Ootheca

An ootheca /oʊ.əˈθiːkə/ (pl. oothecae /oʊ.əˈθiːsiː/) is a type of egg mass made by any member of a variety of species (usually insects or mollusks).

The word is a Latinized combination of oo-, meaning "egg", from the Greek word ōon (cf. Latin ovum), and theca, meaning a "cover" or "container", from the Greek theke. Ootheke is Greek for ovary.

An ootheca usually contains many eggs surrounded by a foam of protein which may then harden into a tough casing for protection. Notable ootheca-making insects are the mantis and cockroach.

It is formed by secretion of collateral glands, over 16 fertilised eggs are arranged in 2 rows of 8 each.They are found in genital pouch of female cockroach or mantis.

Female cockroach (Periplaneta fuliginosa) with ootheca

Female cockroach with ootheca

Sagittal section of mantis ootheca (Hierodula patellifera) already hatched out

Praying mantis (Mantis religiosa) Ootheca in Guelph, Ontario, Canada.

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