Finding Hidden Outliers to Promote the Consistency of Key Morphological Traits and Phylogeny in Dennstaedtiaceae

Jun-Jie Luo,Si-Si Chen,Yue-Hong Yan,Bing Liu,Ting Wang,Yu-Feng Gu,Hui Shang,Li Liu

doi:10.3390/taxonomy1030019

Abstract

With the development of open science and technological innovation, using sharing data and molecular biology techniques in the study of taxonomy and systematics have become a crucial component of plants, which undoubtedly helps us discover more hidden outliers or deal with difficult taxa. In this paper, we take Dennstaedtia smithii as an example, based on sharing molecular database, virtual herbarium and plant photo bank, to clarify the outliers that have been hidden in Dennstaedtia and find the key morphological traits with consistent of molecular systematics. In molecular phylogenetic analyses, we used rbcL, rps4, psbA-trnH and trnL-F sequences from 5 new and 49 shared data; the results showed that Dennstaedtia smithii is nested within Microlepia rather than Dennstaedtia. We further studied the morphological characters based on the phylogeny result and found that D. smithii is distinguished from other species of Dennstaedtia by spore ornamentation and the unconnected of grooves between rachis and pinna rachis. According to morphological and molecular phylogenetic studies, our results supported that D. smithii should be a new member of Microlepia and renamed Microlepia smithii (Hook.) Y.H. Yan. Finding hidden outliers can promote the consistency of morphological and molecular phylogenetic results, and make the systematic classification more natural.

Highlights

From the evolutionary emergence of primitive organisms to today’s broad variety of organisms, people have been constantly exploring how many species there are on the earth and what kind of evolutionary relationship among species
Using scanning electron microscopy (SEM) observation, we found that D. smithii resembled those of Microlepia rather than of Dennstaedtia based on the spore micro-morphological characteristics [8,9,12,18,19,20,21,22,23,24]
By comparing the costal grooves between rachis and pinna rachis of Microlepia and the other clade of Dennstaedtia, we found that the rachis of Microlepia were unconnected with the pinna rachis (Figure 2B)

Summary

Introduction

From the evolutionary emergence of primitive organisms to today’s broad variety of organisms, people have been constantly exploring how many species there are on the earth and what kind of evolutionary relationship among species. With the development of open science and technological innovation, methods of species identification range from using morphological characteristics to the integration of various methods (e.g., molecular biology, bioinformatics, bionomics) [1,2,3,4,5], which help us gain a more in-depth understanding of the evolutionary process between organisms and their accurate position in the tree of life. Engler 1883 had long been recognized as a member of Typhonium Schott 1829 according to the morphological characteristics, but the molecular phylogenetic evidence indicated that it should belong to the Sauromatum Schott 1832 and was renamed as Sauromatum giganteum (Engl.) Cusimano and Hetterscheid 2010 [1]. An ancient group, have similar examples, one of which is Athyrium niponicum (Mett.) Hance 1873. A. niponicum had been treated as a member of Athyrium Roth 1875, but was later confirmed to be within

Methods

Results

Conclusion