Crustacean Adventures

Hello all! As probably none of you know (;), I have been eying crabs for a while now. No, not your typical hermit crabs or other marine aquarium crabs, though those are awesome too. Rather, my interest has grown in freshwater/brackish terrestrial crabs, specifically of the genus Geosesarma.

Bam! Surprise Photo.

I have always had an interest in these fascinating freshwater denizens, but doors started to open in regards to their availability after I saw a 1:1 pair of vampire crabs come up for sale/trade on Arachnoboards. I eagerly contacted the seller, and soon we had a trade worked out. Unfortunately, one of the specimens died before we shipped out, and since I was primarily interested in breeding them (which you can’t do with only a male), the trade fell through.

However, sometime after, I discovered one of my friend’s, also interested in the obscure invertebrates of the world, already had two species of Geosesarma! He let me know that he was able to order more, and that if I wanted some to let him know. Long story short, I ended up with 5 Geosesarma dennerle, two females and three males (the shipment was male-biased), of an odd color variation! They seem to lack a full splotch of yellow on their carapace, a usual characteristic of G. dennerle, rather appearing to somewhat retain their juvenile coloration of just splotches of yellow/whitish-grey. Then again, a few of the specimens still are juveniles starting to transfer into adulthood, so we’ll see how it pans out with them.

Geosesarma sp. definitely are on the small side, and all of my specimens are only about 1.5″ in terms of leg span (that’s about 3.81 cm for all you people on the metric system), but what they lack in size they make up for in coloration, behavior, and ease of breeding. They are one of the few crab genera to breed fully in freshwater, with the females giving birth to fully-formed baby crabs! They also are very communal, making it even easier to breed these awesome crabs in captivity.

I already had an empty 20 gallon (75.70 liters) paludarium, purpose built for vampire crabs a few months before by my insanely-skilled brother, calling for some inhabitants, so I’m sure you can guess where they are being housed…photos below!

Yellow variant.
Much lighter variant, with almost white eyestalks.
Each crab has its own personality of sorts, and this female specimen has proven to be the boldest of them all, regularly venturing out into the open. Normally they hide until the observer is gone and movement is no longer visible, but not this crab.

The paludarium. A small water feature, kept moving by the small waterfall of sorts coming out of the rock on the left, is kept hard by the presence of calcium carbonate coral sand and a few coral rocks. Soft water will lead to deformities in the crabs.

On land there is a plethora of plants, Cissus discolor, Selanginella sp., Pepperomia rosso, Epiperemnum aureum, and various other unknown plants in both the soil and in the water. My skill with plants is not where I’d like it to be yet…

Everything has been happy and growing, with one plant even flowering. The crabs have done quite a bit of rearranging however, including exposing the tubing and blue foam underneath the substrate in several areas. Also, besides eating their regular food of springtails, dwarf isopods, and biodegradable peat pots (a trick shared by the above mentioned friend), they have also decided they like the taste of both decaying and growing moss, and the leaves of the fern in the back left of the second paludarium photo. They crawl up the leaves of what looks like a lemon plant in the mid-left of the same photo, and then strip off the low-hanging fern leaves. Considering this fern has been the most sensitive and difficult plant to get growing, I can only say that I am mildly frustrated with their sudden favorite food. But just so long as the crabs are happy, I’m happy, ha ha.

And there you have it! My crustacean adventure as of now. My plan is to breed them if you haven’t picked that up yet, and hopefully start to increase the numbers of captive bred specimens available in the hobby. Hopefully by doing so more species will come into the hobby, including two of my favorites: Geosesarma borogensis and G. malayanum.

As always, I thank God for all these incredible creatures to marvel at. The diversity He created is truly breathtaking.

I’ll catch y’all next post!



First Post of 2020

Ah, you didn’t think I’d make a January post, did ya now? Well, I did, so let’s get on to the cool part…

Well, I started this in January…

January has been kinda all over the place for me, just like this post will likely be. The celebration of the Invertebrate Club of Southern California’s 1st Anniversary meant I came home with quite a few invertebrates, and then a few collecting trips meant I came home with a few more+a lot of rotting leaves and wood for my detrivorous charges. Unfortunately I seem to be continuing my theme of gaining species only at the loss of something else…

Anywho, let’s start with the new stuff. I traded for one new species of isopod and one new morph, Porcellio scaber “Koi”, a species I seek to redeem myself with, and Porcellionides pruinosus “Powder Orange”.

