纠头甲螨属在中国的首次报道及一新种记述(蜱螨亚纲:甲螨亚目:耳头甲螨科)

记述纠头甲螨属一新种,命名为异毛纠头甲螨Eurostocepheusheterotrichussp.nov.,此外对该属的一些形态特征予以讨论。模式标本保存于白求恩医科大学生物教研室。     

中国元三甲螨科一新记录属及一新记录种(蜱螨亚纲:甲螨亚目:真卷甲螨总科)

记述中国元三甲螨科Oribotritiidae 1新记录属:原元三甲螨属Protoribotritia Jacot,1938及中国1新记录种:疏毛原元三甲螨Protoribotritia oligotricha Mirkel,1963,给出了形态描述和特征图.研究标本保存在中国科学院动物研究所国家动物博物馆.     

中国大翼甲螨科一新纪录属(蜱螨亚纲,甲螨亚目,大翼甲螨科)(英文)

记述了采自中国湖北的大翼甲螨科1新纪录属和1新纪录种:半大翼甲螨属Dimidiogalumna Engelbrecht,1972和东氏半大翼甲螨Dimidiogalumna azumai Aoki,1996,并制作了该属所有种的区别特征对照表。研究标本保存于贵州大学昆虫研究所。     

一种改进的小型节肢动物无形态损伤的DNA提取方法

本文介绍了一种改进的小型节肢动物无形态损伤的DNA提取方法,并在双尾纲、原尾纲和弹尾纲中进行了实验验证。结果表明,该方法可以高效的提取三类小型节肢动物的DNA,并用于扩增目标基因序列,凭证标本的回收质量高,有助于进一步的分类鉴定。该方法有望对螨、蚜虫、介壳虫、蚤等其他小型节肢动物的分子鉴定提供方便。     

FIRST RECORD OF THE GENUS DIMIDIOGALUMNA ENGELBRECHT (ACARI,ORIBATIDA, GALUMNIDAE) FROM CHINA

记述了采自中国湖北的大翼甲螨科1新纪录属和1新纪录种:半大翼甲螨属Dimidiogalumna Engelbrecht,1972和东氏半大翼甲螨Dimidiogalumna azumai Aoki,1996,并制作了该属所有种的区别特征对照表.研究标本保存于贵州大学昆虫研究所.     

保存方式和回软温度对蜜蜂标本DNA提取的影响北大核心CSCD

旨在探寻保存方式及制作干标本前回软温度对蜜蜂不同部位DNA的影响。采用酚-氯仿法对不同方式保存的蜜蜂以及不同温度回软后的蜜蜂干标本的总DNA进行提取,通过琼脂糖凝胶电泳和PCR扩增对DNA的提取结果进行鉴定。电泳结果显示,从新鲜标本、无水乙醇泡制或自然干燥保存半年的标本中均可提取到较高质量的总DNA,尤以头部与足部提取效果最佳。经不同水浴温度回软后保存半年的蜜蜂干标本总DNA提取结果显示,回软温度为65℃时对蜜蜂DNA的破坏性最小,DNA提取的最佳部位为蜜蜂足部。正交试验结果显示,55℃回软后的足部为蜜蜂干标本DNA提取的最优组合。PCR扩增结果显示,本实验提取的总DNA能成功地应用于蜜蜂线粒体基因16S rRNA和COI的扩增。从保存方式、提取部位和回软操作3个因素对蜜蜂标本DNA的提取进行了研究,提供了较好的选择方案。     

保存方式和回软温度对蜜蜂标本DNA提取的影响

旨在探寻保存方式及制作干标本前回软温度对蜜蜂不同部位DNA的影响。采用酚-氯仿法对不同方式保存的蜜蜂以及不同温度回软后的蜜蜂干标本的总DNA进行提取,通过琼脂糖凝胶电泳和PCR扩增对DNA的提取结果进行鉴定。电泳结果显示,从新鲜标本、无水乙醇泡制或自然干燥保存半年的标本中均可提取到较高质量的总DNA,尤以头部与足部提取效果最佳。经不同水浴温度回软后保存半年的蜜蜂干标本总DNA提取结果显示,回软温度为65℃时对蜜蜂DNA的破坏性最小,DNA提取的最佳部位为蜜蜂足部。正交试验结果显示,55℃回软后的足部为蜜蜂干标本DNA提取的最优组合。PCR扩增结果显示,本实验提取的总DNA能成功地应用于蜜蜂线粒体基因16S rRNA和COI的扩增。从保存方式、提取部位和回软操作3个因素对蜜蜂标本DNA的提取进行了研究,提供了较好的选择方案。     

