A Dwarf Euomphalid Fauna from the Permian-Triassic Boundary in Laolongdong, Beibei, Chongqing: Opportunity Taxa Surviving the Disaster Event?

• 责任者：Jiang Hongxia (Key Laboratory of Petroleum Geophysics ; Institute of Geology and Geophysics ; Chinese Academy of Sciences ; Beijing 100029 ; China) ; Wu Yasheng
• 刊名：Acta Geoscientica Sinica
• 出版年：2010
• 卷期：31(2)
• 关键词：扁卷螺属 ; Planorbis ; 重庆 ; Chongqing
• 页码：p.163-169
• 图表：3 illus., 38 refs.,
• 分类号：1103
• issnNo：ISSN1006-3021
• isbnNo：CN11-3474/P

This paper has reported  a euomphalid microgastropod fauna from the Permian-Triassic boundary section at Laolongdong, Chongqing. The euomphalids are characterized by planispiral or trochiform shell, obvious umbilicus, and calcite composition of the shell. The euomphalid fauna flourished for a short period after the mass extinction, and its blooming might have been related to the resuming of aerobic environments after an anoxic period. However, in the following time, the abundance of euomphalids kept low and failed to play an important role in the recovery of gastropods in the Early Triassic.