A Comparative Study On The Female Genitalia And Oothecae Of Blattodea

This thesis is a comparative study on the female genitalia and oothecae of Blattodea. The related research history on reproductive types, oothecae and female genitalia of Blattodea is reviewed briefly. Female genitalia and oothecae of cockroaches of different reproductive types are compared to make the regular pattern clear. It has been discovered that there is a corresponding relationship among the structures of female genitalia, morphology of oothecae and reproductive types by observation and comparative study. The value of female genitalia, form of oothecae and reproductive types is discussed in taxonomic and phylogenic study.This study is carried out based on specimens that are collected from field, cultivated in the laboratory, deposited in insect collection and borrowed from other universities. In this paper,32species of17genera belonging to9subfamilies are examined, of which23species are type oviparous A,2species type oviparous B,6species type ovoviviparous A and1species type viviparous A. The female genitalia of all species are described and photographed (one species is illustrated); the oothecae of10species of4subfamilies also are described and photographed.It has been found that cockroaches of different reproductive types have significant differences in the structures of female genitalia and morphology of oothecae (differences between female genitalia of ovoviviparous A and viviparous A species are not significant). Differences of oothecae mainly contain that oothecae of type oviparous A are dark and hard with distinct keel, on which slits or openings are scattered; oothecae of type oviparous B are pale and slightly soft, with unconspicuous keel which only has openings; oothecae of type ovoviviparous A are pale and soft, without keel and usually not completely enclose eggs. Distinctions of female genitalia are mainly in the following areas:paraprocts of oviparous A cockroaches developed, the gap between two paraprocts very narrow and laterosternite IX developed; oviparous B cockroaches with auxiliary vavule which encloses the second and third valvules partly, paratergites developed, first valvifer arms developed and extending forward; ovoviviparous A cockroaches with paratergites elongate, dorsal extension of the first valvifer well-developed which lying adjacent to the base of paratergites and attaching to paratergites with membrane, first valvifer arms highly sclerited and extending forward to support brood sac, and laterosternite IX rudimentary; female genitalia of viviparous A cockroaches are most lightly sclerotized, first valvifer arms are fused, quadrate and extending forward. Research shows that there is a corresponding relationship among structures of female genitalia, morphology of oothecae and reproductive types; if features of female genitalia are known, it is able to infer the form of oothecae and reproductive types; that is to say, any one of the three is clear, it is possible to make the other two certain.The anatomical specimens are deposited in the College of Plant Protection, Southwest University (SWU).