PHYLOGENETIC RECONSTRUCTION BETWEEN THE OLD AND NEW WORLD SPIROIDES INFERRED FROM PLASTID TRNL-F AND NRDNA ITS SEQUENCES

 

GULZAR KHAN^1,3, FA-QI ZHANG^1,2 , QING-BO GAO¹, PENG-CHENG FU^1,3, RUI XING^1,3, 

JIU-LI WANG^1,3, HAI-RUI LIU^1,3 AND SHI-LONG CHEN^1,4*

 

¹Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology,

Chinese Academy of Sciences, Xining 810001, PR China

²School of Life Sciences, Southwest University, Chongqing 400715, PR China

³University of Chinese Academy of Sciences, Beijing 100039, PR China

⁴Qinghai Province Key Laboratory of Crop Molecular Breeding, Xining 810001, PR China

^*Correspondence author’s.email: slchen@nwipb.cas.cn.

Email addresses: Gulzar Khan: gulzar.palynology@gmail.com

 

Abstract

 

Distribution of similar taxa between the East Asia (old world) and new worlds fascinated the Botanists and Bio-geographers since the Linnaean time. The current study represents phylogenetic investigation of 39 Spiraea L., species covering their entire distribution in the new world (America) to the old world (Tibet PR China). In this study we used both plastidial marker (trnL-F) and nuclear internal transcribed spacer (nrDNA ITS). Phylogeny among the species implemented in the program PAUP* while divergence time was calibrated in BEAST 1.7.5. The analysis revealed that all 39 species of the genus are monophyletic. The study further suggested that ancestors of Spiraea were in the new world but their center of diversification is in East Asia. The estimated divergence time showed that S. virginiana endemic to North America is the oldest species with divergence time 21.1 MY. The divergence time of Spiraea species with disjunct distribution in the new world, Europe and East Asia e.g., S. hypericifolia, S. chamaedryfolia, S. douglasii, S. salicifolia and S. latifolia ranged from 7.44-1.83 MY with most during Pliocene (within the last 5 MY). The results concluded that isolation of Spiraea species occurred during the severe eco-climatic fluctuations period throughout the late Tertiary and Quaternary.

 

Key words: Radiation, Disjunction, Vicariance, Dispersal, Migration, Phylogeny.