Occurrence ofCodium fragilesubspeciestomentosoidesin New Zealand waters

Abstract

Codium fragile (Sur.) Hariot subsp. tomentosoides (Van Goor) Silva is reported from Auckland Harbour. Although macroscopically similar to native forms of C. fragile, the subspecies can be positively identified by utricle anatomy. Its vigorous growth and efficient dispersal by asexual reproduction, and possibly by vegetative fragments, have resulted in a rapid spread to adjacent localities. These features suggest that the plant could be a nuisance to the shellfish industry as it has been in North America. The manner in which this weed was introduced is not clear, but transportation as a fouling organism, on ships is most probable.