Table 6 in The Lyckholm acme of cephalopods - Review of the late Katian (Vormsi-Pirgu regional stages) Ordovician cephalopods of Estonia
Table 6. Species turnover between Vormsi and Pirgu regional stages per cephalopod order. Note the high turnover (70 of 86 species change between the two stages).Orderdisappearances Vormsiappearances Pirgurange throughActinocerida132Ascocerida011Discosorida1472Endocerida101Oncocerida6201Orthocerida411Pseudorthocerida615Tarphycerida103basal Multiceratoidea130Total343616