new to keeping predatory beetles - what to feed Calosoma scrutator

[ErinM31]

By fortune I found a Calosoma scrutator yesterday evening. It's a bit smelly, yes, but truly a gorgeous beetle with its copper trim and as others have mentioned, it's underside is psychedelic. I would like to keep it, but only if I don't have to hunt down caterpillars! I did some searching on the forum about predatory beetles and that people have had success feeding their Pasimachus species crickets, even though BugGuide lists them as eating caterpillars and other larva in the wild.

I found several threads offering the "fiery searcher," Calosoma scrutator, for sale, but not instructions on their keeping. Has anyone successful kept, fed, even bred these beetles? And how about Pasimachus? I couldn't find care sheets for either genus, not that those are the best sources but would be a start until I could find better advice here.

The only beetles I've kept before are feeders -- bean beetles and mealworms -- and as I once said, I can hardly take any credit for success in that; it's more like containing an infestation.

Calosoma scrutator

• ErinM31
• Apr 20, 2016
• beetle metallic

I found this stunning beetle outside a Walgreens last night. I would like to keep it, if I can...

 

[Hisserdude]

By fortune I found a Calosoma scrutator yesterday evening. It's a bit smelly, yes, but truly a gorgeous beetle with its copper trim and as others have mentioned, it's underside is psychedelic. I would like to keep it, but only if I don't have to hunt down caterpillars! I did some searching on the forum about predatory beetles and that people have had success feeding their Pasimachus species crickets, even though BugGuide lists them as eating caterpillars and other larva in the wild.

I found several threads offering the "fiery searcher," Calosoma scrutator, for sale, but not instructions on their keeping. Has anyone successful kept, fed, even bred these beetles? And how about Pasimachus? I couldn't find care sheets for either genus, not that those are the best sources but would be a start until I could find better advice here.

The only beetles I've kept before are feeders -- bean beetles and mealworms -- and as I once said, I can hardly take any credit for success in that; it's more like containing an infestation.

Calosoma scrutator

• ErinM31
• Apr 20, 2016
• beetle metallic

I found this stunning beetle outside a Walgreens last night. I would like to keep it, if I can...

Many people have kept Calosoma, and they will eat crickets and other soft bodied invertebrates in captivity, along with some processed animal foods like fish pellets, dog food, etc. They can live for up to two years in captivity, and are pretty hardy. The hard part about keeping ground beetles is breeding them, few have done it successfully. @Elytra and Antenna has bred Calosoma in the past, but the larva were weak and the impetus for oviposition remains unknown.

 

[Hisserdude]

Oh, and Pasimachus are also hardy in captivity and will readily eat anything you put their enclosures. Breeding these is extremely hard, I only know of one person that got his to lay an egg and the resulting larva died for seemingly no reason before it got a chance to mature.

 

[ErinM31]

Good to know! Thank you!
Any recommendations on substrate? Would dry peat, coco fiber, and/or topsoil would work? Or do they prefer some moisture? I'm guessing that most would work for keeping adults and specific requirements would only be for oviposition and larva.

 

[Tenevanica]

Good to know! Thank you!
Any recommendations on substrate? Would dry peat, coco fiber, and/or topsoil would work? Or do they prefer some moisture? I'm guessing that most would work for keeping adults and specific requirements would only be for oviposition and larva.

I use coco peat, but I'm sure Hisserdude has some other substrate concoction that works better.

 

[ErinM31]

Thank you both! Somehow I found the thread on here on Pasimachus larvae (that turned out to be Calosoma scrutator) through Google instead of my search here -- go figure, lol. It looked like they used a sort of moist composite (they started out trying to raisw millipedes... hmm, notice a theme there? Lol) I have half a mind to freeze or bake (or both) some composite of dirt and leaves from the outdoors since they're native. Speaking of which, while searching for millipedes, I come across LOTS of gray grubs... but they're probably not anything interesting, nothing predatory at least, probably one if the numerous scarab/may/june beetles around here.

 

[ErinM31]

I took a look on BugGuide -- wow but Pasimachus larva are ugly! They look like a centipede with too few legs and is very angry about the situation (sorry, but centipedes still give me the creeps). But then I guess it would be more of a surprise if the offspring of this warrior tank were cute, lol.

 

[BobBarley]

I took a look on BugGuide -- wow but Pasimachus larva are ugly! They look like a centipede with too few legs and is very angry about the situation (sorry, but centipedes still give me the creeps). But then I guess it would be more of a surprise if the offspring of this warrior tank were cute, lol.

I just got two Pasmiachus viridans (adults of course) and they are absolutely gorgeous!

 

[Hisserdude]

Good to know! Thank you!
Any recommendations on substrate? Would dry peat, coco fiber, and/or topsoil would work? Or do they prefer some moisture? I'm guessing that most would work for keeping adults and specific requirements would only be for oviposition and larva.

I use coconut fiber for most of my Carabids, but a mix of unfertilized potting soil, coconut fiber and some rotten wood may help to induce egg laying. A layer of dead leaves neber hurts either.

Orin had a clean-up crew of isopods when his laid eggs, so they may help induce the beetles to oviposit.

