Cristatella mucedo is a freshwater invertebrate sometimes known as a ‘moss animal’.
Individuals called zooids possess tentacle crowns for feeding and collectively form long gelatinous colonies with a soft, transparent body wall.
To the naked eye undisturbed colonies are ‘fuzzy’ and caterpillar-like in appearance.
Colonies are loosely attached to a substrate that might be a root, rock or manmade structure, via their muscular ‘foot’.
They can ‘glide’ slowly and divide by fission.
© Allman 1956
According to the eminent Victorian naturalist George Allman ‘a more interesting and beautiful animal than….Cristatella mucedo can scarcely be imagined’ (Allman 1856).
Allman’s iconic image of a Cristatella mucedo colony draped over a stem appears in many textbooks.
Cristatella mucedo is the only known member of the genus Cristatella. Find out what analysis of the organism's DNA tells us about this species.
Cristatella mucedo is found mainly in slow moving waters in the northern hemisphere. It attaches to a variety of substrates from plants to plastics. Find out more about its habitat.
Cristatella mucedo colonies form by zooidal budding. Find out how this fascinating animal reproduces.
Cristatella mucedo colonies provide a home for numerous other species, but not all of them are welcome. Find out what happens when leeches, snails and midge larvae move in.
Find out the conservation status of this species.
Get reference material for Cristatella mucedo.
Scanning electron micrograph of statoblast (approximately 1mm in diameter).© P. Taylor & B. Okamura.
Degenerate Cristatella mucedo colonies filled with statoblasts.© B. Okamura
Cristatella mucedo colony.© B Okamura
Plate showing colonies and statoblasts of Cristatella mucedo from: Allman, G.J. 1856. A monograph of the Fresh-water Polyzoa, including all the known species, both British and foreign. The Ray Society 28: 1-119.© Allman
Statoblasts ensnared in feather.© P Taylor & B Okamura
Sacs of myxozoan parasite within Cristatella mucedo colony.© B Okamura
Merit Researcher in the Bryozoa Group, focusing on the ecology and evolution of bryozoans and their myxozoan parasites.
'My PhD training was in marine ecology, but moving to the University of Oxford meant the ocean was not close to hand. I soon discovered that there are many lakes and ponds in the vicinity that are inhabited by Cristatella mucedo. I became fascinated by the consequences of a life history that allows clonal lineages to persist for an indefinite period of time and the role of waterfowl in dispersal. Although I now work on several freshwater bryozoans, C. mucedo remains my favourite, largely because it is such a beautiful organism.'
Aufwuchs are communities of small animals and plants intimately associated with inanimate and living substrata in aquatic environments.
Statoblasts are asexually produced encapsulated buds of a freshwater bryozoan. Statoblasts are released as the colony disintegrates and develop into new organisms in spring.
Metapopulation are a group of spatially separated populations of the same species which interact at some level.
Oligotrophic environments are low in nutrients.
Eutrophic environments are rich in mineral and organic nutrients.