Like Botryllus, Botrylloides are flat sheets of organisms which can be found covering ropes, boat hulls, horseshoe crabs, seaweeds, and any still or slow-moving object in saltwater. Also both are considered to be invasive Ascidians, found in many ports around the world. Invasive tunicates such as these, Didemnum sp., and Styela clava are a problem for shellfish and other marine life populations, and cause fouling of boats and piers.
Species within the genus Botrylloides include:
Botrylloides anceps (Herdman, 1891)
Botrylloides aureum (Sars, 1851)
Botrylloides chevalense Herdman, 1906
Botrylloides diegensis Ritter & Forsyth, 1917
Botrylloides fuscus Saito & Watanabe, 1985
Botrylloides giganteum (PÈrËs, 1949)
Botrylloides israeliense Brunetti, 2009
Botrylloides leachii (Savigny, 1816)
Botrylloides lenis Saito & Watanabe, 1985
Botrylloides lentus Saito & Watanabe, 1985
Botrylloides magnicoecum (Hartmeyer, 1912)
Botrylloides nigrum Herdman, 1886
Botrylloides perspicuus (Herdman, 1886)
Botrylloides pizoni Brunetti & Mastrototaro, 2012
Botrylloides saccus Kott, 2003
Botrylloides simodensis Saito & Watanabe, 1981
Botrylloides superbum (Drasche, 1883)
Botrylloides tyreum Herdman, 1886
Botrylloides violaceus Oka, 1927
Species names currently considered to be synonyms:
