Hylas's isopods

Isopod fancy breeder and genetics enthusiast. Porcellio scaber appreciator.

[hylasregillasisopods]

Pinned post/introduction

I'm Hylas, based in the northwest USA. I've been in the hobby since 2020. This is a blog to record and share my discoveries in isopod breeding.

Fair warning, posts here may be poorly written and rambly. Things like line tracking and preservation of hobby history are very important to me and the goal here is to make as much of my information available as possible. I'd rather write something down poorly than not write it down at all.

Any images I upload here can be reposted freely for educational or archival purposes. As long as you're acting in reasonable good faith, I'm cool with it.

I occasionally post about my adventures with other crustaceans (namely amphipods). Those posts will be tagged accordingly as "#other bugs"

Sad/bad news posts will be tagged as "#isopod sadness"

Seeing as this is a bug-focused blog. I currently only cw tag (#crowded bugs and #bug closeups) on original posts, not reblogs.

I'm happy to add more organizational or content warning tags on request.

[hylasregillasisopods]

Piebalds are growing well

[hylasregilla]

What in The fuck? My Cubaris sp. 'rubber duckies' seem to have thrown a clutter with white markings?

Low quality pics because it's so hot I can't be fucked r/n.

[hylasregillasisopods]

I haven't been active on here in a long time - mostly because my projects have been going badly - but look what I found this evening. Has anyone seen this before?

[isopods-daily]

Brackenridgia heroldi

[crevicedwelling]

here’s a fun Porcellio scaber mutation! the base color is recessive orange, which usually turns all gray pigments orange, except this strain has wildtype gray spots. it’s not a variant of calico since these breed true to orange and have orange eyes.

I have no idea what’s causing this or how it inherits, but it does seem heritable. my one very speckly female, now deceased, had a number of plain orange offspring, but I discovered at least one has her spots! well, she’s got *one* spot.

I wasn’t expecting results at all, but plan to follow through with the project since it’s a very unique morph. this female is gravid so perhaps I’ll know more about it soon

[crevicedwelling]

here’s the old sow who started this strain (and one of her males). if only she lived long enough for me to get her with my macro lens… a truly impressive animal, ancient and massive and mysterious

[hylasregillasisopods]

No pics today, just an update. I found another female 'dark orange' scaber and what I think is a dark orange male (might just be regular orange, I haven't looked at him in high light yet) two weeks ago in the same spot where I caught the OG. Today I noticed the female has dropped a litter of mancae. :)

Even though these new ones are definitely related, any genetic diversity at all is very welcome. It's also comforting to know that the morph is out there in my yard still, in case something goes wrong.

[crevicedwelling]

Porcellio scaber “White Noise,” a morph that I bred last year from a cross involving “Dalmatian.” like “Dalmatian” P. scaber, most of the body lacks pigment, but “White Noise” reduces the pigmentation even further, resulting in very tiny markings, if any. the name (suggested by someone on Tumblr!) comes from the staticky appearance of the variegated eyes, a trait I don’t think I’ve seen in any other mutation.

I am in the process of breeding out the “Dalmatian” gene to figure out what the mutation responsible for the reduced pigment and eye variegation looks like in an otherwise normal isopod.

[crevicedwelling]

here’s a typical “Dalmatian” morph, with normal eyes and more pigment patches.

and a “White Noise” next to a wildtype, or whatever passes for that around here (everything seems to be some sort of mottled)

[hylasregillasisopods]

i would absolutely buy captive bred colorful amphipods from you, just fyi. assuming you could ship them anyway

I'd love to do that someday!

I'd need to get a proper handle on care and transport before I feel comfortable shipping them. These are the only amphipods I've ever kept, but they seem slightly more sensitive to new water than the Gammerus species that're popular in the aquarium hobby. I'm thinking about doing some test shipping (packaging them up as if you were going to ship them and leaving the box in a garage or shed for a few days) to see what they can handle.

If you're into amphipods feel free to get in touch. I really like them but there's not much of a community.

[hylasregillasisopods]

trip to Thailand < flipping cardboard in my dad's compost bin

[hylasregillasisopods]

Porcellio scaber 'dark orange' project update

F2

The orange did indeed prove out! I've separated the f2 generation into their het and homo groups. I lost the paper I was keeping count on, but I remember the ratio being consistent with my 50/50 expectation.

Here they are! My camera really wanted to enhance the orange. The video still on the right is more accurate.

Their coloration is noticeably grainy and looks darker than regular 'orange' to me, but I might be imagining things. There's not too much variation.

Dark Orange X Spanish Orange

Now HERE'S where it gets interesting! The 'Dark Orange' X 'Spanish Orange' cross was a little test breeding meant to verify whether the same recessive amelanism gene was responsible for the orange color in both morphs. I expected to see either all grey (meaning they were separate genes) or all orange (meaning they were the same). What I didn't expect to see was three distinct phenotypes.

There's the classic orange that I expected, a browner/darker orange, and three greys for some reason.

