The female reproductive system of cockroaches consists of a pair of ovaries, oviduct, vagina, spermatheca, collaterial glands, genital pouch and external genitalia.
i. Ovaries: The female reproductive system includes a pair of ovaries present in between the 2nd to 6th segments of the abdomen. Each ovary is formed by a group of ovarian tubules that contains rows of ova in various stages of development.
ii. Oviduct and Vagina: The ovary continues down in the form of a short, muscular tube called an oviduct. The right and left oviduct units form a single median oviduct, also called the vagina, which opens into the genital chamber.
iii. Spermatheca: A pair of spermatheca present in the 6th segment opens into the genital chamber, and it is used for storing the sperm. The left spermatheca is large and functional, while the right spermatheca is reduced and non-functional.
iv. Genital Pouch or Chamber: The genital pouch is a sizable boat-shaped structure surrounded by three pairs of chitinous plates that help in copulation, deposition of the egg. It is formed by the 7th,8th and 9th abdominal segments. It is divided into two chambers. The smaller chamber is called the genital atrium and is opening for the collaterial gland, spermatheca and opening of the common oviduct. Its large posterior part is called the vestibulum.
v. Collaterial Gland: Collaterial glands are present on either side of a genital chamber into which they open. Collaterial glands help in the formation of egg cases or ootheca. The ootheca is a dark reddish to the blackish-brown capsule, about 8mm long. They are dropped or glued to a suitable surface, usually in a crack or crevice producing 9 to 10 ootheca, each containing 14 to 16 eggs.
vi. External Genitalia: The gonapophyses contains three chitinous plates.
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