The infective form of schistosoma, called a cercaria, secretes proteases upon detection of human skin lipids (McKerrow & Salter, 2002).    From Wordnik.com.  [OpenWetWare - Recent changes [en]] Reference

During the cercaria stage they develop both a tail which enables them to find a host and a digestive tract and suckers.    From Wordnik.com.  [Platyhelminthes] Reference

In an internal organ of the snail (equivalent to the liver and pancreas combined) the miracidium transforms into a cercaria (the infective larval stage) in about a month.    From Wordnik.com.  [Chapter 6] Reference

Systemic treatment and cooking of all food had cleaned up the infective cercaria and individual infections, and after six months of intensive search, quarantine, and investigation, Kennon was morally certain that the disease had been eradicated.    From Wordnik.com.  [The Lani People] Reference

In this stage it grows into a cercaria which possesses a single opening digestive tract, suckers and a tail, enabling it to leave the snail and seek out the secondary intermediate host, usually an arthropod or a fish, where it encysts, becoming a metacercaria.    From Wordnik.com.  [Platyhelminthes] Reference

As the cercaria penetrates the skin, it transforms into a migrating schistosomulum.    From Wordnik.com.  [Sun.Star Network Online - Your Source of Philippine Community News] Reference

Penetration of the human skin occurs after the cercaria (a stage in the life cycle of the parasite) have attached to and explored the skin.    From Wordnik.com.  [Sun.Star Network Online - Your Source of Philippine Community News] Reference