Some notes on mold

boina

Lady of the mites
Active Member
Joined
Mar 25, 2015
Messages
2,217
Since the topic has come up a few times recently I thought I'd make a post about some basic facts about mold, specifically slime molds.

Slime molds aren't really molds at all, despite the name. They belong to their own taxon Mycetozoa and besides that the systematics of these strange things is a mess I'm not getting into. If you find something like this in your tarantulas enclosure:

IMG_5755a.jpg
that's a slime mold. (Sorry the pic was taken through the side of the enclosure.) Actually these are the sporangia (spore containing bodies). The vegetative phase may look like this:

IMG_5762a.jpg
A slime mold actually and unbelievably consists of one single cell. It has plenty of cell nuclei, but no cell membranes separating them. It moves around in an amoeboid way, forming pseudopodia all over. Actually I think the tiny dots in the second pic may be the tips of the pseudopodia. It eats about everything it can engulf, but usually bacteria, algae, and rotting plant matter. In your tarantulas enclosure it can easily survive by eating bacteria and microscopic alge in the substrate. It may actually also eat real fungus. In this active phase it does depend on moisture, though. As soon as conditions dry out it will form sporangia (see first pic, but they come in all kinds of shapes). These sporangia can withstand bone dry conditions - they even need them to release the spores. As soon as it gets wet again the spores will hatch and form new tiny slime molds. This way they can even survive in a desert.

What does this mean for your tarantula enclosures? Well, once you have slime molds they are practically impossible to get rid of and slime molds are very common. Drying out? Fine, the slime mold will form sporangia and multiply. Increase ventilation? Oh, your slime mold will love that, it can spread its spores all the better. It doesn't need humidity after all, not like real fungus, so fresh air will not affect it at all. Just a waterdish overflown once in a while will be heaven for a slime mold - use the moisture, grow, eat, form sporangia, done.

From this it should be pretty clear that they are not actually harmful for a tarantula, although it's not impossible that they may try to eat a very small molting sling. Still, I don't want them to take over the enclosures, so I scoup them out once in a while when I can reach them and put a bit of fresh dry substrate in it's place. It's enough to keep them in check.
 

chanda

Arachnoking
Old Timer
Joined
Jun 27, 2010
Messages
2,229
They also seem to like light. I get these from time to time in my enclosures, and they are usually sandwiched between the substrate and the glass - particularly on the side of the tank that faces toward the light source. When they start getting bad, I scoop 'em out - but I know they'll be back. Fortunately, I haven't noticed that they cause any harm.
 

FrDoc

Gen. 1:24-25
Arachnosupporter +
Joined
Jul 18, 2017
Messages
832
Now THIS is the kind of stuff that is tremendously helpful.

Danke
 

Walker253

Arachnobaron
Joined
Jun 12, 2016
Messages
554
Continuous issues like this in moist enclosures really need a good springtail culture.
 

boina

Lady of the mites
Active Member
Joined
Mar 25, 2015
Messages
2,217
Continuous issues like this in moist enclosures really need a good springtail culture.
And what are you going to do in a semi dry enclosure, like overflow water dish, then let dry out? Slime mold will thrive, springtails won't.
 

Walker253

Arachnobaron
Joined
Jun 12, 2016
Messages
554
And what are you going to do in a semi dry enclosure, like overflow water dish, then let dry out? Slime mold will thrive, springtails won't.
When I've gotten that stuff in a dry enclosure, and it happens. I've pulled out the tarantula, taken the enclosure far away from the inside of my house (the back of the back yard) and dumped it. Then I wash out the enclosure with soap and water and put new soil back in.
Usually works. Enclosures that repeat, I go straight coir for a base. Seems to help. This last spring was HORRIBLE
 

awiec

Arachnoprince
Joined
Feb 13, 2014
Messages
1,325
When I've gotten that stuff in a dry enclosure, and it happens. I've pulled out the tarantula, taken the enclosure far away from the inside of my house (the back of the back yard) and dumped it. Then I wash out the enclosure with soap and water and put new soil back in.
Usually works. Enclosures that repeat, I go straight coir for a base. Seems to help. This last spring was HORRIBLE
I've found that it does best on coir, I don't recall seeing it on dirt or even peat moss. Honestly it's why I've stopped using coir altogether as I don't like moving around my potent species more than I have to. In the cages it has shown up in I haven't seen any ill effects for the animal but I like to keep them in somewhat clean cages regardless.
 

Anoplogaster

Arachnodemon
Joined
Jan 15, 2017
Messages
675
Since the topic has come up a few times recently I thought I'd make a post about some basic facts about mold, specifically slime molds.

Slime molds aren't really molds at all, despite the name. They belong to their own taxon Mycetozoa and besides that the systematics of these strange things is a mess I'm not getting into. If you find something like this in your tarantulas enclosure:

View attachment 251707
that's a slime mold. (Sorry the pic was taken through the side of the enclosure.) Actually these are the sporangia (spore containing bodies). The vegetative phase may look like this:

View attachment 251708
A slime mold actually and unbelievably consists of one single cell. It has plenty of cell nuclei, but no cell membranes separating them. It moves around in an amoeboid way, forming pseudopodia all over. Actually I think the tiny dots in the second pic may be the tips of the pseudopodia. It eats about everything it can engulf, but usually bacteria, algae, and rotting plant matter. In your tarantulas enclosure it can easily survive by eating bacteria and microscopic alge in the substrate. It may actually also eat real fungus. In this active phase it does depend on moisture, though. As soon as conditions dry out it will form sporangia (see first pic, but they come in all kinds of shapes). These sporangia can withstand bone dry conditions - they even need them to release the spores. As soon as it gets wet again the spores will hatch and form new tiny slime molds. This way they can even survive in a desert.

