Halichondria bowerbanki is a species of sponge that lives on rocky surfaces in the shallow subtidal, with occasional intertidal specimens under overhanging rocks. The physical appearance and structure of the species is variable and it has tassel

Tassel

A tassel is a finishing feature in fabric decoration. It is a universal ornament that is seen in varying versions in many cultures around the globe.-Etymology:...

-like irregular

Irregular

Something that is irregular does not follow the expected pattern. The term is used in many different fields, with quite different meanings.-Canon Law:...

 branches. Colonies

Colony (biology)

In biology, a colony reference to several individual organisms of the same species living closely together, usually for mutual benefit, such as stronger defense or the ability to attack bigger prey. Some insects live only in colonies...

can be up to 25 centimeters high with branches reaching 12 centimeters high. The color of the species is beige to brown in the summer, and light grey/yellow in the winter.