中国元三甲螨属六新纪录种(甲螨亚目,元三甲螨科)

记述中国元三甲螨属6新纪录种:双元三甲螨Oribotritia anceps NiedbaΙa,2000、狭元三甲螨Oribotritia angusta Mahunka,1982、亚洲元三甲螨Oribotritia asiatica Hammer,1977、父岛元三甲螨Oribotritia chichijimensis Aoki,1980、大元三甲螨Oribotritia gigas Bayoumiet Mahunka,1979、尼泊尔元三甲螨Oribotritia nepalensis NiedbaΙa,2000,并给出了6新纪录种的特征图。研究标本除注明保存在波兰亚当密茨凯维奇大学动物分类与生态学系(DATE)外,其余均保存在中国科学院动物研究所国家动物博物馆。     

中国三甲螨科1新记录属及2新记录种

记述我国三甲螨科1新记录属：印三甲螨属Indotritia Jacot,1928及中国2新记录种：爪哇印三甲螨Indotritia javensis（Sellnick,1923）和波状印三甲螨Indotritia undulata Bayoumi ＆ Mahunka,1979,给出了形态描述和特征图。所有标本材料均保存在中国科学院动物研究所国家动物博物馆。     

中国卷甲螨科一新纪录属及三新纪录种(蜱螨亚纲,甲螨亚目,卷甲螨总科)

记述中国卷甲螨科Phthiracaridae1新纪录属,霍卷甲螨属HoplophthiracarusJacot,1933以及3新纪录种,坑霍卷甲螨H.foveolatusAoki,1980,伊利诺斯霍卷甲螨H.illinoisensis(Ewing,1909)和热带霍卷甲螨H.tropicusMondal et Kundu,1988,附详细描述及特征图。研究标本保存于中国科学院动物研究所国家动物博物馆。     

An efficient and non-destructive DNA extraction method for oribatid mites

Molecular methods play an important role in systematic acarology and DNA extraction is the first step in this ground. Nowadays, the varieties of methods are being used for extraction of DNA, but most of them destroy the important external characters that are essential for morphological identification. In order to overcome the problem of associating molecular and morphological information, we have developed a simple, efficient and non-destructive DNA extraction method for oribatid mites. The non-destructive method was tested on three different species [Oppia nitens C.L. Koch, 1836 (Oppiidae), Acrotritia ardua C.L. Koch, 1841 (Euphthiracaridae), and Amerus polonicus Kulczynski, 1902 (Ameridae)] and exoskeleton of specimens were preserved in Hoyer’s medium on glass microscopic slides for further identification via morphological studies. This method is more time consuming than commercial kits, but is easier and cheaper, meanwhile, allows systematic analysis with linking the morphological and genetic traits from a single mite. The most important advantage of TNES method is that after using this non-destructive method, specimens preserve all of their morphological features.     

Oribatid Mites as Potential Vectors for Soil Microfungi: Study of Mite-Associated Fungal Species

The ability of soil-living oribatid mites to disperse fungal propagules on their bodies was investigated. Classical plating methods were applied to cultivate these fungi and to study their morphology. Molecular markers were used for further determination. The nuclear ribosomal large subunit and the nuclear ribosomal internal transcribed spacer of DNA extracts of the cultured fungi as well as total DNA extracts of the mites themselves, also containing fungal DNA, were amplified and sequenced. Based on phylogenetic analysis, a total of 31 fungal species from major fungal groups were found to be associated with oribatid mites, indicating that mites do not selectively disperse specific species or species groups. The detected taxa were mainly saprobiontic, cosmopolitan (e.g., Alternaria tenuissima), but also parasitic fungi (Beauveria bassiana) for whose dispersal oribatid mites might play an important role. In contrast, no mycorrhizal fungi were detected in association with oribatid mites, indicating that their propagules are dispersed in a different way. In addition, fungi that are known to be a preferred food for oribatid mites such as the Dematiacea were not detected in high numbers. Results of this study point to the potential of oribatid mites to disperse fungal taxa in soil and indicate that co-evolutionary patterns between oribatid mites and their associated fungi might be rare or even missing in most cases, since we only detected ubiquitous taxa attached to the mites.     

Coupling non-destructive DNA extraction and voucher retrieval for small soft-bodied Arthropods in a high-throughput context: the example of Collembola

Here, we describe a simple method adapted for high-throughput protocols allowing voucher specimen recovery for Collembola and by extension for other soft-bodied small arthropods. A standard extraction protocol was tested to examine the effects of lysis duration (1, 2, 4, 12 h) on DNA concentration, amplification success and specimen condition. Good quality DNA was obtained after 1 h of lysis, while voucher condition was fine for up to 12 h. The lysis step substantially shortens the clearing process necessary for morphological examination.     

