Common Coral Weed

Description:

Corallina officinalis is a calcareous red seaweed which grows in the lower and mid-littoral zones on rocky shores.... It forms calcium carbonate deposits within its cells which serve to strengthen the thallus. These white deposits cause the seaweed to appear pink in colour, with white patches where the calcium carbonate is particularly concentrated, such as at the growing tips. The calcium carbonate makes it unpalatable to most rocky shore grazers. (Wikipedia) NB: The last three photos show the seaweed in its more calcified form, which I observed mainly in the flowing water channels carved across the rock platform. It was firm and spongy as opposed to the softer, younger specimens found in the rock pools.

Habitat:

It is primarily found growing around the rims of tide pools, but can be found in shallow crevices anywhere on the rocky shore that are regularly refreshed with sea water. (Wikipedia) This spotting was found growing in the rock pools at North Avoca Beach in NSW, Australia. High seas had flushed these rock pools out and the water was clean and clear. Corallina officinalis is a common species in many countries around the world.

Notes:

An interesting reference that describes the characteristics and habitat of macroalgae, including red algae.... https://thefishsite.com/articles/macroal... General information on marine algae.... A: http://www.fish.wa.gov.au/documents/recr... B: http://www.flora.sa.gov.au/efsa/algae_re... C: https://www.researchgate.net/figure/6-Co...