title: Revisiting the phylogeny ofWolbachiain Collembola.
abstract: The endosymbiontWolbachiahas been detected in a few parthenogenetic collembolans sampled in Europe and America, including three species of Poduromorpha, two species of Entomobryomorpha, and two species of Neelipleona. Based on 16S rRNA andftsZgene sequences, most of theWolbachiainfecting parthenogenetic collembolans were characterized as members of supergroup E and showed concordant phylogeny with their hosts. However, the two neelipleonan symbionts form another unique group, indicating thatWolbachiahas infected parthenogenetic collembolans multiple times. In this study, five parthenogenetic collembolan species were identified as hosts ofWolbachia, and four newWolbachiastrains were reported for four collembolan species sampled in China, respectively, including a neelipleonan strain fromMegalothorax incertus(wMinc). Our results demonstrated that theWolbachiamultilocus sequence typing (MLST) system is superior to the 16S rRNA +ftsZapproach for phylogenetic analyses of collembolanWolbachia. The MLST system assigned theseWolbachiaof parthenogenetic collembolans to supergroup E as a unique clade, which includedwMinc, supporting the monophyletic origin ofWolbachiain parthenogenetic collembolan species. Moreover, our data suggested supergroup E as one of the most divergent lineages inWolbachiaand revealed the discrepancy between the phylogenies ofWolbachiafrom parthenogenetic collembolans and their hosts, which may result from the high level of genetic divergence between collembolanWolbachia, in association with the geographic differentiation of their hosts, or the possible horizontal transmission ofWolbachiabetween different collembolan species.
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China; University of Chinese Academy of Sciences Beijing China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China.
authors.forename: Wan-Jun
authors.initials: WJ
authors.lastname: Chen
authors.affiliation: Institute of Applied Ecology Nanjing Xiaozhuang University Nanjing China.
authors.forename: Zhao-Hui
authors.initials: ZH
authors.lastname: Li
authors.affiliation: Department of Entomology College of Plant Protection Nanjing Agriculture University Nanjing China.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China.
authors.forename: Yun-Xia
authors.identifier: 0000-0003-3573-7144
authors.initials: YX
authors.lastname: Luan
keywords: Collembola; Wolbachia; genetic divergence; monophyletic origin; multilocus sequence typing; supergroup E