Ammagnostidae

Ammagnostidae is a family of trilobites in the suborder Agnostina, small, eyeless, isopygous trilobites with a thorax consisting of 2 segments only. Four genera have been assigned to it:


 * Ammagnostus Öpik, 1967
 * Ammagnostus psammius Öpik, 1967 (Type)
 * Ammagnostus bassus (Öpik, 1967)
 * Ammagnostus bella Guo & Luo, 1996
 * Ammagnostus beltensis (Lochman, 1944)
 * Ammagnostus cryptus
 * Ammagnostus cylindratus Guo & Luo, 1996
 * Ammagnostus duibianensis Lu & Lin, 1989
 * Ammagnostus histus
 * Ammagnostus hunanensis
 * Ammagnostus integriceps Öpik, 1967
 * Ammagnostus laiwuensis (Lorenz, 1906)
 * Ammagnostus mitis Öpik, 1967
 * Ammagnostus sinensis Peng, 1987
 * Ammagnostus wangcunensis Peng & Robison
 * Hadragnostus Öpik, 1967
 * Hadragnostus las Öpik, 1967 (Type)
 * Hadragnostus edax Fortey & Rushton, 1976
 * Hadragnostus helixensis Jago & Cooper, 2005
 * Hadragnostus modestus (Lochman, 1944)
 * Kormagnostus Resser, 1938
 * Kormagnostus simplex Resser, 1938 (Type)
 * Kormagnostus boltoni Westrop et al., 1996
 * Kormagnostus copelandi Westrop et al., 1996
 * Kormagnostus flati Pratt, 1992
 * Kormagnostus inventus Shergold, 1982
 * Kormagnostus minutus (Schrank, 1975)
 * Kormagnostus seclusus (Walcott, 1884)
 * Proagnostus Butts, 1926
 * Proagnostus bulbus Butts, 1926 (Type)
 * Proagnostus centerensis Resser, 1938
 * Proagnostus maryvillensis Resser

They lived during the late Cambrian period to the Ordovician period.