Biologia Comparada de Hymenoptera, Caixa Postal 19020, 81531-980, Curitiba, Paran a, Brazil article info Article history: Received 3 November 2017 Received in revised form 10 February 2018 Accepted in revised form 20 March 2018 Available online 22 March 2018 Keywords: Chrysidoidea Cladistics Comparative morphology Cuckoo wasps abstract Representatives of chrysidid wasps are described for the first time from inclusions in Late Cretaceous Burmese amber. Five new genera and new species are described and illustrated: yAuricleptes nebulosus gen. et sp. nov., yAzanichrum pilosum gen. et sp. nov., yBohartiura glabrata gen. et sp. nov., yBurmasega ammirabilis gen. et sp. nov., and yMiracorium tetrafoveolatum gen. et sp. nov. We coded 49 morphological characters for species representing the subfamilies Amiseginae, Loboscelidiinae, Cleptinae and Chrys- idinae. The cladistic analysis recovered the following relationships: Cleptinae þ (yAuricleptes þ (yBurmasega þ (yMiracorium þ ((Loboscelidiinae þ Amiseginae) þ ((yAzanichrum þyBohartiura) þ (yPalaeochrum Krombein þ (extant Chrysidinae)))))). In light of the cladistic results, we discuss the implications of characters for the interpretation of phylogenetic relationships within the family, and explore the main morphological changes occurred during the diversification of the chrysidid wasps. © 2018 Elsevier Ltd. All rights reserved. 1. Introduction The diversity of Cretaceous insects revealed by inclusions in Burmese amber has increased considerably in recent years (e.g. Ross et al., 2010; Grimaldi, 2016; Guo et al., 2017; Ross, 2017). Many of the described taxa have no counterparts in the extant fauna, with some of them exhibiting very unique morphologies (e.g. Engel et al., 2016; Perrichot et al., 2016; Barden et al., 2017; Rasnitsyn et al., 2017). In Hymenoptera, much of the diversity is represented by families with extant descendants, although 12 of the 37 recorded families constitute extinct lineages (compiled from Ross, 2017 , with modifications). Among the stinging Hymenoptera (Aculeata), 13 families have representatives in Burmese amber, with a single familydFormicidaedcontaining almost half of the described species (20 of 50 named species). In Chrysidoidea, the 12 described species belong to the families Bethylidae, Dryinidae, Embolemidae and Falsiformicidae (Burmomyrma is most likely a falsiformicid, and not a formicid as proposed originally by Dlussky (1996), and the two putative Scolebythidae described recently by Cockx and McKellar (2016) probably do not belong in this family; Melo, unpubl. data). Up to now, chrysidid wasps have not been reported from Bur- mese amber. Chrysididae are a diverse group mostly composed of parasitoid and cleptoparasitic wasps distributed worldwide. The clade is divided into four main groups: (1) the Cleptinae, which parasitize prepupal larvae of sawfly wasps; the clade composed of the pan-tropical (2) Amiseginae and (3) Loboscelidiinae, both containing parasitoids specialized on eggs of phasmatodean walking sticks; and (4) the colorful clade composed of the chrys- idine cuckoo wasps, which are specialized cleptoparasites attacking primarily other solitary aculeate hymenopterans (Kimsey and Bohart, 1991). The oldest fossils assigned to the family are dated from the Late Cretaceous amber of Canada (Canadian amber; Campanian) (Evans, 1969; McKellar and Engel, 2014), Siberia (Taimyr amber; late Cen- omanian and Santonian) (Evans, 1973; Krombein, 1986), and France (Charentese amber; late Cenomanian) (Cockx et al., 2016). Other taxa assumed to be closely related to the living groups are known from the Eocene amber deposits of the Baltic region (Brues, 1933; Krombein, 1986), Russia (Kaliningrad) (Bischoff, 1916), and Ukraine (Rovno) (Perkovsky and Rasnitsyn, 2013); and taxa from the early Miocene from the Dominican Republic (Engel, 2006). * Corresponding author. E-mail address: garmelo@ufpr.br (G.A.R. Melo). Contents lists available at ScienceDirect Cretaceous Research journal homepage: www.elsevier.com/locate/CretRes https://doi.org/10.1016/j.cretres.2018.03.018 0195-6671/© 2018 Elsevier Ltd. All rights reserved. Cretaceous Research 89 (2018) 279e291