Abstract: Objective To observe dynamic of the morphologic structure and activity of Human Demodex in different stages.Methods The mites are collected by the squeezing method and cellophane tape method,and they are screened by computer with the Motic DM B5 software.Results The morphologic structure and activity of Human Demodex in different stages are checked and described.The development process of Demodex folliculorum and Demodex brevis is similar,the life cycle included egg,larva(three pairs of legs),nymph(four pairs of legs)and adult.During the stage of nymph,Demodex folliculorum has a molting stage,so the nymph stage is divided into protonymph and nymph.And protonymph is shorter than nymph,with blurry coxal follicle.Demodex folliculorum and Demodex brevis have different morphologic structure.The legs and gnathosoma of the mites can move in every stage(except eggs).When the temperature is higher(>20 ℃),the mites move actively,especially the adult.The opisthosoma of Demodex folliculorum and Demodex brevis have biggish difference.And the proctodeum of female Demodex folliculorum is firstly observed and screened under water microscopy.Conclusion The life cycle pattern of Demodex includes the egg,larva,protonymph,nymph,adult.The larva has three pairs of legs,and the nymph(including protonymph)has four pairs of legs.They have different morphologic structure in different stages,so it is easy to identify.The larva,nymph and adult have the ability of activity.The subspecies of Demodex folliculorum and Demodex brevis may exist.

摘要： 目的 比较两种人体蠕形螨的各期形态结构特征以及活动性。方法 采用挤压涂片法和透明胶纸粘贴法获取蠕形螨,在数码显微镜MoticDMB5软件系统下动态观察,然后进行拍摄和测量。结果 对两种人体蠕形螨发育过程各个时期的形态特征和活动性进行了动态展示和描述。对比观察发现两种人体蠕形螨发育过程基本相似,均有卵、幼虫(3对足)、若虫(4对足)和成虫4期。由于毛囊蠕形螨若虫期有一次蜕皮,将其又分为前若虫和(后)若虫两期,前若虫较(后)若虫短,基节骨突不清。两种蠕形螨各期形态差异均较大,其活动性除虫卵外,各期均可见足和颚体活动,室温较高时(20℃以上)虫体运动活跃,移动明显。两种蠕形螨成虫末体变异也较大。另外,首次在水镜下拍摄到毛囊蠕形螨雌虫肛道(门)。结论 两种人体蠕形螨均分为卵、幼虫、若虫和成虫4期,各期形态结构差异明显,易于鉴别;幼虫、若虫和成虫均具有明显的活动能力。两种人体蠕形螨似有亚种存在。

关键词: 毛囊蠕形螨, 皮脂蠕形螨, 形态特征, 活动性