Artiopoda - Agnostida - Agnostidae
Parent taxon: Condylopygoidea according to E. B. Naimark and T. V. Pegel 2017
See also Harrington and Leanza 1957, Henningsmoen 1952, Hong et al. 2003, Westrop et al. 1996 and Whittington et al. 1997
Sister taxa: Ammagnostidae, Clavagnostidae, Condylopygidae, Diplagnostidae, Doryagnostidae, Glaberagnostus, Glyptagnostus, Leiagnostus, Megagnostus, Metagnostidae, Phalacromidae, Phalagnostus, Phaldagnostus, Pseudagnostidae, Ptychagnostidae, Spinagnostidae, Valenagnostus
Subtaxa: Acmarhachis Agnostinae Agnostus Aistagnostus Barrandagnostus Biciragnostus Connagnostus Eurudagnostus Formosagnostus Gymnagnostus Hadragnostus Homagnostus Idolagnostus Ivshinagnostus Kormagnostella Kormagnostus Kymagnostus Lotagnostus Micragnostus Neoagnostus Oncagnostus Oxyagnostus Peronopsinae Ptychagnostinae Quadrahomagnostus Semagnostus Strictagnostus Trilobagnostus
Type: Agnostinae
Ecology: slow-moving epifaunal detritivore
Distribution:
• Arenig of Argentina (2 collections), Norway (1)
• Arenigian of France (1)
• Ordovician of Argentina (6), Australia (1), Canada (5: Alberta, Newfoundland and Labrador), Norway (1), the United Kingdom (4), United States (3: Montana, Nevada, Texas)
• Tremadoc of Argentina (4), Bolivia (7), Canada (7: Alberta, Northwest Territories), France (1), Mexico (26), the United Kingdom (1), United States (2: Texas, Vermont)
• Cressagian of the United Kingdom (3)
• Ibexian of Norway (3)
• Cambrian of Antarctica (1), Argentina (47), Australia (49), Canada (86: Alberta, British Columbia, Newfoundland and Labrador, Quebec, Yukon), China (125), France (1), Greenland (15), Iran (1), Kazakhstan (144), North Korea (1), Norway (36), Poland (3), the Russian Federation (22), South Korea (6), Sweden (5), Turkey (2), the United Kingdom (4), United States (139: Alabama, Alaska, Arkansas, California, Idaho/ Utah, Missouri, Nevada, Nevada and Utah, Oklahoma, Pennsylvania, South Dakota, Texas, Utah, Vermont, Virginia, Wyoming)
• Taoyuanian of China (43), the Russian Federation (14), South Korea (56)
• Solvan of the Czech Republic (1)
• Delamaran of United States (1: Idaho)
Total: 880 collections including 1526 occurrences