Dalotia coriaria - Rove Beetle
10% off your first 4 orders, then 15% off every order after.
Heads up—this is just an estimate. We only ship when the bugs are happy and ready to travel (Mon–Thurs). If a colony needs a beat to peak, or we're propagating a fresh batch, your order might hold up to a week. Treatment bottles jump the line when you've got an active infestation.
Sizing guide
How our sizes work
Sizes are set by how many plants you are treating — not by how much material is in the container.
Every size on every product page names its own coverage right there in the dropdown, so you never have to come here to find a number. Medium — Up to 25 Plants (2,500 Mites) tells you the tier and the count in one line. This page is for the part the dropdown cannot tell you: how to pick between two of them.
These are rough middles. The ladder runs smallest to largest within each product, so a Medium of one species covers more ground than a Medium of another — a nematode drench and a beetle release are not the same job. The count on the size you are looking at is always the real answer.
Pest pressure moves you up the ladder
Plant count is only half the sum. The other half is how much pest is already there. A closed tent holding fifteen plants with thrips on every growing tip needs a larger release than a bright room holding forty plants with a few gnats — the population you are outnumbering is bigger, and the enclosed space lets it rebound faster.
Coverage figures assume a typical active infestation. Adjust from there:
Under heavy pressure, two releases beat one large one. Take the larger size and plan a second release 7–14 days later, which catches the eggs that had not yet hatched the first time.
A few things work differently
A few products read in square feet rather than plants, because that is how they are applied — the outdoor and area-scale releases. Those are Sc and Hb nematodes, Coleomegilla, and the aphid specialists Ervi, Matricariae, and Aphidoletes. Same ladder, different unit.
Sf nematodes and Triple Blend size by plants and pots, like everything else. They are soil drenches for potted plants, so count your pots rather than your floor.
Slow-release sachets have no size. They are sold by the sachet, and you place one per plant or one per few plants depending on pressure. Sachets are a prevention tool — they hold a population in place before a problem starts. If something is already established, a bottle is the correct answer.
Sizing up is cheaper than sizing twice. Predators need enough prey to establish and enough of themselves to find it. Underdosing is the most common reason a release underperforms, and it usually costs more in the end than the larger size would have. When you are between two sizes, take the larger one.
Still not sure? Tell us what you are growing and what you are seeing, and we will size it for you.
Dalotia coriaria - Rove Beetle
At A Glance
Dalotia coriaria (Greenhouse Rove Beetle) is the "heavy artillery" of biological control. Unlike predatory mites that are confined to the soil surface, Rove Beetles are aggressive, winged hunters that can fly throughout your grow space to locate pest hotspots. These generalist predators are voracious eaters, consuming 10–20 prey items per day. They are essential for larger indoor gardens, greenhouses, and large bioactive enclosures where you need a predator that can patrol the entire area—from the soil level up to the base of the stems.
Field Notes — Dalotia coriaria
| Species | Dalotia coriaria (formerly Atheta coriaria) |
| Common name | Rove beetle |
| Type | Predatory beetle — Staphylinidae |
| Ships as | Adults, sometimes with larvae, in a vermiculite or peat carrier |
| Sold by | Count |
| Size | 3–4mm. Dark brown-black, long and narrow, with short wing covers that leave the abdomen exposed. Curls its tail up when disturbed |
| Hunts | Fungus gnat larvae and pupae, shore fly larvae, thrips pupae in the soil |
| Eats opportunistically | Springtails, root aphids, small soil-dwelling larvae, mites, organic debris. Taken on encounter |
| Won't touch | Anything on foliage — aphids, thrips adults, spider mites, whitefly, mealybugs, scale |
| Where it works | Soil surface and top layer, and the greenhouse floor. Both adults and larvae are predatory and both hunt in the substrate |
| Target stage | Fungus gnat larvae and pupae. Also takes thrips pupae, which is the part most people miss |
| How it works | Actively hunts through the top layer of substrate and across the soil surface. Fast-moving and highly mobile — adults fly and will move between pots on their own |
| Optimal temp | 60–85°F (15–29°C) |
| Humidity | Moist substrate required. Won't work in dry media |
| Egg to adult | Roughly 3 weeks at 70°F |
| Adult lifespan | Several weeks; females lay continuously |
| Establishes | Yes, and readily. This is a colonizer — it builds a standing population in moist substrate and persists |
| Deploy | Immediately on arrival. Sprinkle carrier onto the soil surface, or make breeding stations in a few pots and let them spread |
| Release timing | Evening. Onto moist substrate |
| Refrigerate | No |
| Compatible with | Foliar predatory mites, beneficial nematodes, lacewings, ladybugs, Aphidius, Cryptolaemus, Diglyphus, Trichoderma T-22 |
| Keep separate from | Springtails — rove beetles prey on them. Also competes with and predates Stratiolaelaps scimitus to some degree, though the two are commonly run together in commercial programs |
| Chemical interval | One day after neem oil or insecticidal soap. Never with sulfur, at any dilution |
| Safe around | Pets, children, plants |
Target Pests
Environmental Needs
Selection Guide
How to Use
How They're Shipped
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FAQ
What is your Live Delivery Guarantee?
We guarantee that your beneficial insects will arrive healthy and ready to work. Because we are shipping live organisms, we use packaging and expedited shipping to ensure their safety. In the rare event that your order is compromised during transit, please take a photo of the package and contact us within 24 hours of delivery so we can make it right.
Do they fly? Will they infest my house?
I see "worms" in the bottle. Are those pests?
Are they safe for my reptile or terrarium?
Why do they curl their tails up?
Can I use sticky traps with them?
How long do they live?
Help! I'm overwhelmed
Yeah, it's a lot the first time you're using predatory mites. Please email us at info@fgmnnursery.com and we'll be happy to help!
I don’t see anything moving in my bottle or sachet. Does that mean they’re dead?
Not at all! In fact, go ahead and deploy them.
Predatory mites are microscopic (often less than 0.5mm) and naturally blend into their carrier medium (bran or vermiculite).
- For Bottles: The mites often huddle in the center of the bottle for insulation during transit.
- For Sachets: These are "slow-release" nurseries. The mites stay tucked deep inside the breeding media and emerge one by one over 2–4 weeks. Seeing an "empty-looking" sachet or bottle is not proof of a loss; it is simply how they are packaged for maximum survival.
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