Xiao-Feng Xue

Effects of Wolbachia on mtDNA variation and evolution in natural populations of Tetranychus urticae Koch.

We investigated the effects of Wolbachia infection on mtDNA variation in spider mites by sequencing a portion of the mitochondrial cytochrome oxidase I (COI) gene from 198 individuals of known infection status. Four Wolbachia strains were described in the current study, namely wUrtOri1, wUrtOri2, wUrtOri3 and wUrtCon1. As predicted, the haplotype and nucleotide diversity were lower in infected individuals than in uninfected individuals. However, these mtDNA haplotype data are not entirely concordant with the surface protein of wolbachia (wsp) sequence data and both infected and uninfected individuals were found of the same haplotype. Although values of Tajimas D and Fu & Lis F were consistently less than zero for most infected groups, McDonald–Kreitman tests suggested that the patterns of variation were different from those expected under neutrality in only the uninfected group. Thus, the neutrality tests do not show a clear effect of Wolbachia infection on patterns of mtDNA variation and substitution in spider mites.

Homoplastic evolution and host association of Eriophyoidea (Acari, Prostigmata) conflict with the morphological-based taxonomic system.

The superfamily Eriophyoidea is exceptionally diverse and its members are highly host-specific. Currently, the taxonomy of this group is based on morphology only. However, phylogenetic relationships in this group could be incorrect if the diagnostic morphological characters are homoplastic. Therefore, the phylogeny of 112 representative taxa of Eriophyoidea from China was determined using 18S, 28S D2-5 and D9-10 rRNA. Phylogenetic relationships were inferred through Bayesian, maximum likelihood and maximum parsimony methods, and then a number of clades or major clades were defined according to robust phylogenetic topologies combined with morphological comparison. Tests of monophyly showed that two of three families of Eriophyoidea as well as one subfamily and four tribes were not monophyletic. Ancestral character state reconstruction (ACSR) showed that five diagnostic morphological characters evolved several times, confounding the current taxonomy. Additionally, reconstruction of the history of host plant colonization suggested host switching occurred in a limited range of host plants. The host association data made it possible to determine taxonomic relationships more accurately. These results show that by integrating morphological and molecular information and host plant choice, it is possible to obtain a more accurate taxonomy and a deeper phylogenetic understanding of Eriophyoidea.

Eriophyoid mites (Acari: Eriophyoidea) from Iran, with descriptions of three new species, one new record and a checklist

ABSTRACT Three new species and one new record of the eriophyoid mites from Iran are described and illustrated. They are Aceria chenopodia n. sp. on Chenopodium album L. (Chenopodiaceae), Aceria mashhadiensis n. sp. on Polygonum arviculare L. (Polygonaceae), Tetra ferdowsiensis n. sp. on Ulmus minor Mill. (Ulmaceae), and Aceria fraxinivora (Nalepa, 1909) on Fraxinus excelsior (Oleaceae). All the new species described herein are vagrants on the host plant. A checklist of eriophyoid mites from Iran was provided.

Eriophyoid mites on coniferous plants in China with descriptions of a new genus and five new species (Acari: Eriophyoidea)

Abstract A new genus, five new species, a new record and three new combinations are reported: Paraphetehaburus cephalotaxus n. gen. and n. sp. on Cephalotaxus fortunei Hook.f. (Cephalotaxaceae); Keiferella guanegouensis n. sp. on Picea asperata Mast.(Pinaceae); Proiectus tabulaeformis n. sp. on Pinus tabulaeformis Carr. (Pinaceae); Proiectus thunbergis n. sp. on Pinus thunbergii Pari. (Pinaceae); Phyllocoptruta platyclada n. sp. on Platycladus orientalis (L.) Franco (Cupressaceae); Platyphytoptus pineae Castagnoli, 1973, new record; Jutarus abietis (Kuang and Luo, 2005) n. comb.; Phyllocoptruta huangshanensis (Kuang, 1999)n. comb.; Phyllocoptes shenyangensis (Kuang and Luo, 2005) n. comb. All are vagrants on leaf surfaces; no apparent damage was found on host plants. A key and a tableto the Chinese species of eriophyoid mites on coniferous plants are provided.

