Eleodes osculans breeding question

 I recently upgraded my desert beetle tank with a male and female and within hours they were mating. I read on bugguide they lay their eggs in dry soil and the larvae eat detritus, so I attempted to recreate this in a corner of the tank with coco fiber, dead leaves and rotting oak. Has anyone ever had success breeding these beetles? If so, am I way off track? Will my other beetles eat the eggs or larvae? Any help would be appreciated. 

 
They are very easy to breed and will pupate readily together if set up properly. Keep them in a very well ventilated tank with at least 3-4 inches of sandy substrate, keep two thirds of the enclosure dry and the other third moist, prefferably with a vertical humidity gradient, but a side to side gradient works too. Make sure they got a lot of hides, toilet paper rolls work well. 

Both adults and larvae love dog food as a staple diet, and they'll snack on dead leaves too. Adults are very messy eaters, so if you ever have grain mite problems just let most of the enclosure dry out for a while, and they should go away. 

They are a very prolific species and quite easy to rear, larvae will dig to the bottom of the enclosure where it's moist and construct pupal cells. If the substrate is deep enough and moist at the bottom, they should pupate communally with few problems. :)  

Dead leaves and wood are not needed for development, but it can't hurt to add them. And no, the mother shouldn't eat the eggs if the enclosure is big enough and the substrate is deep enough. 

Hope this helps! 

 
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I've produced about 100 adults of these guys using the "pupation in situ" method that was introduced to me by Kyle Kandilian. 

I keep them in a 27 qt. enclosure with about 7-8 inches of a 40% sand/60% coconut fiber (give or take) mix, which I keep moderately moist in the bottom 3/4 or so and dry in the upper 1/4 or so. Besides that, I just include a few halfed paper towel rolls on top for the adults to hide under.

 
Yeah this species is especially tolerant of pupating communally, more so than any Eleodes I've bred before.
They're definitely one of the easiest species out there to culture; I'm looking forward to mine reproducing again since I went through the process of curing them from the Trichoderma fungi. :)  

 
Thanks for the replies guys!  Very much appreciated.  I'm setting up a enclosure now to attempt  breeding/rearing. Will Temps of around 75 F be ok? Or should I keep them warmer to encourage breeding? 

 
Thanks again everyone. Enclosure is setup, I'm just waiting on the top layer to dry a little before I put the adults in. Hopefully I can report back with success in the coming months.

 
Glad you were able to beat that terrible fungus, really hope they breed prolifically for you soon! :D
Thanks! I should have said that I went through the curing process that has saved a species in the past, but I'll still be waiting until I see some larvae and/or a stop in the die-off to confirm that it worked for sure. lol

 
Hello fellow E. osculans breeders. I've just set up a breeding enclosure today with a large group of these beetles to try breeding. Could you share a little bit about the fungal pathogen you're referring to, or point me to a few online resources? It's not on my radar and judging by the way you're discussing it, I think maybe it should be? Thanks!Screen Shot 2019-04-11 at 2.58.32 PM.pngScreen Shot 2019-04-11 at 2.58.50 PM.png

 
@davehuth I've been told by a friend who has dabbled in mycology that the harmful fungus that has affected my darklings is a type of Trichoderma fungus. It is supposed to be a very common fungi found in many environments, so it should be able to come in on unsterilized materials from the wild and possibly even coconut fiber (I personally wouldn't worry much about the coconut fiber). I think it might additionally be able to manifest itself in humid environments and on surfaces like leaves that get moistened and dried out repetitively in environments like darkling beetle enclosures and since I have never had a problem with any of my species laying eggs without them, I just avoid them all together. 

If you have a species that has become infected by the aforementioned fungus, you will see odd, premature deaths in mainly the larvae, but also the adults. Once dead, the larvae tend to show the fungus externally if they haven't already been consumed by other larvae/adults at that point and the substrate may also clump around them. I don't usually notice any external signs of the fungus on the adults that have been struck down by it, but perhaps that's because their bodies usually get dismantled very quickly by the other adults. Another thing to mention is that the adults will also stop laying eggs once infected.

The method of curing this fungus (shared with me by the same friend who gave me the I.D for it) is simple, but rather painstaking. The affected individuals must be sprayed/swished around in water to rinse off any spores that may be present of the surface of the beetles' exoskeletons. The individuals are then placed into a sanitary enclosure with a carrot for hydration and a very thin layer of sterilized, bone-dry coconut fiber since their immune systems need all the protection they can get at that point. I'm told a corner of the enclosure can be moistened for the adults to lay eggs in, but I find that at least some species will lay their eggs anyway. For the next two weeks, the carrot must be taken out and replaced every 2 days (or less) to avoid it possibly amassing spores on its surface. After the two week mark has hit, the first step should be repeated and then they can be placed back into a normal set-up. 

 
Thanks so much for this helpful summary. This is certainly something i want to watch for. Since I rarely sterilize substrate and structure materials, my enclosures may be at risk. I'll keep a watchful eye. I wonder if there's a prophylactic method, but probably being more diligent sterilizing materials is the best way. Thanks again.

 
Thanks so much for this helpful summary. This is certainly something i want to watch for. Since I rarely sterilize substrate and structure materials, my enclosures may be at risk. I'll keep a watchful eye. I wonder if there's a prophylactic method, but probably being more diligent sterilizing materials is the best way. Thanks again.
Happy to assist. :)   Yea, I personally advocate for a very sterile environment for all darklings (and many inverts in general); I just don't see going unsterilized as worth the risk.

 
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