Colony of Crystal Moss Animals Lophopus crystallinus
© micrographia.com
Crystal Moss Animal (or Bellflower) Lophopus crystallinus is a Red Listed freshwater bryozoan and the only member of the family Lophopodidae to be found in the UK. It is a very rare and tiny pond, ditch or slow flowing river dwelling creature that lives in colonies usually attached to water plants or substrates such as dead wood or leaves (rarely observed on hard substrates) just below the surface. Typically they measure 5-10 mm across and have a gelatinous coating. Out of water, a colony can look like snail or fish eggs, but in water the tentacled polyps are quite distinctive and very beautiful.
This species was once common and widespread but it has suffered a severe decline in the UK because of the loss of suitable habitat and is now only known from a handful of sites. It appears to prefer low water temperatures, being most often observed during the winter months, disappearing come the onset of spring. Observations suggest that they are predated by various worms, snails and caddis larvae. According to the Freshwater habitats Trust, although it lives happily in clean water, recent studies show it increases in abundance in nutrient-rich rivers so it may be a realtively easy species to protect, provided the correct habitat structure is in place.
There is a single record of the species in Sussex from 2004 where a colony of approximately 50 idividuals was observed in a stream that feeds into Burton Mill Pond. Please look out for these if you find yourself in or near suitable habitat this winter and add any sightings to iRecord but it would also be much appreciated if you were to let us know here at SxBRC to, please email bobforeman@sussexwt.org.uk including any photos.
Every month it is our aim to highlight a species that is “in-season” and, although not necessarily rare or difficult to identify, has been highlighted by our local recording groups as being somewhat under-recorded and for which new records would therefore be welcomed.
If you or your recording group are aware of species such as this then please contact Bob Foreman.