• Abacaria Mosely, 1941
• Adranaria Munier-Chalmas, 1876 (uncertain)
• Ancaria Cameron, 1902 (uncertain)
• Aracari Temminck, 1820 (uncertain)
• Arancialia Hissmann, 2005
• Araucania Brundin, 1966 accepted as Reissmesa Ashe, 2000 [Family: Chironomidae]
• Araucania Chamberlin, 1956 accepted as Cesachile Koçak & Kemal, 2008 [Family: Geophilidae]
• Araucania Marsh, 1993 (accepted > junior homonym) [Family: Braconidae]
• Araucania Parodiz, 1954 accepted as Austrodiscus Parodiz, 1957 [Family: Charopidae]
• Araucania Pate, 1947 [Family: Sapygidae]
• Araucaria A.L. Jussieu, 1789
• Arcaria Rafinesque, 1815 accepted as Arca Linnaeus, 1758
• Arenaria Adanson, 1763 (unaccepted) [Family: Caryophyllaceae]
• Arenaria Bechstein, 1803 (uncertain) [Family: Aves (awaiting allocation)]
• Arenaria Brisson, 1760 [Family: Scolopacidae]
• Arenaria Chen & Shi, 2006 † accepted as Marginifera Waagen, 1884 † [Family: Thecidellinidae]
• Arenaria Linnaeus, 1753 [Family: Caryophyllaceae]
• Arenaria Megerle von Mühlfeld, 1811 accepted as Scrobicularia Schumacher, 1815 [Family: Myidae]
• Arenaria Opitz, 1997 [Family: Cleridae]
• Arenaria Renier, 1804 (unaccepted) [Family: Animalia (awaiting allocation)]
• Aroniaria V.M. Mezhenskyj, 2012