Edaphic mesostigmatid mites (Parasitiformes, Mesostigmata) in a region of the Pampa biome of the state of Rio Grande do Sul, Brazil

ABSTRACT: The diversity of edaphic mites in Brazilian natural environments is little known, especially in the Pampa biome, in southern region of Brazil. The objective of this study was to evaluate the diversity and abundance of edaphic fauna of mesostigmatid mites in a region of the Pampa biome of the state of Rio Grande do Sul. Soil samples were collected in the municipality of Aceguá, in 2012 and 2013. Mites were extracted using Berlese-Tullgren modified funnels. In total, 1900 mesostigmatid mites were collected, representing 44 species from 23 genera and 10 families. The most abundant families were Rhodacaridae, Ologamasidae and Laelapidae, with respectively 903, 578 and 214 specimens, corresponding respectively to 47.5, 30.4 and 11.3% of the Mesostigmata collected. Laelapidae was the most diverse family, being represented by 22 species. The remaining families were each represented by 1-5 species. Gaeolaelaps (Laelapidae) was the most diverse genus, with 14 species. Rhodacaridae was represented by a single species, Binodacarus aceguaensis Duarte, Castilho, Cunha & Moraes, representing 47.5% of the mesostigmatids. Ologamasidae was represented by four species, with Neogamasellevans sp. corresponding to the second most abundant species, representing 27.5% of the mesostigmatids. Further analysis of the data, in terms of mite identification to species level and the potential use of the mites collected for applied biological control are needed.

摘要：巴西自然环境中的土壤螨（edaphic mites）多样性鲜为人知，尤以巴西南部的潘帕斯生物群落（Pampa biome）为甚。本研究旨在评估南里奥格兰德州（Rio Grande do Sul）潘帕斯生物群落区域内中气门螨（mesostigmatid mites）土壤动物群的多样性与丰度。2012年与2013年，研究团队在阿塞瓜市采集土壤样本，采用改良型伯利斯-图尔格林漏斗（Berlese-Tullgren modified funnels）法提取螨类。本次研究共采集到1900头中气门螨，隶属于10科23属44个物种。物种丰度最高的三个优势科分别为罗甲螨科（Rhodacaridae）、寡节厉螨科（Ologamasidae）与厉螨科（Laelapidae），个体数依次为903、578与214头，分别占采集到的中气门螨总个体数的47.5%、30.4%与11.3%。厉螨科的物种多样性最高，涵盖22个物种，其余各科均仅含1至5个物种。革厉螨属（Gaeolaelaps）是物种最丰富的属，共计14个物种。罗甲螨科仅含1个物种：Binodacarus aceguaensis Duarte, Castilho, Cunha & Moraes，占中气门螨总个体数的47.5%。寡节厉螨科含4个物种，其中新革塞伊瓦螨属未定种（Neogamasellevans sp.）为第二优势物种，占中气门螨总个体数的27.5%。后续仍需开展螨类物种水平的精准鉴定研究，并评估本次采集的螨类在应用生物防治中的潜在价值。