Anglerfish Caught Boning For The First Time (NSFW Video Included!)

Many of you may have heard of anglerfish, a group of often scary and alien looking fish lurking in the deep blue. But I bet most of you don't know how these fellas reproduce. So, let's start with the basics. 

Here's a photo of a typical female anglerfish:

 
Female Humpback Anglerfish - Melanocetus Johnsonii, (CC BY-SA, credit)

And now here's a sketch, showing both a female and a male anglerfish:

Triplewart seadevil - Cryptopsaras couesii, (CC BY-SA 3.0, credit)

As you can see in the sketch above, anglerfish are often sexually dismorphic, with males being dwarfed by their females counterparts. 

For example, female Cryptopsaras couesii, or the Triplewart seadevil as it is commonly known, routinely reach sizes of 30 cm long, with males being barely 1 cm long! Furthermore, males essentially act as parasites, fixing themselves on the body of a female for their entire lives! They can't even feed themselves as they lack a functioning digestive system and get all their nutrition directly from the circulatory system of the female host! Their only role is to provide the sperm, which to me sounds like a pretty good deal :D

Since anglerfish are deep sea creatures there are only a handful of videos showing them in their natural habitat and as of today nobody had captured footage showing a couple in action. Actually, most of our knowledge comes from dead specimens, often in really bad shape as they are washed ashore or found as by-catch in nets. 

But all this changed two days ago, with a video released by a couple of deep-sea explorers, Kirsten and Joachim Jakobsen. Please remove any minors from the surrounding area before clicking the play button:

The couple took the video at a depth of 800 meters with their submersible, during a dive along a steep deep-sea wall on the south side of São Jorge Island. They were about to surface after 5 hours of exploring, but at the last moment  “something with a funny form” caught their attention and they decided to stalk it. 

They followed the creature for 25 minutes before finally surfacing. Later, they send the footage to Ted Pietsch, a deep-sea fish researcher at the University of Washington in Seattle who identified the species as Caulophryne jordani, commonly known as the fanfin angler mainly found at depths ranging from 100 to 1,510 metres. And that is pretty much the story behind the video.

Fun Fact: The name Caulophryne originates from the greek word 'kaulos' or 'caulis' which translates to stem. It's fun because in modern slang Greek it essentially means dick :D 

Since we talk about anglerfish, let me tell you another cool fact about these creatures that you might not know. First, scroll a bit up and have a good look at the sketch again. Notice that weird appendage-like structure on their head? Any idea of what it might be?

So, here's the deal. All anglerfish are carnivorous. This appendage thingie is called esca and it's something the females of most anglerfish species have on their head and essentially acts as a fishing rod! With the help of symbiotic bacteria, the end of this organ in some species even glows like a light bulb and attracts small fish and other curious prey, usually right in their huge mouth. It is also hypothesized that it might grab the attention of males seeking for a mate.

They can even actively move the esca to further peak the interest of potential prey, as you can see in this video...

...and in this video XD

This predation method is also why they are commonly known as "Anglerfish".

And here's a final interesting fact about these creatures. As mentioned before, most of them are deep sea creatures, living in the bathypelagic zone, at depths of 1,000 meter or greater. In this zone, light is essentially non existent and as a result only a few creatures hang around, hence prey comes in their jaws only so often. For this reason,they have come up with a really cool adaptation.  

Their mouths are very  large which combined with an extremely elastic stomach allows some species to swallow prey twice their size, curbing their appetite for a long, long time until they get a chance to eat again. This is also why the spend much of their life motionless, as in the first video. Preserving every last bit of energy matters!

And that's pretty much all the really cool things about anglerfishes. In total, there are over 210 verified species, and you can find numerous of them in varying depths in every sea of the world. Here's a link to wikipedia if you want to learn more about these creepy creatures, it's a good start.

I will tell you goodbye with some more amazing footage, this time from the Monterey Bay Aquarium Research Institute. Enjoy:

 

  

And here's a totally random cute video to counteract all the creepiness you got from this post:

Enjoy the weekend !

References & Further Reading

 - All references are provided in the form of clickable links in the main body of the post :)