Top 10 Most Amazing Sea Slugs

All my younger years were spent outside, in the garden generally playing on my own. (I was never a people person when I was young) and sorry to tell you this, but I was also one of those kids that loved all things slimy! For me, slugs and snails but no puppy dog tails were my friends, they were always happy to be on me, leaving their slimy trail on my arm. But now as an adult, I understand that it was in fact quite gross, and I also understand that slugs are hated by gardeners and most adult minds! Poor slugs. But it seems that the slugs that live in the sea are far more amazing than their ground-based counterparts could ever be, so grab a snorkel as we take a trip to the oceans and seas to find out what is…


Top 10 Most Amazing Sea Slugs


Cyerce nigricans
Cyerce nigricans

10 – Cyerce nigricans

seaslugforum.net: Although most species of Cyerce, and the related genus, Polybranchia , are cryptically coloured, Cyerce nigricansbreaks the rule. It is one of the ‘icon’ species of the Great Barrier Reef, often being used in tourist posters and brochures. As with many brightly coloured sea slugs, this species produces distasteful secretions, and the cerata are easily cast (autonomy)when the animal is disturbed.Distasteful secretions and autonomy are two common defensive strategies sea slugs use against predatory fish.

Nudibranch
Nudibranch

9 – Nudibranch

seaslugforum.net: Nudibranchs live in oceans all over the world. These often brilliantly coloured animals are related to snails and slugs, and there are thousands of species of nudibranchs. There are two main types of nudibranchs – dorid nudibranchs, which have gills on their posterior (back) end, and eolid nudibranchs, which have obvious cerata (finger-like appendages) on their back.

Nembrotha Kubaryana
Nembrotha Kubaryana

8 – Nembrotha Kubaryana

seaslugforum.net: This relatively large species, sometimes growing more than 5 inches long, seems to range in colour. Essentially black with green pustules, or green longitudinal ridges, there is a bright orange border to the foot and around the oral lappets. In some specimens, the rhinophores and gills have orange markings but in others, these are green. In Western Australia, the black background region can have pinkish orange spots or elongate marks.

Chromodoris lochi
Chromodoris lochi

7 – Chromodoris Willani

seaslugforum.net: Of these whitish species with three black lines, the most characteristic feature of Chromodoris lochi is the plain coloured gills and rhinophores which range in colour from a translucent straw colour to dull orange or pink.

Chromodoris reticulata
Chromodoris reticulata

6 – Chromodoris reticulata

seaslugforum.net: The animals perform dual sexual roles during copulation. They give sperm to a mating partner while simultaneously receiving sperm, which they store for later insemination. Scientists observed sex between sea slugs that they had captured during scuba dives and held in a tank. After each coupling, which lasted between dozens of seconds and a few minutes, every slug discarded its…”bits” – a thread-like organ that it projects from its side into a partner’s “hole”.

Nembrotha Cristata
Nembrotha Cristata

5 – Nembrotha Cristata

Seaslugforum.net: Similar in size and colour to Nembrotha kubaryana, its main point of difference is the green border to its foot. It also feeds on a green compound ascidian which Willan & Coleman (1984) identify as Eudistoma olivaceum. Perhaps this is a biological difference from Nembrotha kubaryana, which is shown feeding on a blue solitary ascidian.

Elysia crispata
Elysia crispata

4 – Elysia crispata

seaslugforum.net: Large elysiid, up to 50 mm long and 30 mm wide with prominent parapodia which are very folded at the edge, with both primary and secondary semipermanent folds. The parapodia on each side fuse just in front of the pericardial hump, to form a barrier between the head and the pericardium. The green colour in E. crispata is much more localised in certain areas of the body than in E. clarki. The dorsal surface between the parapodia of well-fed E. crispata is generally green, interspersed with much larger white spots which, unlike those of E.

Hypselodoris apolegma
Hypselodoris apolegma

3 – Hypselodoris apolegma

seaslugforum.net: Hypselodoris apolegma differs from H. bullocki mainly in colour. The background colour is a rich pinkish purple with a white border to the mantle. At the edge of the mantle, the border is solid white but inside this is a region of varying width in which the white forms a reticulate pattern gradually merging into the pinkish purple. The rhinophore stalks and the base of the gills is an intense purple, the rhinophore clubs and the gills are orange-yellow. I can find no anatomical grounds to place this ‘species’ in the genus Risbecia.

Philinopsis gardineri
Philinopsis gardineri

2 – Philinopsis gardineri

seaslugforum.net: The Aglajidae are all carnivorous hunters, and species of Philinopsis are usually found burrowing in sand or sandy mud. There are two groups of species at present placed in the genus Philinopsis. The “typical” group, represented by Philinopsis cyanea , have a large partially eversible buccal bulb which is used to catch the bubble shells and other opisthobranchs which are their prey. Philinopsis gardineri represents the second “atypical” group which have a long muscular, tubular buccal bulb.

Glaucus atlanticus
Glaucus atlanticus

1 – Glaucus atlanticus

seaslugforum.net: Glaucus atlanticus and its close relative,Glaucilla marginata, live in close association with what Sir Alistair Hardy described many years ago as “The Blue Fleet” – the siphonophores such as Physalia, Velella, Porpita and the other associated animals including the “Violet snails” of the genusJanthina. All these animals float on the surface of the ocean being carried by the currents and the winds. Most of us are only aware of their existence when days of onshore winds blow great fleets of them on to the beaches, causing pain and angst for swimmers.

