Discoid Roaches vs Dubia Roaches: Which Feeder Wins?
I keep feeder colonies, and the two roaches I get asked to compare more than any other are the discoid (Blaberus discoidalis) and the dubia (Blaptica dubia). They sit so close together that a lot of "which is better" content just picks one, invents a few advantages, and declares a winner. That's not honest. These two are nearly the same animal wearing different legal paperwork, and the right pick comes down to a handful of real differences — not a knockout.
So this is the head-to-head I wish existed: every axis that actually matters, an honest verdict on each, and a clear bottom line. I'll fix the errors that float around the internet on this topic as I go (people swap the two species' scientific names constantly, and the calcium claims are a mess), and I'll tell you straight where it's a genuine tie.
Meet the two contenders
Both are tropical roaches in the family Blaberidae, both native to Central and South America, both decomposers that eat decaying plant matter, and both live-bearers — females carry the egg case (ootheca) internally and give birth to live nymphs rather than leaving an exposed clutch to dry out. That shared biology is why they behave so similarly in a bin and feed so similarly to your animals.
- Discoid roach (Blaberus discoidalis). Broad, oval, glossy, tan-to-brown. Adults reach about two inches. Winged but not capable of sustained flight. Calm but quick to scatter when disturbed.
- Dubia roach (Blaptica dubia). Darker brown to nearly black with a speckled look (the "Guyana spotted roach"). Adults run roughly 1.5–2 inches, females larger and broader than the short-winged males. Notably slow and docile — they tend to sit still when handled.
Get the names right, because the source material on this comparison routinely mislabels them — I've seen "discoid roaches (Blaptica dubia)" printed with a straight face. Discoid is Blaberus discoidalis. Dubia is Blaptica dubia. They are not interchangeable on paper even though they nearly are in practice.
The comparison at a glance
| Axis | Discoid (B. discoidalis) | Dubia (B. dubia) | Edge |
|---|---|---|---|
| Legality | Keepable in FL and other dubia-restricted areas | Restricted in Florida as potential invasive | Discoid |
| Breeding speed | Steady, more measured ramp | Matures/reproduces somewhat faster | Dubia |
| Climbing / containment | Can't scale smooth walls | Can't scale smooth walls | Tie |
| Smell / noise | Nearly odorless, silent | Nearly odorless, silent | Tie |
| Nutrition | ~20–23% protein, ~6–9% fat, ~60–65% moisture, poor Ca:P | Essentially the same | Tie |
| Size | Often a touch larger (~2") | Comparable, sometimes a hair smaller | Slight discoid |
| Behavior | More visible, more active | Burrows, plays dead, hides | Slight discoid |
| Availability / price | Less common, regionally stocked | Ubiquitous, slightly pricier per bug | Mixed |
The honest read of that table: this is a coin flip with a thumb on the scale for whichever factor matters most to you. Below is the case for each verdict.
Legality — discoids win
This is the single most decisive axis, and it's the reason discoids exist as a popular feeder at all. Florida regulates dubia roaches as a potential invasive species — the state's subtropical climate means escapees could plausibly establish a wild breeding population, so the rules treat dubia differently from species considered unlikely to survive outdoors. Discoids are widely accepted as feeders in Florida, which is exactly why so many Florida keepers (myself included, living where I do) run discoid colonies instead.
But "restricted in Florida" is not "the law everywhere," and these lists change. Some states and municipalities have their own rules about which roach species you can keep or ship. Before you order either species, confirm your own state and local regulations rather than trusting a forum post about somebody else's state. A reliable non-commercial starting point is your state agriculture department or land-grant extension service — the University of Florida's entomology and nematology department is a particularly good resource on feeder insects and invasive-species rules.
Verdict: If you're in dubia-restricted territory, this axis ends the debate by itself. Discoids win, and they give up very little to do it.
Breeding speed — dubia win
Both are live-bearers, so neither makes you babysit fragile egg cases. The difference is pace. Dubia mature and reproduce somewhat faster, so a dubia colony ramps to harvest-ready sooner and tends to push out a slightly higher nymph count per cycle. Discoids reproduce steadily and reliably — they're not slow breeders in absolute terms — but they move at a more measured tempo, and a new discoid colony asks for more patience before you can crop it without shrinking the founders.
For both species the same things drive output: a warm zone in the mid-80s to low-90s °F, steady humidity, and a real protein-plus-produce diet. Starve them of heat and both stall.
Verdict: If raw colony speed is your priority and dubia are legal where you live, dubia take it. If you're patient, the gap isn't dramatic.
Climbing and containment — tie
You'll read confident claims that one of these "climbs" and the other doesn't. For smooth vertical walls — glass, smooth plastic bins — neither adult can grip and climb out. A plain bin holds both without a sealed lid or a petroleum-jelly barrier. What you're actually containing, in both species, is the newborn nymphs: pinhead-sized and able to walk through drilled holes or coarse window screen. Cover every vent with fine metal mesh (plastic they can chew through eventually) and both species stay put for good.
Verdict: Dead tie. Anyone selling you a climbing difference between adult discoids and adult dubia is overselling it.
Smell and noise — tie
Both are nearly odorless when kept correctly and completely silent — and that silence and lack of stink is the whole reason serious keepers move off crickets, which reek and chirp all night. A healthy colony of either roach is something you can keep in a closet and forget. If either bin starts to smell, the cause is the same: too wet, overcrowded, or rotting food sitting in it. Fix the husbandry, not the species.