Mitochondrial genome evolution and tRNA truncation in Acariformes mites: new evidence from eriophyoid mites

The subclass Acari (mites and ticks) comprises two super-orders: Acariformes and Parasitiformes. Most species of the Parasitiformes known retained the ancestral pattern of mitochondrial (mt) gene arrangement of arthropods, and their mt tRNAs have the typical cloverleaf structure. All of the species of the Acariformes known, however, have rearranged mt genomes and truncated mt tRNAs. We sequenced the mt genomes of two species of Eriophyoidea: Phyllocoptes taishanensis and Epitrimerus sabinae. The mt genomes of P. taishanensis and E. sabinae are 13,475 bp and 13,531 bp, respectively, are circular and contain the 37 genes typical of animals; most mt tRNAs are highly truncated in both mites. On the other hand, these two eriophyoid mites have the least rearranged mt genomes seen in the Acariformes. Comparison between eriophyoid mites and other Aacariformes mites showed that: 1) the most recent common ancestor of Acariformes mites retained the ancestral pattern of mt gene arrangement of arthropods with slight modifications; 2) truncation of tRNAs for cysteine, phenylalanine and histidine occurred once in the most recent common ancestor of Acariformes mites whereas truncation of other tRNAs occurred multiple times; and 3) the placement of eriophyoid mites in the order Trombidiformes needs to be reviewed.

Eriophyoid mites from Northeast China (Acari: Eriophyoidea).

We describe and illustrate herein one new genus and eighteen new eriophyoid mite species (Acari: Eriophyoidea) collected in northeast China. They are: Shevtchenkella huzhongiensis sp. nov. on Ulmus davidiana Planch. var. japonica (Sarg. ex Rehder) Nakai (Ulmaceae), Shevtchenkella jingboicus sp. nov. on Acer sp. (Aceraceae), Calepitrimerus flexuosus sp. nov. on Spiraea flexuosa Fisch. ex Cambess. (Rosaceae), Calepitrimerus maximowiczii sp. nov. on Crataegus maximowiczii Schneid. (Rosaceae), Calepitrimerus pilosus sp. nov. on Agrimonia pilosa Ledeb. (Rosaceae), Calepitrimerus yichunensis sp. nov. on Sorbaria sorbifolia (L.) A.Br. (Rosaceae), Cupacarus oxyphyllus sp. nov. on Euonymus oxyphyllus Miq. (Cel-astraceae), Epitrimerus sambucus sp. nov. on Sambucus williamsii Hance (Caprifoliaceae), Epitrimerus wuyingensis sp. nov. on Acer sp. (Aceraceae), Longisolenidionus amurensis gen. nov & sp. nov. on Tilia amurensis Rupr. (Tiliaceae), Phyllocoptes jiagedaqiensis sp. nov. on Cunninghamia sp. (Taxodiaceae), Aculops huzhongensis sp. nov. on Salix sp. (Sali-caceae), Aculus huzhongsalixus sp. nov. on Salix sp. (Salicaceae), Tetra angelica sp. nov. on Angelica sp. (Apiaceae), Tetra jiagedaqia sp. nov. on Lespedeza sp. (Fabaceae), Vittacus mandshurica sp. nov. on Corylus sieboldiana Blume var. mandshurica (Maxim.) C. K. Schneid. (Betulaceae), Vittacus cannabus sp. nov. on Cannabis sativa L. (Moraceae), and Peralox dentatis sp. nov. on Ulmus sp. (Ulmaceae). Two species formerly assigned to Rhyncaphytoptus, R. abiesis (Xue, Song & Hong, 2006) and R. fabris (Xue, Song & Hong, 2006) were reassigned to Nalepella, based on the presence of seta vi on the apical shield, and other characteristics of Nalepella. One species formerly assigned to Rhyncaphytoptus, R. fargesis (Xue, Song & Hong, 2006) was reassigned to Pentaporca, based on the presence of seta vi on the apical shield, opisthosoma with five ridges and other characteristics of Pentaporca. At the same time, four new eriophyoid mite records from China are provided, Acaphyllisa distasa (Keifer, 1961) rec. nov. on Betula costata Trautv. (Betulaceae), Shevtchenkella ulmi (Farkas, 1960) rec. nov. on Ulmus sp. (Ulmaceae), Calepitrimerus cariniferus Keifer, 1938, rec. nov. on Artemisia argyi H. Lev. & Vaniot (Asteraceae), Aculodes dubius (Nalepa, 1891) species complex, rec. nov. on Roegneria sp. (Poaceae). With this publication, the number of eriophyoid mite species in the region reaches 101. A list of these eriophyoid mites is provided.

