Three new species of the diatom genus Hannaea Patrick (Bacillariophyta) from the Hengduan Mountains, China, with notes on Hannaea diversity in the region

Abstract

Three new species of Hannaea Patrick from the Hengduan Mountains in China are formally described herein, based on light and scanning electron microscope observations. Hannaea yalaensis sp. nov. has three continuous inflations along the ventral margin, resulting in an undulate outline compared to the outline of the most commonly reported Hannaea species. The valve of Hannaea hengduanensis sp. nov. is narrower, asymmetrical about the apical axis with capitate apices, dorsal and ventral sides almost parallel. On the ventral side of valve is an unornamented central area. The valve of Hannaea clavata sp. nov. is clavate. Valve margin is straight or slightly curved. The apices of the valve constrict sharply to form the capitate ends. In addition, we also briefly described other Hannaea from this region. Here, we document the morphologies of these new species and discuss the biogeographic distribution of the genus Hannaea in Asia.

Keywords:

• Hengduan Mountains
• diatom
• biogeography
• Fragilariaceae
• new species
• Hannaea

Acknowledgments

We would like to thank Dr. Yue Cao and Bingwei Xing for help in the field and with sample collection. We thank LetPub (www.letpub.com) for its linguistic assistance during the preparation of this manuscript. RJB initially served as associate editor, but because she subsequently shared original data and analyses for this paper we include her as an author. Two reviewers provided valuable feedback.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research was supported by the National Natural Science Foundation of China [grant number 31770222]; the National Basic Science and Technology Work [grant number 2013FY110400].