Nudibranchs

Main photo by David Borg

The pilgrim hervia is an aeolid sea slug, its average size is between 3 and 5 cm. The body is thin and slender, with a long sharply pointed tail

Above, photo by Antonio Martin

The orange horns are called rhinophores, and act as their nose—nudibranchs in general have poor eyesight, and instead use their rhinophores to "smell" their food. Their rhinophores are smooth, begin in white, changing to orange with white tips. The tusks are called oral tentacles, and are used to shovel food into their mouths. The tentacles are white, smooth, and usually a fair bit longer than the rhinophores. The mouth opening sits between and slightly below these tenacles.

The orange patch between marks where the eyes are, but I'm yet to read that the colour has anything to do with its vision. source

Above, photo by jordi benitez

Its body coloration is milky white with 8 to 10 clusters of dorsal cerata which can be bright red, purple, brown or blue, with the tips coloured in luminescent blue. [Cerata- are dorsal and lateral horn-like growths on it's upper body]

Those cerata act like gills, and each one contains a terminal outgrowth of the digestive gland, a diverticulum. (An outgrowth of the digestive gland or hepatopancreas of the animal)

Above, photo by Mario Pesce

This species occurs in the Mediterranean Sea and in the eastern Atlantic Ocean from the Channel south to Senegal. This sea slug prefers to live on rocky bottoms and slopes in clear and well-oxygenated water, between 5 and 50m in depth

The pilgrim hervia feeds on hydroids (small predators related to jellyfish)...

These look a bit like spindly underwater branches source

Above, photo by Bart

In recent years, C. peregrina has been the subject of study in "kleptopredation". This is eating food not for just its own nutrients, but for the nutrients of what the food itself consumes! In short, it was found that C. peregrina prefer consuming hydroids that have recently fed themselves (hydroids are predators too) source

Above, Cratena peregrina nudis laying eggs, Greek Aegean. Photo by Ivan Bakardjiev

Info from wikipedia, unless stated otherwise

Title photo by Carlos Fernandez-Cid

While I was reading up on information for a nudibranch post, I was surprised to learn that they are also found in UK waters. And also on occasion, we sometimes have exotic visitors like Babakina anadoni if we're lucky....

Usually, they are to be found in

....warm Atlantic waters including off the west coast of Spain, the Canary Islands and the coastlines of Portugal and rarely southern France. It is also known from the eastern Atlantic in The Bahamas, as well as the French Caribbean and the coast of Brazil

In 2022 (possibly a result of global warming) one was found much further North than it's usual range, off the Isles of Scilly, UK. It was found by Allen Murray, a volunteer diver taking part in the Wildlife Trusts Seasearch initiative where people are asked to record wildlife found during their scuba dives Source

The following year another was found even further North in a rock pool at Falmouth, Cornwall, Mainland UK!

Photo by Carlos Fernandez-Cid of B. anadoni eating Candelabrum cocksii. Cabo Udra. Ría de Pontevedra

It grows to be around 20mm long, and the ground colour of it's body is purple

[The] chemosensory organs (rhinophores) and other structures covering the surface of the body (cerata) are contrasting shades of purple as well as different colours including blue, white, yellow and pink

Photo by Carlos Fernandez-Cid

It was only described in 1979, and it was named in honour of Emilio Anadón Frutos (1917-1997)

....who was a professor of zoology and marine biology at the University of Oviedo, Spain

Photo by Carlos Fernandez-Cid

Personally, I think they look like one of those large foamy, pink shrimp sweets, with candy corn growing out of it....

Info from wikipedia unless stated otherwise

Title photo- 'A Goniobranchus kuniei nudibranch in the waters of Komodo National Park, Indonesia. Image credit: Òscar Montferrer'

I came across this article while looking for some info to answer a comment, and thought the photos were too good not to share. The article is interesting too!

Above 'A Goniobranchus geminus nudibranch in the waters of Tulamben, Bali, Indonesia. Image credit: Òscar Montferrer'

Above 'A Doto greenyamieri nudibranch in the waters of Amed, Bali, Indonesia. Image credit: Òscar Montferrer'

Above 'A Phyllodesmium iriomotense nudibranch in the waters of Amed, Bali, Indonesia. Image credit: Òscar Montferrer'

Above 'A Cyerce kikutarobabai nudibranch in the waters of Amed, Bali, Indonesia. Image credit: Òscar Montferrer'

Any errors will be mine, I couldn't do my usual copy/paste and had to type all the names and locations myself

cross-posted from: https://lemmy.ml/post/13754178

Title photo 'Cuthona yamasui, Tulamben,bali,indonesia' by Yansu JunK

Nudibranch, meaning 'naked gills' are an order of marine gastropod of over 3000 species! They breathe through a ‘naked gill’ shaped into branchial plumes (simillar to the alveoli of a human lung) but external to their bodies

Above, 'Ocellated Phyllidia, Phyllidia ocellata, Alor, Indonesia' by Jeremy Smith

They are soft bodied, slug like creatures and are noted for their bright colours and extravagant body forms. Their nicknames reflect their fabulous forms- "clown", "marigold", "splendid", "dancer", "dragon", and "sea rabbit"

Above, 'Flabellina affinis' The Mediterranean by Verheyen Stefan

They are found worldwide including the Arctic and Antarctic, through temperate to Tropical sea waters (though some species can live in brackish waters) They can be found at all water depths from warm shallow reefs (where the greatest number of species are found) to depths of 700 metres. One species was discovered at a depth of 2500 metres!

Above, 'Nembrotha kubaryana). Lembeh, Indonesia' by Trent Burkholder

Species can vary in size from 4mm to 40cm long, and are oblong in shape. They can also be thick or flattened, long or short, ornately colored or drab to match their surroundings!

Above, 'Hermissenda crassicornis, Point Defiance Marina, Tacoma' by Zachary Hawn

Their eyes are small and simple, and can only discern differences in light and dark. Instead they have tentacles on their heads which act as sensory organs being sensitive to touch, taste and smell!

Above, 'Ceratosoma trilobatum, Indonesia, South Molucces - Ambon' by divemecressi

They are carnivorous predators, usually feeding on sea sponges, anemones, corals and barnacles, although some are cannibalistic!

They have evolved defense strategies to protect them from being eaten, including camouflage to look like sea sponges, chemical defenses complete with warnings. Some species eat hydrozoids (a relation of jellyfish) and then store the stinging cells that pass undigested through their gut to their rear end...any predator trying to bite one of these nudibranchs will end up with a painful sting!

Above, 'Phideana hiltoni' by Ken Bondy

They are hermaphrodites (both male and female) and their sex organs are on the right side of their bodies. They still need to reproduce sexually though. When they meet a suitable partner they will engaged in a 'courtship dance' lasting for a few minutes. They then lay eggs in a long slimy ribbon, from as few as a couple to up to 25 million! source

Above, 'Consummation' by lee Ming

Above, 'Threesome having fun, Lamprohaminoea cymbalum, Tulamben Bali' by Ludovic

More nudibranchs to enjoy.....

Above photo by Jackson Wong

Above, 'Halgerda tessellata, Philippines - Malapascua' by divemecressi

Above photo by Carol Buchanan

Above photo by Barbara Stevens

Above photo by Joan Ribas

All info from here, here and here

As always, I'm not an expert I just like sharing fun things....any errors leave a comment, and I'll edit my post, cheers!

edit, link

Wikipedia: https://en.wikipedia.org/wiki/Chromodoris_willani Image source: https://imgur.com/gallery/b0sKKeJ

https://en.wikipedia.org/wiki/Nembrotha_kubaryana