Pyrophorus noctilucus, Ignelater havaniensis & Deilelater spp.

This caresheet is likely also applicable to a number of other Pyrophorini species not mentioned here. 

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Housing:

Adults can be kept in any kind of tank or plastic container, just make sure they aren't very crowded, for the US natives a half a gallon container would be the smallest I'd house a starter group of adults in, whilst a starter group of the much larger Pyrophorus shouldn't be housed in anything less than a gallon. They should be provided with a substrate of crushed rotten hardwood or flake soil (for oviposition), at least couple CMs deep. They will appreciate hardwood bark hides and such to cling to and rest under. The enclosure should be moderately to highly ventilated, and the substrate kept pretty moist at all times.

Small Pyrophorini larvae can be kept in 2 oz deli cups filled with a substrate of somewhat compressed, moist substrate, until they reach almost an inch in length. Deilelater can go through their entire growth cycle in a 2 oz cup and don't need much bigger. 

Ignelater will need something bigger to reach their full length in, 16 oz deli cups would probably be the best final enclosures for those that have outgrown the 2 oz cups, though something slightly smaller could be used as well.

16 oz deli cups will work for Pyrophorus that have outgrown their 2 oz cups, but once they hit 2 inches or so, they should be moved to a 32 oz deli, they like having some vertical space in their container for their tunnels. Then they should be set for the rest of their larval stage and will pupate comfortably in such a container.

While the typically recommended substrate for larvae is crushed rotten hardwood, I've found that once they've molted a few times, moving them to a coconut fiber or sphagnum peat based substrate works just fine, so long as you are diligent in feeding them their protein, (but even then they can go weeks or even months between feedings so long as they are kept moist). Seems like only very young larvae actually need to consume rotten wood, after that they pretty much only eat protein based foods. So for smaller larvae you can put a layer of crushed rotten wood a few millimeters to a centimeter deep at the bottom of their deli cups, with coconut fiber/sphagnum peat layered on top of that. 

Perhaps most importantly, ALL live stages require consistent and high humidity, dryness is the only thing that kills larvae of these beetles easily, and yet it seems to be a fairly common problem that people have, as they tend to forget to feed and water their larvae... While larvae can go quite a while in between feedings, if their substrate is allowed to dry out completely they will die.

Diet:

The peaceful adults feed on fresh fruits like apple and banana, I assume beetle jellies would probably work well for them as well.

The larvae on the other hand, are primarily carnivorous. The younger larvae do eat a little bit of rotten wood though, especially during the first few instars, so they'll need access to moist decomposing wood, but after the first few instars the bulk of their diet should be protein based. Dog/cat kibble works fine for a main diet, as well as live prey like mealworms, and perhaps pre-killed crickets and roaches. It should go without saying that because of their nature, the larvae can be cannibalistic, especially as they get larger, and therefore should be kept separately after they've molted a few times. 

Larvae should be fed every couple days for optimal growth, but can go quite a while in between feedings. Watch out for grain mites and remove any uneaten food a couple days after feeding, mites and dryness are really the only things that can easily overwhelm and kill the larvae of this species, they are very hardy otherwise.
Also, be sure to use very small pieces of dog/cat/fish feed for smaller larvae, if the food piece is big enough small larvae may bore into it when feeding, and you may accidentally throw them out with the food when it comes time to replace it. 

Temperature:

A temperature range from 70-75F° seems work best for all life stages. They can take warmer temps, up to 90F° or so, and while this will make the larvae grow faster, that excessive warmth can also lead to them maturing into rather small adults.
Additionally, a sudden and significant raise in temperature can induce medium to large larvae to pupate even more prematurely, even if the larvae are only half the size they can grow to be, leading to stunted but fully functional adults.

Breeding/Life cycle:

Adult Pyrophorus live for 4-5 months, while Deilelater and Ignelater seem to live 1-3 months on average, depending on the species and temps. Female click beetles lay extremely small eggs that are basically impossible to find. Larvae typically start hatching out after less than month, and are TINY, around 1-2 mm long. 

Generally they should be left alone for at least the first instar before separating them, as they are more fragile when very young and Pyrophorus in particular are usually not very cannibalistic until L3, (all they seem to eat is rotten wood at this stage). Deilelater and Ignelater are more cannibalistic though and you should start separating them once they start reaching L2 IMO, even though their diet still probably largely consists of rotten wood at this point.

After the larvae have molted once or twice (or even more for Pyrophorus) and have grown a few mms, separate them and house them in 2 oz deli cups filled with moist compressed substrate, and upgrade enclosure sizes as they grow, (preferred enclosure sizes and substrates are mentioned above in the housing section). Most larvae usually take about a year or two to complete development under optimal conditions, depending on the species and ambient temps.

After they are fully grown, the larvae will construct a pupation chamber towards the bottom of their enclosure in the same manner as most Tenebrionid larvae, they just push substrate up and away from themselves until a little chamber has been cleared out. Their cells lack the thick saliva/frass reinforced walls that scarab beetles make, so be sure not to dig them up or anything. Leave them alone during this stage, just make sure they don't dry out. The larvae sit in the pupal cell for a week or two, then molt into a pupa, which will then take about month to develop into an adult.

Once the adult ecloses, it will typically take another week or two for it to dig it's way up to the surface, let it do it's thing, no need to try to dig it up by yourself in an attempt to help it, (though it's not particularly harmful to do so, as long as the beetle isn't very freshly teneral). Once it rises to the surface, you may remove it from the deli cup and put it in a breeding enclosure with other adults. Then the cycle begins anew. 😊