April’s Anemones

April’s anemones!

Sea anenomes are in the phylum cnidaria, like jellyfish. Sea anemones attach themselves to rocks with their adhesive foot, attacking prey as they go past with their stinging tentacles. Their tentacles have cells that contain toxins that, when touched, shoot out venom that paralyse the prey. The anemone then uses its tentacles to bring the prey into its mouth.

With over 1000 species of sea anemone, they range from 1/2 inch across to 6ft!  They can be found all over the oceans.

On the HMS Challenger expedition, several species of sea anemone were dredged and trawled. Take a look at some of the plates found in the reports below..

DSC_0056
Plate 1 from the Challenger Actiniaria report. Showing genera such as Porponia, Cercus and Paractis.
DSC_0059
Plate 2 from the Challenger Actiniaria report. Showing genera such as Corallimorphis, Polysiphonia and Bunodes
DSC_0063
Plate 3 from the Challenger Actiniaria report. Showing genera such as Stephanactis, Amphianthus and Ophiodiscus

One species of anemone found on the expedition was Calliactis polypus. They were found on station 208 on January 17th 1875 at 18 fathoms and also at St Vincent, Cape Verde. They were all found on gastropod shells that hermit crabs were living in. This is because the anemone gets to live and feed on the shells in return for protecting the crab. The anemone isn’t naturally attracted to the shells but the hermit crab will persuade the anemone to fix itself on to the shell by tapping on the shell so the anemone relaxes.

Project update!

We are moving a long at a nice pace with the Challenger Project – with the help of many museums we are starting to collect a large amount of Challenger material which I am currently sorting to go on our database. If all deadlines are stuck to, the website/database should go live at the end of September this year. Keep  your eyes peeled!

Me at Bristol Museum photographing Challenger material
Me at Bristol Museum photographing Challenger material

In next month’s blog I will be reading up on the narratives and diaries of HMS Challenger and will be looking in to the dark side of the voyage where all was not going well..

Leave a comment