AOTW Animal of the week: Blue Sea Slug

Animals are multicellular, eukaryotic organisms belonging to the kingdom Animalia or Metazoa. They range in complexity from simple organisms like ants to the highly developed human beings. Animals are beautiful, some are scary, while others are fascinating, many are breathtaking and a few are majestic, but most of all, THEY ARE AWESOME! 'Animal of the week' posts will let you and us appreciate and explore the wonderful nature of earth. This will include animals that you may or may not have heard of. There are over 30 million species on our planet, why not get to know some of them? I hope you enjoy reading through it as much as we enjoy writing about animals.

The Blue Sea Slug, also known as the blue dragon, blue ocean slug, blue glaucus, sea swallow, sea lizard and not to mention it's binomial name Glaucus atlanticus. Woah! That's a tricky one for the tongue!

Order: Nudibranchia
Family: Glaucidae

Habitat: Temperate and tropical waters of Atlantic, Pacific and Indians oceans.

Length: 10-30mm

Characteristics: Silvery grey on its dorsal side and dark and pale blue ventrally. Has up to 84 cerata - outgrowths on the upper surfaces of the body. It has six appendages which branch out into rayed, finger-like cerata and they float upside down.

The cerata is armed with nematocysts (stinging cells) which are absorbed from cnidarians they eat. Blue dragon feasts on other pelagic organisms such as Violet Sea Snail, Velella, Blue Button Jellyfish and the venomous Portuguese Man of' War. The stinging cells are acquired from Portuguese man of war and stored in special sacs called cnidosacs at the tip of their cerata. Tom Thompson and Isobel Bennett reported that the sting is more painful than they would have been on the Portuguese Man o' War as the blue dragon is able to select the most excellent ones and leave the less refined.
Additionally, one might say the blue dragon is a 'text book' example of counter-shading (a form of camouflage). Their foot and undersides of the cerata is blue or blue/white to avoid predation (sea birds) from above. Their dorsal surface is silvery grey to efficiently camouflage from fish looking up from below.

Does the blue sea slug remind you of a creature from world of war craft? What animals fascinate you? Leave a comment below to ensure a animal of your choice is in the next animal of the day.


Over and out.

For all the information used in this text and more visit these websites: 
Sea Slug Forum
Natural History Museum - Glaucus atlanticus (blue sea slug)

No comments

It's all about breathtaking and blockbusting science here on BioBunch. If you have an idea on what should be featured on the blog, leave a comment below... or just leave one to say hi!
Looking forward to hearing from you and enjoy the blog

Back to Top