Abstract: Objective To investigate whether there is Blomia tropicalis breeding in the flour warehouse of food factory in a civil aviation airport， and， if there is， to observe the morphological structure of the mite. Methods The flour samples were collected from the flour warehouse of food factory in a civil aviation airport. The breeding mites were isolated from the samples by direct microscopy and made into specimens to observe with a light microscope. Results Female Blomia tropicalis was found in the collected flour samples. Under the microscope， the mite was nearly spherical， and it had no tergum and claw. Its apodemeⅠwas developed and connected in the midline. The reproductive hole was located between the foot Ⅲ and IV level and was covered with a pair of oblique genital folds. The foot Ⅲ and Ⅳ had no solenoids. The copulatory pouch was a long， slightly curved tube， extending from the end of the mite. Conclusions Blomia tropicalis has been found in the flour warehouse of a food factory in the civil aviation airport. The main distinguishing feature of this mite is that it has no tergum， its feet have no pectinate inferior tarsus scales or claw， the feetⅠgenu has only one solenidia， and feet Ⅲ and Ⅳ have no solenidias.

Key words: Blomia tropicalis； Morphological feature； Separation； Identification； Flour warehouse

摘要： 目的 调查某民航机场食品厂面粉库有无热带无爪螨孳生，观察热带无爪螨的形态结构特征。方法 采集该机场食品厂面粉库的面粉样本，用直接镜检法分离其中孳生的热带无爪螨，并制作玻片标本，于光学显微镜下观察鉴定。结果 于采集的面粉样本中发现了热带无爪螨雌成螨，镜下可见该螨近似球形，无背板，足无爪。表皮内突Ⅰ发达，于中线处相连。生殖孔位于足Ⅲ~Ⅳ水平，被一对斜生的生殖褶覆盖。足Ⅲ、Ⅳ无感棒。交配囊呈长而稍弯并逐渐变细的管状结构，伸出螨体末端。结论 某民航食品厂面粉库厂中发现了热带无爪螨，该螨主要鉴别特征为无背板，足无栉齿状亚跗鳞片和爪；足Ⅰ膝节仅有1根感棒，且足Ⅲ、Ⅳ无感棒。

关键词: 热带无爪螨；形态特征；分离；鉴定；面粉库