So YES! The classic recessive amel gene is responsible for the orange in 'dark orange'.

But did the 'dark' gene just prove out? Is it a dominant or co-dominant allele? Idk! I have to wait until the homozygous f2s are bigger to see if all or any of them share this trait. Their having grainy coloration and being mixed ages makes it frustratingly difficult to tell at this stage.

I attribute the even coloration of this test cross to the 'Spanish Orange' side of the family, since pure Spanish Orange stock is known for its smooth coloration.

Now to address the greys. Yeah, I don't know what happened here. The mother has been isolated with the progenitor in a harem setup since way before she was sexually mature. The only thing I can think is that one of the f2 sons managed to breed with her before I removed them. I'm not sure how that's possible as I removed them when they were absolutely tiny but it's the most likely explanation I can think of. I've separated the three greys into their own bin for now. Maybe the answers will be further down the road.

Unfortunately, I can't find the original dark orange male who started all this. I'm not sure if he passed away or if he somehow eluded me when I sifted. Wherever he is... o7

[hylasregillasisopods]

Porcellio scaber 'dark orange' project update

F2

The orange did indeed prove out! I've separated the f2 generation into their het and homo groups. I lost the paper I was keeping count on, but I remember the ratio being consistent with my 50/50 expectation.

Here they are! My camera really wanted to enhance the orange. The video still on the right is more accurate.

Their coloration is noticeably grainy and looks darker than regular 'orange' to me, but I might be imagining things. There's not too much variation.

Dark Orange X Spanish Orange

Now HERE'S where it gets interesting! The 'Dark Orange' X 'Spanish Orange' cross was a little test breeding meant to verify whether the same recessive amelanism gene was responsible for the orange color in both morphs. I expected to see either all grey (meaning they were separate genes) or all orange (meaning they were the same). What I didn't expect to see was three distinct phenotypes.

There's the classic orange that I expected, a browner/darker orange, and three greys for some reason.

So YES! The classic recessive amel gene is responsible for the orange in 'dark orange'.

But did the 'dark' gene just prove out? Is it a dominant or co-dominant allele? Idk! I have to wait until the homozygous f2s are bigger to see if all or any of them share this trait. Their having grainy coloration and being mixed ages makes it frustratingly difficult to tell at this stage.

I attribute the even coloration of this test cross to the 'Spanish Orange' side of the family, since pure Spanish Orange stock is known for its smooth coloration.

Now to address the greys. Yeah, I don't know what happened here. The mother has been isolated with the progenitor in a harem setup since way before she was sexually mature. The only thing I can think is that one of the f2 sons managed to breed with her before I removed them. I'm not sure how that's possible as I removed them when they were absolutely tiny but it's the most likely explanation I can think of. I've separated the three greys into their own bin for now. Maybe the answers will be further down the road.

Unfortunately, I can't find the original dark orange male who started all this. I'm not sure if he passed away or if he somehow eluded me when I sifted. Wherever he is... o7

[crevicedwelling]

Can you identify what kind of isopod this is? I'm unsure if it's a yellow morph or a species I don't immediately recognise. Location is South East England, and if it helps they were incredibly speedy and more evasive than the porcellios and armadillidium I've seen. Thank you in advance!!

a rare yellow form of Philoscia muscorum! the species is known for being swift and wary. unfortunately, they don’t seem to come in yellow where they’ve been introduced in the US, so I’m jealous of that little canary!

Philoscia muscorum | British Myriapod and Isopod Group

(this page has photos of various color forms!)

[hylasregillasisopods]

Dark Orange f2 does contain amels! Will be separating, counting and photographing them later today. Expect an update soon! <3

[hylasregillasisopods]

Look at this beautiful man.

[hylasregillasisopods]

"Dark Orange" has an f2 generation now. No signs amelanism in the babies from what I can see, which I'm honestly a little surprised about.

His amel mate is about to drop her litter soon too, so that should prove or rule out the hyperpigmented amel theory.

[hylasregillasisopods]

It's difficult to get the Eluma caelata fuzz to appear on camera, but under a strong flash they sparkle ✨️

[hylasregillasisopods]

Some more observations and speculation.

Yes, you can feel the fuzz. It's like a flocked toy but on such a small scale that it feels smooth. In practice, it makes the pods a bit slippery.

They're not as defensive as Armadillidium species. They're quick to unroll and don't really flee or cling. Maybe they rely on their texture making predators lose grip?

The fuzz seems to vary in prominence over time. I think it might have to do with moisture retention, like the waxy coating on Pruinosus species.

They're all brown, but the base color, marking prominence, and fuzz color do vary quite a bit.

[hylasregillasisopods]

It's difficult to get the Eluma caelata fuzz to appear on camera, but under a strong flash they sparkle ✨️

[hylasregillasisopods]

Eluma caelata "velvety pill woodlouse" babies feat. a quarter for scale.

There are at least two litters (clutches?) of them. Captive conceived. :D

I also spotted one who had just molted. Check out that fresh fuzz!