疑源类Ammonidium Lister 1970与相关种的厘定及其生物地层和古地理意义

许多可归为疑源类Ammonidium Lister 1970的种被前人划为Multiplicisphaeridium Staplin，1961、Baltisphaeridium Eisenack 1958 ex Eisenack 1959及其他相似属，在某种程度上缩小了其原有定义范围. 报道了采自新疆西准噶尔洪古勒楞组下段保存良好的Ammonidiumloriferum、A. sprucegrovense，通过相关文献引证对比，并结合剖面部分该属标本化石，对Ammonidium属征作了修订.根据新属征特点，将Caiacorymbifer Tappan and Loeblich, 1971，Gracilisphaeridium Eisenack and Cramer, 1973，Naevisphaeridium Wicander, 1974, Puteoscortum Wicander and Loeblich, 1977，Craterisphaeridium Deunff, 1981, Pertusisphaeridium Turner，1986和Martinsphaeridium Sarjeant and Vavrdová，1997等相似属纳入Ammonidium属的晚出异名.Ammonidium sprucegrovense var. polyankistrum Wicander and Loeblich, 1977由种级降为了变种级.建立1个新种:Ammonidium levigatum n. sp.，前人报道的部分标本被误归为A.loriferum或A. sprucegrovense.新种Ammonidium levigatum n. sp.在全球晚泥盆世古大陆边缘具有全球分布特征，是识别晚泥盆世疑源类的标准化石之一. 

Taxonomic Reconsideration of Ammonidium Lister 1970 and Related Species and Its Biostratigraphical and Palaeogeographical Implication

Many species that can be attributed to Ammonidium Lister, 1970 have been differently assigned to Multiplicisphaeridium Staplin, 1961, Baltisphaeridium Eisenack, 1958 ex Eisenack, 1959 and other similar genera, which, to some extent, narrowed the original definition. The diagnosis of Ammonidium is emended here in based on reference comparison and some Ammonidium taxa collected recently from the lower part of the Hongguleleng Formation, NW Xinjiang. This paper considers Caiacorymbifer Tappan and Loeblich 1971, Gracilisphaeridium Eisenack and Cramer 1973, Naevisphaeridium Wicander 1974, Puteoscortum Wicander and Loeblich 1977, Craterisphaeridium Deunff 1981, Pertusisphaeridium Turner 1986, and Martinsphaeridium Sarjeant and Vavrdová 1997 are junior synonyms of Ammonidium. The taxonomical ranks of Ammonidium sprucegrovense var. polyankistrum Wicander and Loeblich, 1977 are changed from the species to the varietas level. A new species is proposed, i.e., Ammonidium levigatum n. sp., which may have been erroneously identified as A.loriferum (Deunff) Hashemi and Playford 1998 or A. sprucegrovense(Staplin) Lister 1970 in many publications.Ammonidium levigatum n. sp. is widely distributed in the margins ofpalaeocontinents and is an important stratigraphical index fossil for the Late Devonian.