 

[Hisserdude]

I took a look on BugGuide -- wow but Pasimachus larva are ugly! They look like a centipede with too few legs and is very angry about the situation (sorry, but centipedes still give me the creeps). But then I guess it would be more of a surprise if the offspring of this warrior tank were cute, lol.

Hey, those larva look freaking awesome! Then again, things like that and centipedes don't creep me out.

 

[Sarkhan42]

Just got 3 pasimachus (I believe californicus), and this thread reminded me to ask, how large of an enclosure are these kinds of beetles usually kept in? I've been using pretty deep sub, and they have been readily burrowing often, but wasn't sure what length and width I should be looking at.

Edit: forgot to mention I'm not keeping them communal, not willing to take the risk!

 

[pannaking22]

I've kept various large carabids a couple times and they do just fine on cocofiber with a moisture gradient and a few hides. Toss in something soft for them to much on once or twice a week. I personally keep mine in medium critter keepers or those flip top boxes from Walmart - http://www.walmart.com/ip/44785855?...9556352&wl4=&wl5=pla&wl6=130447929872&veh=sem

Pasimachus, Calosoma, and Carabus can all be kept this way. Hardy little guys and quite entertaining once you get back the defensive chemicals.

 

[Hisserdude]

Here are a few interesting threads about rearing Carabids, especially Calosoma.

http://arachnoboards.com/threads/beetle-larvae-id-anybody.166024/

http://beetleforum.net/forums/index.php?showtopic=663

http://www.roachforum.com/index.php?showtopic=5244

 

[Sarkhan42]

Thoughts on a 60/40 or so soil to sand mixture for the pasimachus? Tried it out and it seems to be working well, it holds tunnel shape quite nicely.

 

[Hisserdude]

Thoughts on a 60/40 or so soil to sand mixture for the pasimachus? Tried it out and it seems to be working well, it holds tunnel shape quite nicely.

Yes that sounds like a good substrate for them, may even induce oviposition.

 

[Sarkhan42]

Yes that sounds like a good substrate for them, may even induce oviposition.

A goal of mine eventually! Someone just has to figure out how to get these guys reproducing, they're way to cool not to get more common in the hobby.

 

[Hisserdude]

A goal of mine eventually! Someone just has to figure out how to get these guys reproducing, they're way to cool not to get more common in the hobby.

I agree, someone needs ro figure out a repeatable method of breeding these in captivity. Getting them to mate is easy, but getting them to lay eggs is pretty hard, and for some reason ground beetle larva are prone to unusual die offs.

 

[ErinM31]

I use coconut fiber for most of my Carabids, but a mix of unfertilized potting soil, coconut fiber and some rotten wood may help to induce egg laying. A layer of dead leaves neber hurts either.

Orin had a clean-up crew of isopods when his laid eggs, so they may help induce the beetles to oviposit.

Good to know! At present, my Calosoma has a gradient from a mix of dry peat, coco fiber and sand to moist peat and sphagnum moss. I put his bark hide on the dry side and he clearly likes the dead leaves as he felt it necessary to extend them out to the feeding dish before retrieving the pre-killed cricket I left for him last night. If I can find another and determine genders, I'll transfer to a larger enclosure with wood and isopods too. I should determine the gender as the Calosoma is one of the few of my non-feline pets to have a name, "His Majesty"

@pannaking22 and @Hisserdude thank you both for the advice and links!

 

[ErinM31]

My Pasimachus (only keeping those temporarily) would probably prefer more substrate to burrow in but a layer of dead oak leaves seems to be satisfactory for now. Unless the cricket I gave it happened to keel over last night, the Pasimachus with sufficient leaf cover hunted it down where as the other was still running around so I gave it more leaves and pre-killed its cricket -- this time, lol. Hey, I see links to YouTube videos saying they take down scorpions and the like so I expect them to take down their own crickets!

 

[Hisserdude]

Good to know! At present, my Calosoma has a gradient from a mix of dry peat, coco fiber and sand to moist peat and sphagnum moss. I put his bark hide on the dry side and he clearly likes the dead leaves as he felt it necessary to extend them out to the feeding dish before retrieving the pre-killed cricket I left for him last night. If I can find another and determine genders, I'll transfer to a larger enclosure with wood and isopods too. I should determine the gender as the Calosoma is one of the few of my non-feline pets to have a name, "His Majesty"

@pannaking22 and @Hisserdude thank you both for the advice and links!

Nice, sounds like a great substrate mix, hopefully you got a pair there! Let us know how they do!

My Pasimachus (only keeping those temporarily) would probably prefer more substrate to burrow in but a layer of dead oak leaves seems to be satisfactory for now. Unless the cricket I gave it happened to keel over last night, the Pasimachus with sufficient leaf cover hunted it down where as the other was still running around so I gave it more leaves and pre-killed its cricket -- this time, lol. Hey, I see links to YouTube videos saying they take down scorpions and the like so I expect them to take down their own crickets!

If you're only keeping them temporarily, then when you want to get rid of them you should sell them. They are in high demand, heck I would buy them from you if I weren't saving up my money for roaches!