A new gleicheniaceous fern Chansitheca (Sphenopteris) wudaensis from the Lower Permian of Wuda, Nei Mongol, China

作者：Deng SH^*; Sun KQ; Li CS

来源：Acta Botanica Sinica, 2000, 42(5): 533-538.

• Lower Permian
• Gleicheniaceae
• Chansitheca

Chansitheca (Sphenopteris) wudaensis sp. nov. is described based on the materials collected from the Lower Permian Shansi Formation of Wuda, Nei Mongol, China. The frond is small and at least two times pinnate. The pinnule is sphenopteroid. The sori are borne on the abaxial surface of the pinnule, arranged in two rows parallel to the midvein, elliptic, and composed of 4 - 10 round sporangia. The indusium is absent. The annulus is transverse and complete, and consists of about 18 thickened cells. The features of the fertile parts, sori, sporangia and annulus and the absence of indusium indicate that the new species belongs to the Gleicheniaceae.

• 出版日期2000-5
• 单位中国地质大学（北京）; 中国石油天然气股份有限公司勘探开发研究院