根据唐山市丰润区左家坞镇半壁山寒武系炒米店组下部含海绿石灰岩夹竹叶状灰岩中采集的三叶虫标本, 对小山城子虫属的定义和时代进行了修订, 将后平壤虫Metapianaspis Qian, 1994, 扎浪滩虫Zhalangtania Zhou in Zhou et al., 1996与小山城子虫属合并; 对其时代和分类位置进行了讨论, 将小山城子虫属归于唇头虫科 Cheilocephalidae Shaw, 1956, 在华北寒武系苗岭统顶部新建了Liostracina simesi-Placosema convexa带, 对于华北浅水台地相区和华南深水斜坡相区地层对比具有重要意义。
Based on the new material collected from the medium bedded to thin-bedded glauconitic limestone in the lowermost part of the Chaumitien Formation, the diagnosis and occurrences of the genus Shanchengziella Lu and Qian, 1983 have been revised. Metapianaspis Qian, 1994 and Zhalangtania Zhou in Zhou et al., 1996 are considered as synonymous with Shanchengziella, which is grouped within the family Cheilocephalidae Shaw, 1956. The trilobite Liostracina simesi-Placosema convexa Zone has been established for the last occurrence of Miaolingian Series in North China Platform. It is very useful and significant for the stratigraphical correlation between North China Platform and South China Slope.