New Early Cambrian Maikhanellids (Mollusca) from Zhangjiagou Section, South Shaanxi, China

• 作者: ZHANG Ya'nan LIU Yunhuan SHAO Tiequan WANG Qi QIN Jiachen ZHANG Wei LIANG Tanxing
• 来源期刊: 地质学报（英文版）
• 年，卷（期）: 2022,（2）
• 所属期刊栏目: ORIGINAL ARTICLES
• 页码范围: 440-446
• 页数: 7页
• 语种: 英文

摘要

A new maikhanellid genus, Totornatus gen. nov., from the Lower Cambrian (Fortunian Stage) of Zhangjiagou section at Xixiang County, southern Shaanxi Province, South China, is based on a new taxon T. strigatus gen. et sp. nov. Although showing similar morphology with a cap-shaped shell and an oval aperture to other members of the family, the new species differs from previous maikhanellids in its smooth apex. The apical field consists of dense, small, round or oval granules, which gradually merge to bigger, elongated, scale-like protrusions toward the apertural margin. On this basis, we establish Totornatus strigatus, which shows a transverse groove in two-ninths of its shell. This result enriches the diversity of the earliest mollusks and maikhanellids.