Nondestructive DNA extraction from blackflies (Diptera: Simuliidae): retaining voucher specimens for DNA barcoding projects

A nondestructive, chemical-free method is presented for the extraction of DNA from small insects. Blackflies were submerged in sterile, distilled water and sonicated for varying lengths of time to provide DNA which was assessed in terms of quantity, purity and amplification efficiency. A verified DNA barcode was produced from DNA extracted from blackfly larvae, pupae and adult specimens. A 60-second sonication period was found to release the highest quality and quantity of DNA although the amplification efficiency was found to be similar regardless of sonication time. Overall, a 66% amplification efficiency was observed. Examination of post-sonicated material confirmed retention of morphological characters. Sonication was found to be a reliable DNA extraction approach for barcoding, providing sufficient quality template for polymerase chain reaction amplification as well as retaining the voucher specimen for post-barcoding morphological evaluation.     

Community structure,trophic position and reproductive mode of soil and bark-living oribatid mites in an alpine grassland ecosystem

The community structure, stable isotope ratios (¹⁵N/¹⁴N, ¹³C/¹²C) and reproductive mode of oribatid mites (Acari, Oribatida) were investigated in four habitats (upper tree bark, lower tree bark, dry grassland soil, forest soil) at two sites in the Central Alps (Tyrol, Austria). We hypothesized that community structure and trophic position of oribatid mites of dry grassland soils and bark of trees are similar since these habitats have similar abiotic characteristics (open, dry) compared with forest soil. Further, we hypothesized that derived taxa of oribatid mites reproducing sexually dominate on the bark of trees since species in this habitat consume living resources such as lichens. In contrast to our hypothesis, the community structure of oribatid mites differed among grassland, forest and bark indicating the existence of niche differentiation in the respective oribatid mite species. In agreement with our hypothesis, sexually reproducing taxa of oribatid mites dominated on the bark of trees whereas parthenogenetic species were more frequent in soil. Several species of bark-living oribatid mites had stable isotope signatures that were similar to lichens indicating that they feed on lichens. However, nine species that frequently occurred on tree bark did not feed on lichens according to their stable isotope signatures. No oribatid mite species could be ascribed to moss feeding. We conclude that sexual reproduction served as preadaptation for oribatid mites allowing them to exploit new habitats and new resources on the bark of trees. Abiotic factors likely are of limited importance for bark-living oribatid mites since harsh abiotic conditions are assumed to favor parthenogenesis.     

Molecular phylogeny of oribatid mites (Oribatida, Acari): evidence for multiple radiations of parthenogenetic lineages

Nucleotide sequences of the D3 expansion segment and its flanking regions of the 28S rDNA gene were used to evaluate phylogenetic relationships among representative sexual and asexual oribatid mites (Oribatida, Acariformes). The aim of this study was to investigate the hypothesis that oribatid mites consist of species-rich clusters of asexual species that may have radiated while being parthenogenetic. Furthermore, the systematic position of the astigmate mites (Astigmata, Acariformes) which have been hypothesised to represent a paedomorphic lineage within the oribatid mites, is investigated. This is the first phylogenetic tree for oribatid mites s.l. (incl. Astigmata) based on nucleotide sequences. Intraspecific genetic variation in the D3 region was very low, confirming the hypothesis that this region is a good species marker. Results from neighbour joining (NJ) and maximum parsimony (MP) algorithms indicate that several species-rich parthenogenetic groups like Camisiidae, Nanhermanniidae and Malaconothridae are monophyletic, consistent with the hypothesis that some oribatid mite groups diversified despite being parthenogenetic. The MP and maximum likelihood (ML) method indicated that the D3 region is a good tool for elucidating the relationship of oribatid mite species on a small scale(genera, families) but is not reliable for large-scale taxonomy, because branches from the NJ algorithm collapsed in the MP and ML tree. In all trees calculated by different algorithms the Astigmata clustered within the oribatid mites, as proposed earlier.     

A DNA extraction procedure that allows mite specimens to be slide mounted: phytoseiid species evaluated as a model

Four protocols for extracting DNA from mites, using phytoseiid species as exemplars, were evaluated to determine whether the DNA obtained could be used to amplify nuclear, mitochondrial or Random Amplified Polymorphic DNA (RAPD) markers from males, females and eggs. Protocol 3 was identified as the best and this allowed High-fidelity PCR (Hf-PCR) and Hf-RAPD PCR to be used successfully; it left behind the intact body of adult mites so they could be slide mounted for morphological analyses, although the eggs had to be pricked in order to yield sufficient DNA for amplifications. Protocol 3 involved soaking intact specimens in a GuSCN buffer and using a silica matrix, which binds nucleic acids, to yield DNA for amplification. The DNA isolated could be stored up to a month, indicating that the quality was good. This DNA extraction protocol will allow researchers to collect mites, store them in 95% ethanol, and subsequently extract sufficient DNA from single adults or eggs to provide diagnostic PCR products from both nuclear and mitochondrial DNA, yet leave the bodies intact for morphological analyses.     

