Ootheca
Image:Mantis egg 2005 Spring 001.jpg|thumb|Mantis ootheca
An ootheca is a type of egg capsule made by any member of a variety of animal groups such as mollusks, mantises, and cockroaches.
Etymology
The word is a Latinized combination of oo-, meaning "egg", from the Greek word ōon, and theca, meaning a "cover" or "container", from the Greek theke. Ootheke is Greek for ovary.
Structure
Oothecae are made up of structural proteins and tanning agents that cause the protein to harden around the eggs, providing protection and stability. The production of ootheca convergently evolved across numerous insect species due to a selection for protection from parasites and other forms of predation, as the complex structure of the shell casing provides an evolutionary reproductive advantage. Oothecae are most notably found in the orders Blattodea and Mantodea, as well as in the subfamilies Cassidinae and Korinninae.
Functions
The ootheca protects the eggs from microorganisms, parasitoids, predators, and exposure. Its composition and appearance vary depending on species and environment.