Three eriophyoid mite species (Acari: Eriophyoidea: Eriophyidae) from Iran

Three mite species of the family Eriophyidae from Iran are described and illustrated. They are: Tegolophus marrubiumer sp. nov. on Marrubium vulgare L. (Lamiaceae); Phyllocoptes sp. cf. balasi Farkas, 1962 on Sanguisorba minor Scop. subsp. minor (Rosaceae) and Aceria fasciculifolis sp. nov. on Astragalus fasciculifolius Boiss. (Fabaceae). Both new species described herein are vagrants on their respective host plants.

Eriophyid Mites (Acari: Eriophyoidea) on Bamboo from China, with Descriptions of Three New Species from the Qinling Mountains

Abstract Three new species of eriophyid mites on bamboo from the Qinling Mountains, northwestern China, are described and illustrated: Tegolophus bashaniae sp. nov. on Bashania fargesii (E. G. Camus) Keng f. et Yi (Poaceae: Bambuseae); Tegolophus fargesiae sp. nov. on Fargesia qinlingensis Yi et J.X. Shao, and Tetraspinus vulgaris sp. nov. on Bambusa vulgaris Schrader ex Wendland. All species are vagrants on leaf surfaces, causing no apparent damage. A key to known eriophyid mites on bamboo from China is provided.

The phylogenetic position of eriophyoid mites (superfamily Eriophyoidea) in Acariformes inferred from the sequences of mitochondrial genomes and nuclear small subunit (18S) rRNA gene.

Eriophyoid mites (superfamily Eriophyoidea) comprise >4400 species worldwide. Despite over a century of study, the phylogenetic position of these mites within Acariformes is still poorly resolved. Currently, Eriophyoidea is placed in the order Trombidiformes. We inferred the high-level phylogeny of Acari with the mitochondrial (mt) genome sequences of 110 species including four eriophyoid species, and the nuclear small subunit (18S) rRNA gene sequences of 226 species including 25 eriophyoid species. Maximum likelihood (ML), Bayesian inference (BI) and Maximum parsimony (MP) methods were used to analyze the sequence data. Divergence times were estimated for major lineages of Acari using Bayesian approaches. Our analyses consistently recovered the monophyly of Eriophyoidea but rejected the monophyly of Trombidiformes. The eriophyoid mites were grouped with the sarcoptiform mites, or were the sister group of sarcoptiform mites+non-eriophyoid trombidiform mites, depending on data partition strategies. Eriophyoid mites diverged from other mites in the Devonian (384Mya, 95% HPD, 352-410Mya). The origin of eriophyoid mites was dated to the Permian (262Mya, 95% HPD 230-307Mya), mostly prior to the radiation of gymnosperms (Triassic-Jurassic) and angiosperms (early Cretaceous). We propose that the placement of Eriophyoidea in the order Trombidiformes under the current classification system should be reviewed.

Cytoplasmic incompatibility and fitness benefits in the two-spotted spider mite Tetranychus urticae (red form) doubly infected with Wolbachia and Cardinium

Abstract Maternally inherited Wolbachia and Cardinium are widely distributed among arthropods, and their presence usually causes modifications of the reproduction and fitness of the host. Although co-infections of Cardinium and Wolbachia in the same host is common, yet relatively little is known about the multiple infections on host or the individual effects of each symbiont. In this study, we investigated the effects of, and interaction between, Wolbachia and Cardinium in the doubly infected two-spotted spider mite Tetranychus urticae (red form) in China. The individual cytoplasmic incompatibility (CI) level, bacteria density, fecundity, and host longevity were examined. Our results indicate that Wolbachia induced a week level of CI, while Cardinium-infected and doubly infected males causes severe CI. Wolbachia and Cardinium could not modify the CI strength and rescue CI each other. Wolbachia inhibited the proliferation of Cardinium in double-infected mites. The infection with Cardinium alone enhanced the fecundity of infected females. Interestingly, we found survival benefit in Wolbachia-infected, Cardinium-infected and the doubly infected females. We discuss the results observed with respect to the spread of bacterial infection in natural populations.