Canadian Hymedesmia Sponge

Authority

Ginn, Logan, Thomas & Van Soest, 1998

Classification Details

Phylum: Porifera (sponges); Class: Demospongiae (siliceous sponges).

Habitat

Found encrusting bedrock from depths of around 10 metres down to 40 metres. Scientifically described in 1998 and, until recently, known only from the waters around Deer Island in the Bay of Fundy. It has now also been recorded from Brier Island, Nova Scotia.

Diet

Sponges feed on small particles in the seawater. 80% of their diet is bacteria-sized particles (<0.5 micrometres in diameter). They suck seawater into a network of canals in their body using a current generated by cells called choanocytes. The choanocytes also capture the food particles.

Reproduction

Hermaphrodites – individuals are both male and female. Individuals release sperm into the water column. It is then sucked up by another sponge and used to fertilize its eggs. The sponge then broods embryos in its body tissue until they develop into free-swimming larvae that are released into the seawater. After a few days in the seawater, they settle and develop into adult sponges.

Fun Facts

Brian Ginn, a former student at the University of New Brunswick, discovered this species new-to-science while doing his Masters research project in 1998. It was first found in Little L'Etete Passage, close to Deer Island.

References

Bowen S, Goodwin C, Kipling D, Picton B (2018) Sea squirts and sponges of Britain and Ireland. Plymouth: Wild Nature Press.

Ginn BK, Logan A, Thomas MLH, Van Soest RWM (1998) Hymedesmia canadensis (Porifera: Poecilosclerida), a new species among new geographical records from the Bay of Fundy, New Brunswick, Canada. Journal of the Marine Biological Association of the United Kingdom 78, 1093–1100.

Goodwin C (2017) Field guide to the sponges of the Bay of Fundy. Huntsman Marine Science Centre. Available from https://www.researchgate.net/publication/319433507_Field_Guide_to_Sponges_of_the_Bay_of_Fundy.