Why do Midas blennies come in many different colours?

[i cant think]

This is a question that has been in my head a lot, coming in and out. What is it that makes a Midas blenny change colour? And I don’t mean stress but I mean, 24/7. You see Escenius midas most commonly labelled as “Blue Midas Blenny”, “Gold Midas Blenny”. I saw a thread about a Midas blenny gthat went a very deep red shade, the theory about that was because the midas was under red, blue and white lights with red being rather high along with blue. However, you’d think with heavy blues and lower white/red/greens you’d have a deep blue Midas, this isn’t always the case though.

I thought it would potentially be surroundings but again, I saw a bright gold midas and a blue Midas right next to eachother, tanks set up the same way in the LFS. Both had a green/blue fake plant and a piece of rock in them.

So, what is it that actually changes their colour other than stress?

Here’s just some different colours Midas blennies can be:

 

[A Young Reefer]

Midas blennys or blennys in general are known to color shift routinely. Midas blennys are capable of changing between gold, yellows, orange, red-brown, and dark browns. Darker colors are in-fact stress. For the other colors its said that it has something to do with surroundings. for example; I once saw someone that added lyretail anthias and his midas changed colors to orange after that. Some fish from the coast of Africa have a purple coloration instead of yellow.
My lawnmower blenny changes its coloration from browns to black to whites through out the day.

 

[Steve and his Animals]

For Midas blennies specifically, as far as I know, it's based on locality. Those from Africa are usually brighter yellow/gold than those from other countries/islands/seas.

It's like the regal angel, those from the Red Sea and Indian Ocean are typically yellow bellied, those from the Indo-Pacific are grey/blue-bellied, and they interbreed where their populations intersect. I'm not sure if there's any research on this topic, although I vaguely remember a Reef Builders article mentioning the two regal colorations may actually be described as subspecies in the future based on genetic data. Not sure if that will be the case with Midas blennies, but anything's possible.

If you really want to be blown away by regional variation, look at the Temminckii fairy wrasse.

3.2 Fairy Wrasses: The temminckii group | Reef Builders | The Reef and Saltwater Aquarium Blog

The temminckii group plays host to some of the genus’ larger and more unappealing species. Burley, pugnacious and often glazed in matte grey, these un-fairy looking fairy wrasses are more often than…

reefbuilders.com

Four regional variants of that species alone, and that was back in 2015.

 

[i cant think]

For Midas blennies specifically, as far as I know, it's based on locality. Those from Africa are usually brighter yellow/gold than those from other countries/islands/seas.

It's like the regal angel, those from the Red Sea and Indian Ocean are typically yellow bellied, those from the Indo-Pacific are grey/blue-bellied, and they interbreed where their populations intersect. I'm not sure if there's any research on this topic, although I vaguely remember a Reef Builders article mentioning the two regal colorations may actually be described as subspecies in the future based on genetic data. Not sure if that will be the case with Midas blennies, but anything's possible.

If you really want to be blown away by regional variation, look at the Temminckii fairy wrasse.

3.2 Fairy Wrasses: The temminckii group | Reef Builders | The Reef and Saltwater Aquarium Blog

The temminckii group plays host to some of the genus’ larger and more unappealing species. Burley, pugnacious and often glazed in matte grey, these un-fairy looking fairy wrasses are more often than…

reefbuilders.com

Four regional variants of that species alone, and that was back in 2015.

Wrasses I’m not surprised with when it comes to varying colours but blennies I do get intrigued by.

 

[Lsuhunter]

Mine is more of the yellow/pink one but it is so cool when he goes to bed. He backs into his hole and changes his face to camo to blend in with the rock he sleeps in.

 

[Steve and his Animals]

Wrasses I’m not surprised with when it comes to varying colours but blennies I do get intrigued by.

What makes you say that?

 

[maroun.c]

+1 on origin and I've noticed that in couple shipments I saw in LFS.

 

[blaxsun]

It's a common misconception that midas blennies always change color due to stress. Sometimes they just change color because because they're bored or have nothing better to do...

Mine started out yellow, graduated to pink and is now a pretty blue-purple hybrid like the first image. Why did he change? Absolutely no idea. But he's a lot stealthier now...

