Escharella variolosa Johnston, 1838)


Escharella variolosa is an encrusting bryozoan. Colonies form bright, glistening sheets which are white or straw coloured. The sheets are composed of a single layer of autozooids and normally cover an extensive area. Autozooids are hexagonal or quadrate, often elongated, flat or slightly convex. They range in size from 0.6-0.8 by 0.3-0.5 mm, with two (rarely three) spines present. The zooids are arranged in regular, straight oblique rows.


Escharella variolosa is widespread throughout the NE Atlantic and western Mediterranean. It has been reported from the southern North Sea, the English Channel and the Scilly Isles, but is apparently rare or absent from the north-east coasts of the British Isles.


The species is able to colonise hard substrates. It occurs on other Bryozoa such as Cellaria sp and is often abundant on flat shells such as Ostrea, Chlamys and Pecten. It ranges from shallow inshore waters to at least 100 metres, but is thought to be absent from deeper waters.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith