• 责任者：Wang Xin (Xi’an Center of Geological Survey ; China Geological Survey ; Xi’an 710054 ; China) ; Wang Jian
• 刊名：Chinese Journal of Geology
• 出版年：2013
• 卷期：48(4)
• 关键词：笔石纲 ; Graptolithina ; 个体发育 ; ontogeny ; 陕西 ; Shaanxi Province
• 页码：p.1295-1301
• 图表：2 illus., 17 refs.
• 分类号：1102
• issnNo：ISSN0563-5020
• isbnNo：CN11-1937/P

     Oktavites spiralis is one of the most important member in the graptolite biozone of the Telychian stage （ late Llandovery, Silurian）, and is of great significance in biostratigraphy studies. To achieve a much more precise description of this species,we studied the specimens of Oktavites spiralis in different developmental stages from Cyrtograptus lapworthi zone of Langao area and got a much more understanding of the development of its proximal end. At the same time,we draw a conclusion that the phylogeny and development of 0. spiralis could also be one key to accurately defining this genus.