Verdict: Tie, and a big shared win over crickets for both.
Nutrition — tie (and dust both)
Here's where the internet does the most damage, so let me be precise. Nutritionally, discoids and dubia are effectively interchangeable. Both land around:
| Nutrient | Discoid | Dubia |
|---|---|---|
| Protein | ~20–23% | ~20–23% |
| Fat | ~6–9% (moderate) | ~6–9% (moderate) |
| Moisture | ~60–65% | ~60–65% |
| Chitin / digestibility | Low chitin, soft, easy to digest | Low chitin, soft, easy to digest |
| Calcium:phosphorus | Poor — phosphorus-heavy | Poor — phosphorus-heavy |
Treat those as approximate as-fed figures — real values swing with diet, life stage, and source — but the relationship is what matters: these two are siblings on the nutrition chart.
The critical correction: neither roach has a good calcium-to-phosphorus ratio. You will see claims that dubia (or discoids) come in at a healthy 1:3 and protect against metabolic bone disease — that's backwards. A ratio like 1:3 is phosphorus-heavy and bad; the calcium-deficient norm for nearly every feeder insect. Which means you must dust both species with a calcium supplement before feeding, every time the animal's needs call for it. Gut-loading the colony well improves the whole package, but it does not fix the calcium gap. Don't let either roach's "great nutrition" reputation talk you out of the calcium shaker.
Verdict: Tie. Pick on something else — and dust regardless of which you pick.
Size — slight edge to discoids
Both top out around two inches, but discoids often run a touch larger and meatier as adults, while dubia sometimes finish a hair smaller (~1.5–2"). For a big bearded dragon, monitor, or tegu, that marginal size and heft can make discoids a slightly more efficient adult feeder. For smaller animals it's irrelevant — both species come in a full range of nymph sizes, so you simply pick the nymph that fits.
Verdict: Minor edge to discoids for large reptiles; a wash for everyone else.
Behavior — slight edge to discoids (for feeding response)
This is a real, if small, difference. Dubia burrow into substrate, hide under egg flats, and play dead when they hit the enclosure floor — great for the keeper's hands, frustrating for a reptile that hunts by movement. A dubia that flips upside-down and freezes can go uneaten until it's lost in the substrate. Discoids tend to stay more visible and on the move, which triggers a stronger feeding response in motion-oriented hunters — chameleons, many lizards, anything that wants to chase.
The flip side: discoids' liveliness makes them slightly more of a handful to scoop during feeding and cleaning, and dubia's docility makes them the easier animal to handle. So it's a trade — easier on you (dubia) versus more enticing to a picky, movement-driven eater (discoids).
Verdict: Slight feeding-response edge to discoids; slight handling edge to dubia.
Availability and price — mixed
Dubia are the default feeder roach of the hobby, so they're stocked nearly everywhere online and in shops — except, of course, the places that restrict them. That ubiquity is real convenience. They also tend to cost a touch more per insect, partly reputation, partly demand. Discoids are less commonly stocked and you'll more often buy them from specialized breeders or feeder suppliers, but in dubia-restricted regions they're the available legal option, and they're frequently priced competitively or a bit cheaper.
If you want healthy, well-started discoids — sized for seeding a colony or for direct feeding — All Angles Creatures stocks discoid roaches (that's my own feeder store, so I keep the colonies the way I'd want them kept).
Verdict: Dubia win on sheer availability where they're legal; discoids win where they aren't, and roughly tie on price.
The head-to-head, plainly
- Legality: Discoids win — keepable where dubia are restricted (Florida especially). Often the whole ballgame.
- Breeding speed: Dubia win — they mature and ramp somewhat faster.
- Climbing/containment: Tie — neither adult climbs smooth walls; mesh the vents for nymphs either way.
- Smell and noise: Tie — both nearly odorless and silent, both a huge upgrade over crickets.
- Nutrition: Tie — effectively interchangeable, and both need calcium dusting (poor Ca:P on both).
- Size: Slight discoid edge — often a touch larger as adults.
- Behavior: Slight discoid edge for feeding response (dubia burrow and play dead); slight dubia edge for handling.
- Availability/price: Mixed — dubia more available where legal, discoids the legal option elsewhere, price roughly even.
Bottom line — it genuinely depends
I'm not going to pretend one of these is a clear champion, because it isn't.
In areas where dubia are legal, either species is an excellent staple, and they're close enough that you should pick on the practical stuff: availability, price, and breeding speed. On those, the slight edge goes to dubia — they're easier to find and ramp a little faster. If your animal is a picky, movement-driven hunter, discoids' visibility can still tip it the other way.
In dubia-restricted areas — Florida above all — discoids are the obvious choice, and the beautiful part is that they give up almost nothing to make that switch. Same nutrition, same containment, same low odor, comparable size, arguably better feeding response. You lose a little breeding speed and a little shelf availability, and you gain a feeder you can actually keep legally.
Either way, the real win is owning your staple — breeding a clean, quiet, escape-proof roach at home and buying variety feeders as needed. Dust it with calcium, gut-load it well, and your animals won't know the difference between the two.
Want to go deeper on the species I keep? See why discoids are perfect for reptile diets and my full breeder's playbook for keeping discoid roaches alive.