Description: Very small, uniserate filaments growing endozoically in hydroids. Branched filaments rising to less than 0.1 mm above the surface. The endozoic filaments branch and spread irregularly.

Habitat: Endozoic in hydroids in the lower littoral.

Distribution: Widely distributed in the British Isles. Europe: Mediterranean, Atlantic coast of France. Atlantic coast of North America: Maine to Connecticut and North Carolina. Further afield: the Canary Islands and California.

Similar Species: All species of Acrochaetium and Colaconema are very alike, microscopic examination is usually required for identification.

Distribution Map from NBN: Colaconema infestans at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Colaconema infestans at iNaturalist World Species Observations database.

WoRMS: Colaconema infestans at World Register of Marine Species. Accepted name: Colaconema infestans (M.Howe & Hoyt) Woelkerling, 1973. AphiaID: 502488.

Classification: Biota; Plantae; Biliphyta; Rhodophyta; Eurhodophytina; Florideophyceae; Nemaliophycidae; Colaconematales; Colaconemataceae; Colaconema