 

[Spare time]

The "how" is easier to study than the "why" unless someone does a comparison of environmental and social factors between populations of different colors. You might be able to find something by digging through a ton of academic papers but it might be difficult. As for the "why," my default guess is random but harmless mutations that spread through a population. However, color is often communicative (or the complete opposite which is to not be noticed), so that is another possibility. Or, it could simple be linked to some other genes that were selected for and these just so happen to become altered as a result of how genes are very intertwined with one another.

 

[i cant think]

What makes you say that?

It’s more well known when it comes to wrasses having many variations, the teminicks was a good example, another example of it is the Scott’s wrasse.

 

[Polyp Punk]

This is a question that has been in my head a lot, coming in and out. What is it that makes a Midas blenny change colour? And I don’t mean stress but I mean, 24/7. You see Escenius midas most commonly labelled as “Blue Midas Blenny”, “Gold Midas Blenny”. I saw a thread about a Midas blenny gthat went a very deep red shade, the theory about that was because the midas was under red, blue and white lights with red being rather high along with blue. However, you’d think with heavy blues and lower white/red/greens you’d have a deep blue Midas, this isn’t always the case though.

I thought it would potentially be surroundings but again, I saw a bright gold midas and a blue Midas right next to eachother, tanks set up the same way in the LFS. Both had a green/blue fake plant and a piece of rock in them.

So, what is it that actually changes their colour other than stress?

Here’s just some different colours Midas blennies can be:

My new midas looks like the first top pic. Bought it as an African gold midas but it’s blueish :/ . Is that it’s tru color or can it turn back peachy/yellow?

 

[i cant think]

My new midas looks like the first top pic. Bought it as an African gold midas but it’s blueish :/ . Is that it’s tru color or can it turn back peachy/yellow?

I think it is, I’m pretty sure under a certain environment it will change its colour. I haven’t heard of one changing back but there seem to be only a couple cases of these fish changing colour if they were bought as a yellow Midas.
I think many of the midas blennies from Africa are blue but I could be wrong. It’s definitely something to do with what colour some of the fish around them may be.

 

[blaxsun]

I think it is, I’m pretty sure under a certain environment it will change its colour. I haven’t heard of one changing back but there seem to be only a couple cases of these fish changing colour if they were bought as a yellow Midas.
I think many of the midas blennies from Africa are blue but I could be wrong. It’s definitely something to do with what colour some of the fish around them may be.

You can add mine to the rare case list. Started as #2, progressed to #3 and then finally changed to #1. All probably within 4-6 months of first receiving him.

Environmental conditions? Well, he's practically spent 24/7 the past year in a barnacle. This fish is lazy as F.

 

[Saltyanimals]

Had nooooo idea they came in non-gold colors. I think I want a blue one now.

I wonder if I can put some green food coloring in a QT and make a green midas. Will call him Ultra Hulk-Midas and sell him for a mere $2k a fish.

 

[The Dude Abides]

Mine started off gold when I purchased him, turned blue and now is gold/pink after I added some Bimac anthias to the tank.

 

[Slocke]

An obvious one but I’ve noticed a color change based on diet. I feed flakes with high algae content among various frozen carnivorous foods. However if it goes a few days without those flakes it goes brown.

 

[Tamberav]

I thought I read somewhere they mimic anthias. Figured it may be based on that.

 

[Lavey29]

Mine was pale white at the LFS but he swam healthy. I've had him like 4 months now. He is deep yellow orange color and swims the tank all day. Biggest food eater in the tank. Dives into his rock hole tail first to sleep. Model citizen but doesn't back down to any fish in the tank.

 

[Saltyanimals]

+1 on that Anthias mimic fish comment

Mine was very timid while in QT and never quite settled and was reluctant to be out in the open much at all. There were 5 other fish non aggressive fish in there with him. However he was out and about swimming almost immediately when I introduced him to DT where there were 6 other open swimming anthias flying around. This goes back to fish feeling safe and swimming amongst other fish versus when they see a very quiet environment that may suggest other fish friends are in hiding due to a predator.

I see what I suspect to be a lymphocystis on his fin which should clear up on his own I hope. This is my THIRD midas after losing the first 2 to jumping. I had a lid but did not fully close it both times. Lesson(s) learned so please lid your tanks if you have these guys.