Select the search type
  • Site
  • Web




Reteporella graeffei
(Kirchenpauer, 1869)

Bridget Bradshaw (2013)



Fact Sheet



Physical Description


Life History & Behaviour


Development & Settlement

Anatomy & Physiology

Colony structure

Zooid structure

Food capture & Digestive system

Circulatory & Excretory system

Nervous & Sensory system

Evolution & Systematics


Fossil record

Biogeographic Distribution

Conservation & Threats

Future research

References & Links


Bryozoans incurred a slough of investigations in the first half of the 20th century, during which most of their basic biology was described and our knowledge of their anatomy and physiology has changed minimally since then.  Most studies of bryozoans concern species living at high latitudes in and around the North Sea, the deep seas, and in the reefs of the Mediterranean.  Within these ecosystems, a select few species have been the focus of the studies and thus their ecology is well known.  The more recent addition of bryozoan studies pertaining to their function within Jamaican reef ecosystems has opened the floor to further investigations of there place in coral reef ecology.  Below are a few questions and ideas for small projects that could be useful to further describe the biology of R. graeffei:   

-Does R. graeffei selectively feed using tentacular flicking?  If so, is there a pattern or obvious preference for types or sizes of particles?  Are particles of certain sizes or material specifically rejected? 

-Do the dimensions of lophophores determine the consumed-particle profile of a single zooid?  Of a colony?  Of a species? If so, is competition avoided through lophophore-size differentiation between two co-occurring species of bryozoan?

-Does environmental condition—i.e., temperature, salinity, water speed, predator presence, density of conspecifics—influence zooid differentiation and/or growth pattern in R. graeffei

-What are R. graeffei’s natural predators?

-Is there a certain collection of species typically found in association with R. graeffei and if so, what type of relationships exist between them—i.e., mutualisms, symbioses, commensalisms? 

-What is the genetic relationship of colonies within a reef?  What are the dispersal patterns (both short and long range)? 

-What kind of self-fertilization blocks exist, if any?  How are they affected by abiotic and biotic factors?  How common is self-fertilization? 

-What type of larvae are released—lecithotrophic or planktotrophic?  What is the preferred settlement environment and what biotic and abiotic cues do the larvae respond most strongly to? 

-What is the pattern and extent of interconnectedness between zooids?  How quickly do nerve impulses, nutrients, or hormones travel throughout the colony? Is there a limit to the distance between zooids that a signal can travel within the colony, and if so what is it?

While these questions vary in simplicity and ease of testing, all represent holes in our understanding of this species.  By pursuing answers we may continue to untangle the complexities of coral reef communities.  

Photo: Bridget Bradshaw, Heron Island Reef, 2013.