Pyramimonas sp. The Race Rocks Taxonomy


On the east side of the island is the largest pool with Pyramimonas.

Pyramimonas is a green micro-algae, that is a type of phytoplankton.

Phytoplankton refers to the autotrophic component of the plankton that drifts in the water column.


Samples taken from the green water in the upper tidepools


Here it is photographed at 400X under the microscope.

Most phytoplankton are too small to be individually seen with the unaided eye. However, when present in high numbers, their presence may appear as discoloration of the water (the color of which may vary with the phytoplankton present). This is certainly the case in the high intertidal tide pools at Race Rocks

In the high intertidal areas of Race Rocks, there are tidepools with wide fluctuations of abiotic factors. The organisms inhabiting these pools are well adapted to these extremes. Garry talks to a biology class about some of the variables influencing these high tide pools, and the flagellated green algae living within them.

The intense green color of the pools, swirly coloration of the water and a frothy covering early in the day indicate high photosynthetic capability. These plankton have an interesting response to changing salinity referred to in the video above.

Phytoplankton, like other plants, obtain energy through photosynthesis, and so must live in the well-lit surface layer (termed the euphotic zone) of an ocean, sea, or lake. Through photosynthesis, phytoplankton (and terrestrial plants) are responsible for much of the oxygen present in the Earth’s atmosphere.

pyramdiagPhytoplankton is consumed by microscopic animals called zooplankton (these are the second level in the food chain).
Zooplankton is consumed by Crustaceans (the third level in the food chain).
Fish that eat crustaceans could constitute the fourth trophic level, while seals consuming the fishes are the fifth.
A major reference work on this species may be found at :

Domain:  Eukarya
Kingdom:  Protoctista
Division:  Chlorophyta
Class:  Prasinophyceae
Order:  Pyramimonadales
Family:  Pyramimomonadacea

Genus Pyramidomonas or Pyramimonas
Species unspecified

Photos below by Garry FLetcher of Laura Verhegge’s class.

taxonomyiconReturn to the Race Rocks Taxonomy and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams. Oct.2005Astrid Raquel Argueta PC yr 31