Convergent evolution of defense mechanisms in oribatid mites (Acari, Oribatida) shows no "ghosts of predation past"

Oribatid mites are diverse and abundant terrestrial soil arthropods that are involved in decomposition of organic matter and nutrient cycling. As indicated by fossils starting from the Devonian, they evolved varied mechanisms and structures for defense from predators. We investigated four of these defensive structures (ptychoid body, hologastry, mineralization and opisthonotal glands) and used ancestral character state reconstruction to determine whether they evolved convergently and how many times this may have happened. Phylogenetic trees based on 18S rDNA were constructed for 42 oribatid mite species and two outgroup taxa using likelihood and Bayesian algorithms. The results suggest that at least three of the four defensive structures evolved convergently several times; for opisthonotal glands convergent evolution remains equivocal. This high level of convergence indicates that predation has been an important factor throughout the evolution of oribatid mites, contributing to morphological diversity and potentially also to species richness, as there are indications that some taxa radiated after the evolution of defense structures. Despite the ancientness of oribatid mites, defense structures seems to have been rarely lost, suggesting that they still are functional and necessary to reduce predation, rather than being 'ghosts of predation past'.     

Expanding the ‘enemy-free space’ for oribatid mites: evidence for chemical defense of juvenile Archegozetes longisetosus against the rove beetle Stenus juno

Adult oribatid mites are thought to live functionally in ‘enemy-free space’ due to numerous morphological and chemical defensive strategies. Most juvenile oribatid mites, however, lack hardened cuticles and are thus thought to be under stronger predation pressure. On the other hand, the majority of oribatids have exocrine oil glands in all developmental stages, possibly rendering chemical defense the crucial survival strategy in juvenile Oribatida. We manipulated tritonymphs of the model oribatid mite Archegozetes longisetosus to completely discharge their oil glands and offered these chemically disarmed specimens to the polyphagous rove beetle Stenus juno. Disarmed specimens were easily consumed. By contrast, specimens with filled oil glands were significantly protected, being rejected by the beetles. This is the first direct evidence that oil gland secretions provide soft-bodied juvenile oribatids with chemical protection against large arthropod predators.     

The ecological distribution of reproductive mode in oribatid mites, as related to biological complexity

The high incidence of asexuality in oribatid mites presents an unusual opportunity for examining hypotheses for the maintenance of sex. There is a presumed range in age of asexual species: many oribatid species are phylogenetically clustered, occurring in speciose early-derivative families or genera without sexual species, while others are phylogenetically isolated from other asexual species, occurring in later derivative taxa with sexual congeners. We examined the distribution of oribatid mite reproductive mode in soil of corn fields, grassy and shrub fields, and forests in central New York State (three replicate plots of each type, with 25 samples per plot), to test three ecological predictions from current theory. (1) If overall biotic uncertainty, as generated by competitors and predators, mediates the ecological distribution of oribatid mites, then the proportion of asexual oribatid mites should be negatively correlated with biological diversity; we examine this prediction using literature data as well. (2) If Muller’s Ratchet (the stochastic loss of best genotypes, which is independent of environment), mediates the success of asexuality, then no ecological pattern should exist. (3) If general purpose genotypes are characteristic of asexual oribatid mites, their habitat distribution should be broader than that of sexual species. For each plot the level of asexuality was compared to indices of overall biotic diversity, as calculated from the pooled oribatid mite (competitors) and mesostigmatid mite (predator) communities. We found no negative correlation in this relationship in our own data or in the literature analysis of 290 faunal surveys from 50 literature sources, so we reject biotic uncertainty as an important determinant of reproductive mode distribution. When only data on phylogenetically clustered asexuals are considered, there is instead a positive correlation between asexuality and diversity that is not explained. Because of the latter pattern we tentatively reject Muller’s Ratchet as the primary factor maintaining reproductive mode in these mites, but cannot reject it for isolated asexual species. Niche breadth in sexual and asexual oribatid mites provides no support for widespread general purpose genotypes but broad patterns in the literature suggest that the idea needs further investigation. Possible complicating or unknown factors that are discussed include historical disturbance in the study area, the relationship between parasitism and general biotic diversity, and the level and source of genetic diversity in asexual oribatid mites.