What does this mean for your tarantula enclosures? Well, once you have slime molds they are practically impossible to get rid of and slime molds are very common. Drying out? Fine, the slime mold will form sporangia and multiply. Increase ventilation? Oh, your slime mold will love that, it can spread its spores all the better. It doesn't need humidity after all, not like real fungus, so fresh air will not affect it at all. Just a waterdish overflown once in a while will be heaven for a slime mold - use the moisture, grow, eat, form sporangia, done.

From this it should be pretty clear that they are not actually harmful for a tarantula, although it's not impossible that they may try to eat a very small molting sling. Still, I don't want them to take over the enclosures, so I scoup them out once in a while when I can reach them and put a bit of fresh dry substrate in it's place. It's enough to keep them in check.
This is super interesting! I know you mentioned that you didn't want to get into the systematics too much. But I'm curious to know. We present slime molds as an organism under the Amoebozoa lineage in our class. Is Mycetozoa a clade under the Amoebozoa? Because other amoeboids don't produce spores, as far as I know.
 

boina

Lady of the mites
Active Member
Joined
Mar 25, 2015
Messages
2,217
This is super interesting! I know you mentioned that you didn't want to get into the systematics too much. But I'm curious to know. We present slime molds as an organism under the Amoebozoa lineage in our class. Is Mycetozoa a clade under the Amoebozoa? Because other amoeboids don't produce spores, as far as I know.
That's what I meant with mess. Mycetozoa may or may not be a clade under Amoebozoa. It may not even exist as a grouping but instead consist of Myxogastria and two other groups who's names I can't remember right now. Some weird slime mold relatives do not even fit into Amoebozoa at all. If you can figure it all out all the more power to you.

(Btw. I'm actually a just molecular biologist who somehow aquired a degree in microbiology along the way, too)

So, listen to the taxonomists - whichever one you chose ;)
 
Last edited:

miss moxie

Arachnoprince
Joined
Jun 13, 2014
Messages
1,804
No, no. All wrong. The first example is "Fuzzy Ball Mold" characterized by the fact that it is fuzzy and forms the shape of balls. The second example is "Tiny Rice Mold" because it resembles tiny granules of rice.


Informative as always. I've never personally seen these types of mold/not-mold yet. Just the fuzzy white cottony-looking mold. Yes that's the scientific classification.
 
Last edited:

boina

Lady of the mites
Active Member
Joined
Mar 25, 2015
Messages
2,217
Problem is I'm the teacher:bag:

If I'm not clear on stuff, my students are certainly screwed.... lol:bucktooth:
Oooops :bag:, sorry (changed the original post). Well, I wouldn't want to teach this stuff, because as far as I've read taxonomists really don't agree on anything when it comes to slime molds.
 

Anoplogaster

Arachnodemon
Joined
Jan 15, 2017
Messages
675
Oooops :bag:, sorry (changed the original post). Well, I wouldn't want to teach this stuff, because as far as I've read taxonomists really don't agree on anything when it comes to slime molds.
Lol.... I usually just default to the idea that taxonomy is a human invention. "Truth" regarding taxonomy is all based on consensus, and humans have a tough time with consensus;)
 

boina

Lady of the mites
Active Member
Joined
Mar 25, 2015
Messages
2,217
I need to post a correction here: While everything I said about slime molds in the original post is right, the pics I used to illustrate my points are actually NOT slime mold, but the sclerotia of some real fungus. I took the stuff to amicrobiologist specializing in fungi and he explained it to me:

Some (not all) real fungi form hard, compact masses from normal mycelium (sclerotia) if the environment dries out. In that form they are actually able to survive not only drought, but also heat and cold. These sclerotia are really hard to kill and will make new mycelium when they encounter moisture - and unfortunately they look rather similar to slime mold sporangia.

I'm really sorry about this mixup, but knowledge evolves - not only general knowledge, but also my personal knowledge ;).

@Venom1080 , I know you mentioned this a few times, so a special apology to you :sorry:
 

Chris LXXIX

ArachnoGod
Joined
Dec 25, 2014
Messages
5,845
Sorry, I'm just a scientist, I'm not infallible.
Dear colleague (I'm a scientist as well, so I can say this) :kiss: as we know, science is basically the art of exploring always an uncharted territory: sometimes what we are searching is only 1 cm near us, but we can't see that. Happens. People need to understand that :pompous:

#respectthescientists
 

Nightstalker47

Arachnoking
Joined
Jul 2, 2016
Messages
2,613
Dear colleague (I'm a scientist as well, so I can say this) :kiss: as we know, science is basically the art of exploring always an uncharted territory: sometimes what we are searching is only 1 cm near us, but we can't see that. Happens. People need to understand that :pompous:

#respectthescientists
Your a mad scientist if anything. :rolleyes:

I wouldn't fund your research to say the least. I mean that in the nicest way possible, you're nuts man.
 
Top