Microstructure and formation of protective coverings in some plant-parasitic microarthropods

1. 介壳虫。用扫描电子显微镜观察了一些蛛科昆虫的雄性和雌性试验，并参照其相应的分泌器官对其显微结构进行了比较。高放大试验主要由蜡丝组成，但在观察的物种之间结构不均匀。从一团蓬松的细丝到薄、紧和宽的覆盖物的进化趋势是公认的，并且在不同的科群中是平行的。高级类型的测试是通过昆虫的振荡或几乎旋转的运动来进行的，但在白蛉中，雄性测试没有显示出这种运动的痕迹。似乎在蛛科中，这种运动发生在进化过程的早期阶段。形成薄和厚测试的另一个因素是从肛门排出的粘性物质。这种物质能抵抗一些脂质溶剂。因此，在结构上和物质上，先进的水蛭试验都能有效地保护覆盖物。害螨。提出了一种制备叶螨科扫描电镜标本的新方法。通过使用该方法制备的材料可以不收缩。1989年5 ~ 6月，在九州和冲绳的常绿阔叶乔木和多年生禾本科中采集了大量的蜘蛛螨，共5属10余种。确定了他们的生活类型。对它们进行了扫描电镜制备，并对其微观结构进行了观察。在扫描电镜观察的基础上，新发现并描述了两个被混淆为裂叶螨（Schizotetranychus celarius, Banks）的物种。研究还发现，属于“织巢”生活型的一种蜘蛛螨的雄性在其巢内的行为是非常敌对的。冷冻系统扫描电镜观察表明，这是由于他们之间的同类相食。

1. Scale insects. The male and female tests of some species of the family Diaspididae were observed in a scanning electron microscope, and their microstructures were compared with reference to corresponding secretory organs. Highly magnified tests are mainly composed of wax filaments, but not uniform in structure among the species observed. An evolutionary trend of the test from a fluffy mass of filaments to a thin, tight and broad covering is recognized, and in parallel in different groups of the family. Advanced types of tests are made by oscillatory or nearly rotatory movements of the insects, but in the Diaspidini the male test shows no trace of such movements. It seems that in the Aspidiotinae the movement takes place at an early stage of the evolutionary course. Another factor in forming thin and thick tests is a glutinous substance discharged from the anus. This substance is resistant against some lipid solvents. Thus, the tests of advanced diaspidids are effective protecting coverings both in structure and in substance.2. Spider mites. A new method of preparing specimens of Tetranychidae for scanning electron microscopy (SEM) was developed. By the use of this method material can be prepared without shrinking. Material was collected mainly from broad-leaved evergreen trees and perennial grasses during May to June, 1989, in Kyusyu and Okinawa, and many spider mites including more than 10 species of 5 genera were found in the collection. Their life types were determined. They were prepared for SEM and their microstructures were observed. On the basis of SEM observations, two species which have been confused under the name Schizotetranychus celarius (Banks) are newly recognized and described. It has also been found that males of a spider mite species belonging to the "woven nest" life type are very antagonistic in behavior within their nests. Cryo-system SEM observations have demonstrated that this is due to cannibalism among them.