Biodiv Sci ›› 2016, Vol. 24 ›› Issue (10): 1129-1134.DOI: 10.17520/biods.2016219

• Orginal Article • Previous Articles     Next Articles

Distributional patterns of the monolete and trilete ferns in China

Xueping Wei1,2, Xianchun Zhang1,*()   

  1. 1 State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093
    2 Graduate University of Chinese Academy of Sciences, Beijing 100049
  • Received:2016-08-09 Accepted:2016-10-08 Online:2016-10-20 Published:2016-11-10
  • Contact: Zhang Xianchun

Abstract:

Spores are important for fern classification and sexual reproduction and they usually have apertures; monolete (bilateral) and trilete (tetrahedral) are the two common types. All of the 2,281 native Chinese fern species (including subspecies and varieties) were included in our survey of monolete and trilete species ratios and their distribution patterns. Result revealed that (1) the number of monolete species was higher than the number of trilete, and there was a positive correlation between the ratio of monolete: trilete species (MTR) and latitude, and also between MTR and altitude. MTR was also shown to increase with decreases in temperature and rainfall. Monolete ferns were found to have larger distributional areas than trilete ones and to be more tolerant to a colder and drier climate. It is hypothesized that monolete ferns have a strong capacity to adapt to an extreme habitat; and that (2) neither monolete nor trilete spore are of single origin as parallel evolution might exist during the evolution of ferns. This study sheds new light on niche adaptation in ferns, as well as the evolution and diversification of ferns.

Key words: monolete spores, trilete spores, parallel evolution, niche adaptation