Schizoporella unicornis

The Single-horn Bryozoan

Phylum Bryozoa
Class Gymnolaemata 
Order Cheilostomata
Suborder Ascophora 
Family Schizoporellidae
Genus Schizoporella
Species unicornis

Description: Encrusting, colonies can be over 100 mm wide; usually dingy orange (can be white to dull red); disc-like colonies can be several layers thick as new layers grow over old dead ones; zooids are squarish with a rounded aperture, an indentation at the rear and a single spine below the aperture; the surface is perforated with many pores.

Habitat: It can be found growing on any hard surface especially on mussel shells, barnacles, floating docks and pilings.

Natural History: This bryozoan can be found year round, and is believed to have been brought to the Puget Sound with the Japanese Oyster, Crassostrea gigas. It grows in colonies formed by hundreds of individual zooids. In the competition for space, the more aggressive species stolon becomes larger when needed depending upon the thickness and size of the colony being overtaken.