From hell's heart I stab at thee! A determined approach towards a monophyletic Pteromalidae and reclassification of Chalcidoidea (Hymenoptera) Author Burks, Roger https://orcid.org/0000-0003-3032-7939 Department of Entomology, University of California Riverside, Riverside, CA, USA burks.roger@gmail.com Author Mitroiu, Mircea-Dan https://orcid.org/0000-0003-1368-7721 Faculty of Biology, Alexandru Ioan Cuza University, Iasi, Romania Author Fusu, Lucian https://orcid.org/0000-0003-0819-026X Faculty of Biology, Alexandru Ioan Cuza University, Iasi, Romania Author Heraty, John M. https://orcid.org/0000-0002-9246-5651 Department of Entomology, University of California Riverside, Riverside, CA, USA Author Jansta, Petr https://orcid.org/0000-0001-6409-3603 Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic & Department of Entomology, State Museum of Natural History, Stuttgart, Germany Author Heydon, Steve Bohart Museum of Entomology, University of California, Davis, CA, 95616, USA Author Papilloud, Natalie Dale-Skey https://orcid.org/0000-0001-7582-0386 Insects Division, Natural History Museum, London, UK Author Peters, Ralph S. Zoologisches Forschungsmuseum Alexander Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany Author Tselikh, Ekaterina V. https://orcid.org/0000-0002-9184-043X Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia Author Woolley, James B. Department of Entomology, Texas A & M University, College Station, TX, USA Author van Noort, Simon https://orcid.org/0000-0001-6930-9741 Research and Exhibitions Department, South African Museum, Iziko Museums of South Africa, PO Box 61, Cape Town 8000 South Africa & Department of Biological Sciences, University of Cape Town, Private Bag, Rondebosch, 7701, South Africa Author Baur, Hannes https://orcid.org/0000-0003-1360-3487 Department of Invertebrates, Natural History Museum Bern, Bern, Switzerland & Institute of Ecology and Evolution, University of Bern, Bern, Switzerland Author Cruaud, Astrid https://orcid.org/0000-0001-8932-4199 CBGP, INRAE, CIRAD, IRD, Montpellier SupAgro, University of Montpellier, Montpellier, France Author Darling, Christopher Department of Natural History, Royal Ontario Museum, Toronto, ON, M 5 S 2 C 6, Canada & Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, M 5 S 1 A 1, Canada Author Haas, Michael https://orcid.org/0000-0001-6869-6698 Department of Entomology, State Museum of Natural History, Stuttgart, Germany Author Hanson, Paul Escuela de Biologia, Universidad de Costa Rica, San Pedro de Montes de Oca, San Jose 11501 - 2060, Costa Rica Author Krogmann, Lars https://orcid.org/0000-0002-3724-1735 Department of Entomology, State Museum of Natural History, Stuttgart, Germany & Institute of Biology, Biological Systematics (190 n) University of Hohenheim, Stuttgart, Germany Author Rasplus, Jean-Yves https://orcid.org/0000-0001-8614-6665 CBGP, INRAE, CIRAD, IRD, Montpellier SupAgro, University of Montpellier, Montpellier, France text Journal of Hymenoptera Research 2022 2022-12-20 94 13 88 http://dx.doi.org/10.3897/jhr.94.94263 journal article http://dx.doi.org/10.3897/jhr.94.94263 1314-2607-94-13 6CB807239A47403FABEC9AF8AE7F417F ADCFB8021287566FB2D7E8A8711D5CAE Heydeniidae new status, new placement Heydenini Hedqvist, 1961. Type genus: Heydenia Foerster , 1856. Spelling corrected to Heydeniini by Boucek (1988) . Diagnosis. Antenna with 10 or 11 flagellomeres, including 3 clavomeres. Eyes ventrally divergent. Clypeus without transverse subapical groove. Labrum exposed or hidden behind clypeus, sclerotized. Mandibles with 3 teeth. Pronotum expanded laterally and forming a subrectangular or laterally expanded structure from dorsal view (Fig. 67 ). Prepectus long, with large dorsal and ventral surfaces. Mesoscutellum either without a frenum, or with frenum laterally indicated by a frenal arm, with or without axillular sulcus (Fig. 68 ). Mesopleural area with acropleuron slightly expanded but occupying less than half its surface; mesepimeron not extending over anterior margin of metapleuron. All legs with 5 tarsomeres; profemur strongly (Fig. 69 ) or only mildly expanded; protibial spur stout and curved; basitarsal comb longitudinal. Metasoma with syntergum, therefore without epipygium, although terga not well-sclerotized and often difficult to assess. Discussion. Some species of Heydeniidae are distinctive and resemble Ooderidae , while more generalized species are considerably more difficult to recognize. Ooderidae differ in having multiple rows of spine-like structures on the ventral surface of the always strongly expanded profemur. Heydeniidae have instead at most a single row of crest-like structures ventrally on the profemur. Otherwise, the ventrally elongate prepectus of Heydeniidae is distinctive. When the profemur is not strongly expanded and the pronotum is relatively short and not tent-like, species of Heydenia Foerster can be more difficult to recognize. Given the presence of a convex mesoscutellum with a weakly distinct or indistinct frenum and ventrally divergent eyes, generalized Heydeniidae may be confused with Cleonymidae or Lyciscidae , both of which have a much shorter prepectus ventrally.