Porcelain roaches are the answer to the objection most people have about keeping cockroaches. They are large, slow, striking to look at, and they spend the first part of their lives looking like nothing much at all before the colour arrives. Two of them are regularly available in the UK, both in the genus Gyna, and they are sold under names confusing enough that people order the wrong one.
Quick answer
Gyna are African porcelain cockroaches, named for the smooth, glazed, ceramic-looking finish on the adult wings. The two in UK collections are the Chrome Cockroach (Gyna caffrorum) and the Centurion Porcelain Cockroach (Gyna centurio). Both reach 25 to 35 mm, both want moderate humidity around 50 to 70%, deep substrate and real airflow, and both take months to develop their colour. Chrome is the more forgiving of the two and the better first choice. Both can fly, which matters more than anything else on this page.
The naming trap
Deal with this first, because it costs people money. Both species are sold as "Chrome" by somebody. The name properly belongs to G. caffrorum, whose young adults carry metallic blue-grey wings, but it gets attached to G. centurio in listings too, and "porcelain roach" is used for either.
The only reliable way to know what you are buying is the binomial. Check for caffrorum or centurio in the listing and ignore the trade name. If a seller gives neither, ask.
One other piece of folklore worth killing: despite an old and discredited synonym, Gyna caffrorum does not make any sound. If you want a roach that hisses, that is Gromphadorhina, and we cover it in our Madagascan hissing cockroach guide.
Chrome Cockroach, Gyna caffrorum
Described by Stål in 1856, from southern Africa, and the most forgiving Gyna in the hobby. It tolerates a wider range of humidity and temperature than its relatives, which is why we suggest it as the first porcelain roach rather than the second.
The appeal is a colour progression rather than a single colour. Nymphs are peppered black and white. Young adults come through with metallic blue-grey "chrome" wings. Mature animals soften to a silvery white. Orange-red legs and body hold steady the whole way through, so there is a consistent thread of colour under a changing wing pattern. Few hobby invertebrates change this much as they grow.
Adults run 30 to 35 mm, females slightly larger than males, with fully developed wings patterned to disappear into leaf litter. Unusually for the genus the nymphs spend reasonable time on the surface rather than burrowing out of sight, so there is something to watch through the long development.
Temperature: 21 to 28°C. It is genuinely forgiving here and will sit through a cooler British winter without complaint. The upper half of that range drives breeding, at the cost of more flight activity.
Centurion Porcelain Cockroach, Gyna centurio
The finish is the whole reason to keep this one. The adult wings are smooth and glazed, splashed with cream, maroon and soft brown, and they catch the light like painted porcelain rather than an insect. It is a medium West African species, 25 to 35 mm as an adult, and a close sibling of the larger, more contrasting Chrome.
The catch is patience. The colour arrives only at the final moult. Younger nymphs are plain and dark, and for months you are keeping something that looks unremarkable on the promise of what it becomes. That is a real consideration if you want a display animal now rather than later.
Temperature: 24 to 28°C. Being West African it wants more warmth than the Chrome, and in a typical UK home that means adding gentle heat rather than relying on the room. A low-wattage mat on a thermostat, fixed to the side of the enclosure rather than underneath, works well and avoids baking the base where nymphs sit.
Care, for both
Humidity
Moderate, around 50 to 70%. Damp rather than soaking, with one area kept more humid than the rest so the animals can pick. This is drier than most people expect from an African invertebrate, and running them too wet is a more common failure than running them too dry.
Note that this is a cockroach and the gradient rules we apply to isopods are not transferable. The 65% detection threshold that governs woodlouse husbandry comes from work on Porcellio scaber and there is no equivalent measurement for Gyna. Treat the range above as practical experience rather than as a physiological figure.
Ventilation
Real airflow, not a token vent. Cross-ventilation through mesh set into two opposing walls moves air through the box rather than letting it sit. Stagnant humid air is what turns a moderately damp enclosure into a mould problem, and porcelain roaches are more sensitive to that than to the humidity figure itself.
Substrate and the long invisible phase
Give them depth. Nymphs burrow, and much of the life cycle happens below the surface where you cannot see it. A base of flake soil, rotten hardwood and leaf litter over several centimetres does two jobs at once: it gives them somewhere to be, and it feeds them.
The consequence is that a new Gyna setup looks empty for a long time. This is normal, and it is the single most common reason people think a colony has failed when it has not. Resist the urge to dig, which destroys burrows and stresses animals that were doing fine.
Feeding
Leaf litter and rotten wood do most of the work. Supplement with dried fruit, fish flake or a prepared invertebrate food a couple of times a week, and remove anything uneaten after a day or two. Protein matters more than people assume for a roach that is building wing structure.
Containment: they fly, and they climb
This is the part to read twice. Adult Gyna both climb smooth surfaces and fly. They are not fast or aggressive about it, and they generally prefer to burrow, but an adult that decides to leave will manage it if the lid is off or the ventilation panel is loose.
Practically: a locking or heavily weighted lid, mesh panels bonded rather than taped, and a band of petroleum jelly around the inside top of the enclosure if you want a second line of defence. Do your enclosure maintenance with the lid mostly on rather than fully off, and do it in a closed room.
Warmth increases flight activity, which is the trade-off in running the top of the temperature range to encourage breeding. If escapes worry you, run cooler and accept slower growth.
Which one should you get?
Start with the Chrome if this is your first porcelain roach. It is more tolerant of both temperature and humidity error, it needs less supplementary heat in a British home, its nymphs are more visible so the wait is less dull, and the colour progression gives you something to watch at every stage.
Choose the Centurion if you have kept something from this group before, you can hold 24 to 28°C reliably, and the glazed cream-and-maroon adult is the specific animal you want. It is the prettier of the two at maturity and the more demanding on the way there.
Or keep both. They pair naturally as a genus display, they want broadly the same setup with a few degrees between them, and having the two side by side is the clearest way to see what "porcelain" actually means.
Browse Chrome Cockroaches and Centurion Porcelain Cockroaches, or see the whole cockroach collection.
Frequently asked questions
Are porcelain cockroaches good beginner roaches? The Chrome is a reasonable first cockroach for someone who has kept invertebrates before. Neither is the easiest roach in the hobby, mostly because of the long colourless nymph phase and the flight risk. If you want the simplest possible start, see our beginner cockroach guide.
Do Gyna cockroaches smell? No, not in a properly ventilated enclosure on a substrate that is damp rather than wet. Smell in a roach tub is a sign of uneaten food, waterlogged substrate or inadequate airflow, and all three are fixable.
How long until they get their colour? Months. Development is slow and the final colour arrives at the last moult, so a group bought as nymphs will look plain through most of the first year. This is the normal experience and not a sign anything is wrong.
Can I keep the two species together? We would not. They are close relatives with similar requirements, which is exactly the situation where you lose track of which animal is which and cannot tell whether a colony is breeding. One species per enclosure.
Will they infest my house if they escape? No. These are tropical and subtropical species that need warmth and humidity to persist, and a British house offers neither in the places an escapee would end up. An escaped adult is a problem to catch, not a problem to eradicate.
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