189 thoughts on “Top 10 Most Amazing Sea Slugs”

  1. Just wanted to let you know that # 7 contains false information. It’s is in fact a Chromodoris Willani, not Lochi.

  2. Wow how amazing is nature. So strange how we as children loved certain things, for me I had a pet chameleon now as an adult I actually find then very queasy. It’s that the right word. Anyway again a great posting. Ivan .

  3. First time I discovered nudibranchs was on an issue of Time magazine, and it was love at first sight. Several years later, I went to Indonesia, and I prayed as hard as I could to pleeeeeze oh pleeeeeze be led to a nudibranch. I saw two #5s on a really barren stretch right before I got to all the good coral formations, where I’m quite sure I would’ve never been able to see the little guys. How happy was I?! Thanks for posting these and leading me down memory lane too. :-))

  4. Great list Russell, I love sea slugs. I have a few photos of Nudibranch from the Red Sea when I’ve been scuba diving, not easy to find though as they are so tiny, but cute little things. 🙂

  5. Being from the northwest wet of the USA, I do not enjoy the slugs of our area (really, quite ewwww! lol) but I have to admit sea slugs seem fascinating with all the vibrant colors. An interesting 10 ten list indeed. =)

  6. And so you did. 😀 I feel the World is AWESOME and we do not even begain to know it all. I did share, maybe start a Great Conversation on twitter tonight. LOL

  7. When I was little I would collect snails and slugs and keep them in jars (a bit cruel but I didn’t know at the time)! These images are amazing, some of them don’t even look like slugs! Beautiful creatures. I really like your blog, very unique 🙂 x

  8. After a lot of looking around other sites I found seaslugforum.net THE leading authority when it comes to these incredible creatures, it is indeed a silly name that also made me laugh, but when it comes to the facts they are second to none.

  9. I have never, ever liked slugs. Yuck. However, this past October I saw the documentary “The Last Reef,” and many of the sea slugs you have posted were also in the film. They are so stunning! I never thought I would say that about a slug. 🙂 Nice post!

  10. Wow! What an incredible range of colours and shapes. I have to admit that I found the fact that there is a website called seaslugforum.net highly amusing at first, but as I went on had to respect their detailed scientific descriptions. The pictures were all amazing. A really different post to normal.

  11. yep, I’m running 24g JBJ Nano tank. With advancement in lighting, led, & filtration, you are now able to keep things that once requried giant water tank system, down to something as small as a 12g nano tank. Maintenance is next to nothing. I do water change once/year. Check it out man.

  12. I presume they are all poisonous ? because bright colored species like forest frogs and snake are rich in poison . Just a wild thought of eating them , or maybe I’m just hungry.

  13. Reblogged this on Professional Swimming Pools are servicing, maintaining and consultants to London's Swimming Pool Owners and commented:
    For a change, decided to re-blog an excellent article on Nature. Just to say that we are interested in other things in life other than swimming pools. Have a good Friday.

  14. Truly they are the most amazing one’s, indeed the top 10. And that you have mentioned that you chose the best of them, i wonder which ones are left and unseen.
    Regards

  15. I’m sure these are quite beautiful if you happen to see one while snorkeling…….but just looking at the pictures kinda gross me out! Beautiful pix though.

  16. As a kid growing up in Seattle, we had our share of slugs – when I stepped on one – yuck! They squished through my toes and the slime never seemed to wash off until I had a bath.

    How delightful to see what wondrous creatures slugs are underwater – the colors, patterns and shapes are so amazing.

  17. You’re so right! Incredible colours and shapes…Wonders of the natural world…Not many designers would come up with such shapes and colours.

  18. my kids and agree we love the pinkish purple the best…one of my boys noted the “french fries” on the top … time for supper! … thanks again for sharing!

  19. I see one image do well on a social media site,Facebook for example and then try and find 9 more just like it! Sometimes it works and many times it doesn’t. It really is a matter of luck.

  20. I did enjoy it and obviously many more people did also. I agree with thurday being a big day, the weekends are usually pretty quiet.

  21. I know, tell me about it! And thank you, I took a while to make this post to try and make sure the data was 100% right, so it seems it payed off. Good to hear you enjoyed this one, because for me it was a big one. Always a big one on Thursdays, it is the biggest day for blog! (not the weekend like people think)

  22. wow, who would have thunk?? they are all so pretty and different! really nice Russell, I love education and beauty all in one 🙂

  23. Oh wow! I love them all except for number 1 – it looks too much like a scorpion or something for my liking! I’ve actually seen a nudibranch, although it didn’t look quite the same as the one you have here – the one I saw was orange and white, and very small – we had to look closely.

  24. These creatures are amazing! I’m also amazed at the marine biologists who classified their different distinctions. I agree, they look more colourful than their ground counterparts.

  25. Ahh! If you look some of them up, most of the ones shown here are really tiny, some not even an inch long. So not dangerous acid trip seas at all, just amazing tiny creatures.

  26. Reblogged this on Synthesis and commented:
    In keeping with the recent posts on animal appearance, you’ve got to see the incredible photos in this post!

  27. Gorgeous pictures! Makes me want to go diving soon! I am sorry, but I used to pour salt on your friends the garden slugs and watch them shrivel.

Which one did you like?