Rhyzobius lophanthae
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.
Rhyzobius lophanthae
At A Glance
Rhyzobius lophanthae is a specialized, small black ladybird beetle that serves as the premier biological control for Armored Scale. Unlike many other predators that only target the "crawler" stage, Rhyzobius is a powerhouse that feeds on all life stages of scale—including the tough, adult armored shells. If you are struggling with persistent scale on woody stems or tropical leaves, this beetle is your most effective natural solution.
Field Notes — Rhyzobius lophanthae
| Species | Rhyzobius lophanthae |
| Common name | Scale destroyer, scale-eating lady beetle |
| Type | Predatory beetle — Coccinellidae |
| Native to | Australia. Long established in warm regions worldwide |
| Ships as | Adults |
| Sold by | Count |
| Size | 2–3mm. Small, dark, with a reddish-brown head and a fine covering of hairs. Doesn't read as a ladybug |
| Hunts | Armored scale — Diaspididae. Oleander scale, San Jose scale, cycad scale, false oleander scale, euonymus scale, tea scale, and others |
| Eats opportunistically | Soft scale, mealybugs, occasionally other soft-bodied insects. Taken on encounter |
| Won't touch | Aphids, thrips, mites, whitefly, fungus gnats, anything in the soil |
| Target stage | Both. Adults chew through the scale cover to reach the insect beneath; larvae feed on eggs and crawlers under the cover |
| How it works | Adults and larvae both feed. A single adult consumes a substantial number of scale over its lifetime, and larvae develop entirely on scale — so the population compounds if hosts hold out |
| Optimal temp | 70–85°F (21–29°C). Warm-loving, like Montrouzieri — activity drops off below 65°F |
| Humidity | Moderate. No high-RH requirement |
| Light | Needs daylight. Adults fly |
| Egg to adult | Roughly 4–6 weeks depending on temperature |
| Adult lifespan | Several weeks to a few months under good conditions |
| Establishes | Yes, in warm conditions with scale present. Reproduces indoors |
| Deploy | Immediately on arrival. Release directly onto infested plants at the scale |
| Release timing | Evening, onto moist foliage. Repeat in 2–3 weeks if scale pressure holds |
| Refrigerate | No |
| Compatible with | Predatory mites, Stratiolaelaps scimitus, beneficial nematodes, lacewings, Aphidius, Cryptolaemus, springtails, Diglyphus |
| Keep separate from | Broad-spectrum and systemic insecticides. Systemics move into the scale and reach the beetle. Yellow sticky cards catch adults — pull them at release |
| 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.
How long does it take to see results?
Can I use this with Neem Oil?
Will they fly away?
Do the larvae look like the adults?
Is this safe for indoor plants?
Can I use them with Aphytis wasps?
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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