Porcellio scaber “Koi”. I ended up with about 10 of these awesome little isopods.
One of the reasons I am so happy to have these is that I now have an opportunity to redeem myself. The last P. scaber I kept, the “Orange” morph, got wiped out after a preventable mold outbreak in their enclosure. Ever since I’ve missed having these in my collection…
Side view. From this angle the orange at the head of this particular specimen makes it look similar to an “Oranda” goldfish, ha ha.
Porcellionides pruinosus “Powder Orange”. This variety seems to attain a larger maximum size than the “Powder Blue’s” I have. Only 1 more morph of P. pruinosus to go (“White Out”)!

Continuing with isopods, Some Time Ago, at a Reptile Show Not Far From You…I half-traded/half-bought a starter culture of Armadillidium sp. “Montenegro” (this was before the name klugii was in common use), one of my all-time favorite isopod species. They thrived for a while, but then a mold outbreak in combination with poor feeding resulted in the loss of the entire colony. That is, except for one specimen. It has survived over a year now on it’s own in a tub, and to be completely frank I didn’t think much of it. However, I was discussing invertebrates with a friend when he mentioned he had a colony of A. klugii “Montenegro”. I mentioned I had one specimen left, and that if he liked I could trade/give it to him. He agreed, and soon I went digging through the tub to find the one specimen I had left. However, much to my surprise, I found two specimens! I have no idea how I missed the second one despite the multiple times when I looked through the enclosure. Anyway, I moved them to a smaller 3 ounce deli cup where I could keep an eye on them. I then sexed them a few days later, both turning out to be female, and again to my surprise I found that they both had the distinctive white mancae dots. Now I tore apart the tub they had been in, but no male isopod was to be found. There were a few old exoskeletons of specimens that had died, but I assumed they were from the previous colony crash. Maybe a male survived, impregnated the two females, and then died before I could find it?

However it happened, I’m glad there is still the possibility that these two specimens could restart the colony for me. The saying “Where there’s life there’s hope” holds very true in this instance.

Moving on, we shall leave the isopods in favor of another mystery…

While pulling some stow-away babies from my old Porcellio laevis “Dairy Cow” enclosure, I did a little digging around to see if I had missed any. I certainly hadn’t missed any isopods, but I had missed a millipede!

To lend context to this story, the enclosure I used to keep the P. laevis in had formerly been the enclosure for a 1:1 pair of Acladocricus sp. “Philippine Blue” millipedes. Unfortunately the female I believe died early on, and the male I transferred over to another enclosure. The enclosure sat empty of specimens for a while, although I retained the substrate, until I purchased the P. laevis. Needless to say they didn’t do well, so I moved them to a different enclosure. As stated above, I did find P. laevis babies however in the enclosure a few months later, leading to the discovery of the mystery millipede…

It doesn’t look like an Acladocricus sp. baby, but considering that that was the only millipede species kept in the enclosure, it seems that it has to be. The 1:1 pair never made it to maturity together however…

A true conundrum!

This ends our regularly scheduled “Isopods and Myriapods” segment. Now we turn to our spin-off program, “Insects Among Us”.

As some of you may recall, my Blaberus giganteus weren’t doing so hot (both figuratively and literally) last time we took a look at them. However, I am happy to announce that they have made a comeback! I was able to get some new specimens from a good friend to supplement the remaining three I had, and the night I introduced the new specimens one of those three, which had been looking plump for a while, decided to give birth to a bunch of nymphs!

What’s incredible is that the female gave birth despite the temperatures having been in the mid-to-low 60s (degrees Fahrenheit). A hardy strain or just a lucky break?

I also acquired 10+ Gromphadorhina portentosa of various sizes from the same friend, as her colonies have increased in size immensely. They do seem to be hybrids of some sort, but either way I am very happy to add another roach species to the collection!

During a recent collecting trip I was able to locate three or so Jerusalem Crickets (Stenopelmatus sp.) within 5 feet of each other! I collected one and let the others remain. I have decided to trade it to a friend, but it is still stunning to observe while I have it. Large specimens of this species gain bright orange heads that an enthusiast can see from a mile away.

Now for the bad news. I was excited to share that I had been gifted by a friend a teeny-tiny Ctenidae sp. “Mamfe” spiderling, a species I really wanted. It was literally probably half the size of a small pinhead. It was doing well, eating like a champ, and then one day I found it motionless. It then rapidly desiccated into nothing. I didn’t do anything wrong that I can think of, as their care is pretty straight forward. Perhaps it was just one of those specimens that was meant to perish sooner rather than later…

And that will bring us to the end of this messy almost-January post. I have much more to update y’all on, but that’ll have to wait till the February post…