Most living cyclostome bryozoans are thought to reproduce via polyembryony in which

  • sperm is taken up from the surrounding seawater and results in an internally fertilised embryo
  • clonal replication of this embryo results in several genetically identical individuals
  • the embryos are brooded in a gonozooid before being released as larvae

The larvae of cyclostome bryozoans are short-lived and settle within hours of being released. Nothing is known about the structure or behaviour of the larvae of Tennysonia stellata.