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Two new eriophyid mite species associated with Clematis terniflora var. mandshurica, namely Aculops jilinensis sp. n. and Phyllocoptes terniflores sp. n., are described. Both species infest the tender leaves of host plants, inducing severe curling and blistering. [ABSTRACT FROM AUTHOR]

Eriophyoid mites from Qinghai Province, northwestern China were studied herein. Up to now, only six species have been reported from Qinghai Province. In field surveys, 17 eriophyoid mite species were collected, among which nine species were found new to science. The new species and their host plants are listed as follows: Acaphyllisa tuberculumae sp. n. on Populus sp. (Salicaceae); Proiectus xiningensis sp. n. on Pinus sp. (Pinaceae); Phyllocoptes beishaniensis sp. n. on Spiraea mongolica Maxim. (Rosaceae); Tetra pruniana sp. n. on Prunus tomentosa Thunb. (Rosaceae) Rupr. (Berberidaceae); Tetra pyriana sp. n. on Pyrus calleryana Decne. (Rosaceae); Tetra simonia sp. n. on Populus simonii Carr. (Salicaceae); Diptacus berberinus sp. n. on Berberis amurensis Rupr. (Berberidaceae); Diptacus mengdaensis sp. n. on Lonicera elisae Franch. (Caprifoliaceae); Rhyncaphytoptus spinus sp. n. on Lonicera rupicola Hook. f. et Thoms. (Caprifoliaceae). Aculops ulmi Hong & Xue, 2005 was re-described. [ABSTRACT FROM AUTHOR]

The western flower thrips, Frankliniella occidentalis (Pergande), is an invasive species and the most economically important pest within the insect order Thysanoptera. F. occidentalis, which is endemic to North America, was initially detected in Kunming in southwestern China in 2000 and since then it has rapidly invaded several other localities in China where it has greatly damaged greenhouse vegetables and ornamental crops. Controlling this invasive pest in China requires an understanding of its genetic makeup and migration patterns. Using the mitochondrial COI gene and 10 microsatellites, eight of which were newly isolated and are highly polymorphic, we investigated the genetic structure and the routes of range expansion of 14 F. occidentalis populations in China. Both the mitochondrial and microsatellite data revealed that the genetic diversity of F. occidentalis of the Chinese populations is lower than that in its native range. Two previously reported cryptic species (or ecotypes) were found in the study. The divergence in the mitochondrial COI of two Chinese cryptic species (or ecotypes) was about 3.3% but they cannot be distinguished by nuclear markers. Hybridization might produce such substantial mitochondrial-nuclear discordance. Furthermore, we found low genetic differentiation (global FST = 0.043, P<0.001) among all the populations and strong evidence for gene flow, especially from the three southwestern populations (Baoshan, Dali and Kunming) to the other Chinese populations. The directional gene flow was further supported by the higher genetic diversity of these three southwestern populations. Thus, quarantine and management of F. occidentalis should focus on preventing it from spreading from the putative source populations to other parts of China. [ABSTRACT FROM AUTHOR]

The western flower thrips, Frankliniella occidentalis (Pergande), is an invasive species and the most economically important pest within the insect order Thysanoptera. For a better understanding of the genetic makeup and migration patterns of F. occidentalis throughout the world, we characterized 18 novel polymorphic EST-derived microsatellites. The mutational mechanism of these EST-SSRs was also investigated to facilitate the selection of appropriate combinations of markers for population genetic studies. Genetic diversity of these novel markers was assessed in 96 individuals from three populations in China (Harbin, Dali, and Guiyang). The results showed that all these 18 loci were highly polymorphic; the number of alleles ranged from 2 to 15, with an average of 5.50 alleles per locus. The observed (HO) and expected (HE) heterozygosities ranged from 0.072 to 0.707 and 0.089 to 0.851, respectively. Furthermore, only two locus/population combinations (WFT144 in Dali and WFT50 in Guiyang) significantly deviated from Hardy-Weinberg equilibrium (HWE). Pairwise FST analysis showed a low but significant differentiation (0.026 < FST < 0.032) among all three pairwise population comparisons. Sequence analysis of alleles per locus revealed a complex mutational pattern of these EST-SSRs. Thus, these EST-SSRs are useful markers but greater attention should be paid to the mutational characteristics of these microsatellites when they are used in population genetic studies. [ABSTRACT FROM AUTHOR]

Eriophyoid mites (Acari: Eriophyoidea) in Phyllocoptruta are reviewed. Two new species of Phyllocoptruta from Shaanxi Province, China, are described and illustrated: Phyllocoptruta huayangiana n. sp. on Rosa sericea Lindl. subsp, omeiensisi (Rolfe) A. V. Roberts (Rosaceae) and Phyllocoptruta clematoclethra n. sp. on Clematoclethra sp. Maxim. (Actinidiaceae). The new species described herein are vagrants on the undersurface of host leaves, causing no apparent injury. [ABSTRACT FROM AUTHOR]

Three new species of eriophyid mites on bamboo from the Qinling Mountains, northwestern China, are described and illustrated: Tegolophus bashaniae sp. nov. on Bashaniafargesii (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. [ABSTRACT FROM AUTHOR]

The Chinese population genetic structure of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), was investigated by amplifying and sequencing a portion (453 bp) in the mitochondrial DNA gene coding for cytochrome oxidase I (COI). The study was aimed at checking genetic difference among the Chinese populations of the mite and analyzing its possible dispersal within China. Thirteen populations from east, west, northeast, northwest, and central parts of mainland China were sampled. In the comparisons of these sequences, 36 nucleotide positions (7.9% of the total length) were found polymorphic, of which 88.9% were silent substitutions. Intraspecific variation analysis showed that the Xinjiang (XJ) sample differed from the other samples by an average of 4.68% nucleotide divergence, which was represented two different phylogenetic lineages in the phylogenetic tree. Apart from the XJ sample, the other samples displayed little variation (nucleotide divergences below 1.77%) with each other and clustered in one of the lineages. We argue that the reasons for the remarkable distinction are probably geographical barriers and the use of different host plants. [ABSTRACT FROM AUTHOR]