i 💚 cool bugs

Doing my daily checks on my bins includes checking my P. Pruinosus powder blue bin for the occasional powder orange that crops up to maintain a dedicated population of the recessive trait.

This morning I spotted a baby that was friggin white!? I'm used to the blue babies looking a little orange at the start before their carapace thickens enough to show blue, and it usually shows pretty clearly under the 40x magnification.

Not this little one though. It's internal organs are still clearly orange but it's carapace is completely white. So here's my theories atm:

Occam's razor. This is a very high expression oreo crumble. Little one got the gene for the big white patches and went hog wild with it (the big giveaway here being the eyes still have pigmentation).

Much less likely, somehow something of the albinism gene that was present in my original 25 founders got passed down quietly until manifesting as a form of leucistic coloration in this little one. I'm not well versed in how the alleles for albinism work in these guys which is why this is a theory at all.

The least likely, nearly impossible, but non-zero chance that this individual is leucistic completely de novo.

Right now it's in the less populated powder orange bin so I can more easily keep an eye on it and also monitor for the non-zero chance it's a randomly very pale powder blue that will darken with age to eventually be noticable. (If so it'll go back in the blue bin hopefully before it breeds, but worst case I'll know any pale babies need to go in the blue bin too when I see them.)

So I started my isopod keeping journey just last year in mid/late May with a "party mix" of P. pruinosus. At the time I wasn't too interested in genetics, but (to keep a long story short) that rapidly changed, and by the time I really got interested, a lot of my recessive phenotypes were starting to be bred out.

Quick genetics aside for folks who may not be familiar (feel free to skip ahead if you already know this stuff), the colors and patterns I'm working with in regards to my P. pruinosus are really simple [Mendelian inheritance].

Take the two major colors as an example, and let's make B the dominant wild-type blue allele and b as the recessive orange allele. Like us, isopods are diploids, meaning they have two complete sets of chromosomes. Meaning two copies of an allele per gene, half from mom, half from dad. An isopod with BB is going to be a powder blue, and an isopod with bb is going to be a powder orange. These are considered homozygous. They have two copies of the same allele for that gene. BUT! An isopod that has Bb is heterozygous. They have two different alleles. And because B is dominant over b, they will still appear blue.

However

this heterozygous individual still has the possibility of passing on that recessive b allele.

Check out below for a quick little set of [punnett squares] I drummed up for this in Excel. You can see just how easy it is to lose a certain phenotype (or "morph." This is the actual trait we can observe.)

There's something similar going on with the spotting associated with "oreo crumble" and "orange cream" morphs of this species. I denote them as S for solid and s for spotted. (color added for visual help on this post).

So what in the everliving hell am I freaking out about?

Basically, prior to my most recent bug order, I've been trying my damndest to recover by bb ss population from what I had left in my general populations.

At first, I scrounged together everyone I could find with any sort of recessive traits and paired them up to maximize the chances that they would mate with exactly who I wanted to and give me the highest chance to get the genotypes I was looking for.

Unfortunately, the pair bins I had going had some sort of lethal flaw. Between desiccation despite constant misting and repeated failed moults, I kept losing individuals to the point I was down to just 10 mixed sex oreo crumbles (B?ss) and 3 male orange creams (bb ss).

So I revamped my setup. Instead of pair bins, I set up a full bin to allow my spotted isopods I still had to cohabit and made peace that I may end up breeding out the orange creams with plans to outcross with powder oranges in the future to try and bring them back.

But then, oh but then, on March 7th as I was doing some casual spot-cleaning in Ezra's bioactive tank I found a perfectly breeding sized orange cream female! Y'all I freaked.

And now she's pregnant????????????? PREGONATE!? GREGNANT???PREGANANANT!!!!!

And I mean early stages. Like brand fucking new. Like I needed my microscope to confirm. Buns have only just gone in the oven. Meaning she definitely got pregnant in this bin. And that means all of her offspring are guaranteed to be spotted, and at least heterozygous for orange coloration depending on the male she mated with.

Do I now have other bins that I'm outcrossing with my newest batch? Sure. And I don't regret that even a tiny bit because the influx of new genes will strengthen my population overall. But ougadskjgjkadgfgkghf it feels so good that something is actually coming out of this nearly abandoned project. I'll have another generation of gorgeous babies to further outcross with the offspring of the other bins!

Anyway, if anyone is curious about my current breeding project bins, I have them marked A-D.

A is all of my ?? ss isopods from all of my various vivariums and general population bins.

B is all male bb ss and female B? ss (likely BB ss) from my most recent order.

C is all male B? ss (likely BB ss) and female bb ss from my most recent order.

D is currently empty but currently planned to be exclusively bb ss from all of the other bins.

I know B and C are almost certainly going to result in heterozygous oreo crumbles, but imo it'll be worth it to have the increased genetic variation in other parts of their genome since I know they're from different populations. I can wait an extra generation to see more orange creams to increase the overall population health.

By the time the orange cream morph starts to be bred out of B and C, D should have a robust enough population to perpetuate itself where I shouldn't have to worry about it. And just in case it's the oreo crumbles who start to disappear (which is a non-zero chance when you're starting from a small population), bin A will be repurposed to be my dedicated oreo crumble bin.