Katja R. Richert-Pöggeler, Emmanuelle Muller, Neil E. Olszewski, Michael Tristem, Pierre-Yves Teycheney, Benham E Lockhart, Balázs Harrach, Hanu R. Pappu, Jens Mayer, Andrew D. W. Geering, Jan Kreuze, John M. Coffin, Robert J. Gifford, Jonathan P. Stoye, James E. Schoelz, Hung Fan, Mikhail M. Pooggin, Livia Stavolone, Susan Seal, Hélène Sanfaçon, Sead Sabanadzovic, Jens H. Kuhn, Carlos Llorens, Welkin E. Johnson, Eugene V. Koonin, Dirk Lindemann, Indranil Dasgupta, Mart Krupovic, Jonas Blomberg, Roger Hull, Biologie Moléculaire du Gène chez les Extrêmophiles (BMGE), Institut Pasteur [Paris], Uppsala University, Tufts University School of Medicine [Boston], University of Delhi, University of California [Irvine] (UCI), University of California, University of Queensland [Brisbane], University of Glasgow, Hungarian Academy of Sciences (MTA), John Innes Centre [Norwich], Boston College (BC), International Potato Center [Lima] (CIP), Consultative Group on International Agricultural Research [CGIAR] (CGIAR), Institute of Virology [Dresden], Technische Universität Dresden = Dresden University of Technology (TU Dresden), Universitat de València (UV), University of Minnesota [Twin Cities] (UMN), University of Minnesota System, Saarland University [Saarbrücken], Amélioration génétique et adaptation des plantes méditerranéennes et tropicales (UMR AGAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Washington State University (WSU), Biologie et Génétique des Interactions Plante-Parasite (UMR BGPI), Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Mississippi State University [Mississippi], Agriculture and Agri-Food [Ottawa] (AAFC), University of Missouri [Columbia] (Mizzou), University of Missouri System, University of Greenwich, International Institute of Tropical Agriculture, Imperial College London, National Institutes of Health [Bethesda] (NIH), This work was supported in part through Battelle Memorial Institute's prime contract with the U.S. National Institute of Allergy and Infectious Diseases (NIAID, contract no. HHSN272200700016I, J.H.K.). E.V.K. is supported by intramural funds from the U.S. Department of Health and Human Services (to the National Library of Medicine). S.S. acknowledges support from SRI Funds from Mississippi Agriculture and the Forestry Experiment Station of Mississippi State University. J.F.K. is supported by the CGIAR Research Program on Roots, Tubers and Bananas (RTB) and supported by CGIAR Fund Donors (http://www.cgiar.org/aboutus/our-funders/). M.K. is supported by l’Agence Nationale de la Recherche (France) project ENVIRA., M. Krupovic, B. Harrach, S. Sabanadzovic, H. Sanfaçon, and J. H. Kuhn were members of the 2014–2017 International Committee on Taxonomy of Viruses (ICTV) Executive Committee. J. Blomberg, J. M. Coffin, H. Fan, R. Gifford, W. Johnson, D. Lindemann, J. Mayer, J. P. Stoye, and M. Tristem were members of the 2014–2017 ICTV Retroviridae Study Group. I. Dasgupta, A. D. Geering, R. Hull, J. F. Kreuze, B. Lockhart, E. Muller, N. Olszewski, H. R. Pappu, M. Pooggin, K. R. Richert-Pöggeler, J. E. Schoelz, S. Seal, L. Stavolone, and P.-Y. Teycheney were members of the 2014–2017 ICTV Caulimoviridae Study Group. R. Hull is retired from the John Innes Centre, Norwich, Norfolk, United Kingdom, ANR-17-CE15-0005,ENVIRA,Remodelage de la membrane cytoplasmique par les virus enveloppés d'archées(2017), International Potato Center, Technische Universität Dresden (TUD), University of Minnesota [Twin Cities], Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro), Julius Kühn Institute (JKI), University of Missouri [Columbia], Institut Pasteur [Paris] (IP), University of California [Irvine] (UC Irvine), University of California (UC), Biotechnology and Biological Sciences Research Council (BBSRC), Agriculture and Agri-Food (AAFC), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)