Page Intro: Delphastus cataliniae =pusillus, also called the whitefly destroyer, and it’s an effective predator of various whitefly species. On this page you will find a description, life-cycle info, benefits, drawbacks, scouting info, advisories, usages, and other good stuff such as ordering.
Description
Like Hippodamia convergens, Delphastus cataliniae, are ladybug beetles. Exceptionally small ones, but ladybugs nonetheless. These beetles, with their small, shiny round black bodies, love whiteflies. They can clean up large populations. And, as most beetles are, D. cataliniae are very opportunistic and will eat pests other than whiteflies: spider mites, newly born aphids, insect eggs, etc. I do not recommend using these beetles for other pests, though. We believe control of other pests might not be obtainable with typical predator releases. Coincidental cross-predation should be regarded as a bonus of the application and nothing more. With whiteflies, though, these beetles have proven themselves worthy. Most of my contacts have reported good results with their use. Especially our greenhouse and interiorscape customers. D. cataliniae are shipped as pre-fed, pre-mated, adults. These beetles are shipped with a tiny amount of Biodiet [beetle diet] in their jar, but it is provided merely as a moisture source. These predators eat very little of the stuff, so it is not recommended for supplemental usage at your release site. [Intro]
Some popular prey of these beetles includes: the greenhouse whitefly (Trialeurodes vaporariorum); the sweet potato or tobacco whitefly (Bemisia tabaci); the silverleaf whitefly (B. argentifolii); other Trialeurodes species; the Japanese bayberry whitefly (Parabemisia myricae) as we’ve had the opportunity to see; and more obscure, lesser-known species, including, supposedly, the California giant whitefly (sp. unk.) which we understand is a new threat in the west. [Intro]
Life-style
The tiny 2 mm. adult female beetles lay their eggs in the middle of the “rings” of whitefly eggs — up to 75 of them. Please note: the immature stages of the whitefly, their “scales,” which are found sometimes in great numbers on the undersurfaces of the middle to lower leaves often mistaken for the eggs, which are usually located on the undersurfaces of the upper leaves. The eggs are very, very small (0.2 mm.) are quite difficult to actually see. The eggs hatch into small pale-yellow larvae. These, too, are fierce predators, growing up to 3 mm. long and consuming vast numbers of small, immature stages and whitefly eggs (the larvae, and adults, always eat the youngest, most tender morsels first). [Intro]
The life-span of these predators is roughly 3 weeks in their immature stages, then 4-5 weeks as adults. The conditions for optimum performance will be between 60-90°F with a relative humidity of 75% and up. But these are optimum conditions, and not necessarily a prerequisite of successful implementation. Please note, however, cooler temperatures will hamper reproduction and development a certain degree. [Intro]
Benefits
These beetles have been known to completely devastate a well-established whitefly infestations in a small amount of time. The females demonstrate a keen sense of survival awareness for their young; laying the eggs in the center of whitefly egg-rings assures the young will find food regardless of the direction travelled after hatch, and thus find it easier to survive. The long-term establishment of these predators are possible in outdoor conditions, mostly (see Drawbacks). It’s tough indoors because it is nearly impossible to maintain an adequate food source. The beetles consume the whiteflies necessary for their establishment too quickly (this is probably going to really upset growers, huh?). These predators will consume some pollen and a small amount of honeydew (whitefly poop, yuk!). This will aid their proliferation by a small degree. Searching is the trait which most supports the widespread use of these beetles. They’re excellent at it. This allows the release of fewer beetles without compromising results. Especially in large outdoor applications where the hot-spots these beetles are famous for cleaning up are more spread out. [Intro]
Drawbacks
D. cataliniae, a Florida native, cannot handle harsh winters, even though light frosts are okay. Consequentially, their ability to establish will be negated in northern climes. They can’t handle too much honeydew. Check out the honeydew situation first. It may be necessary to attempt cleaning heavy deposits. Some crops, tomatoes for example, have hairs which tend to impede the progress of the D. cataliniae larvae. This must be taken into consideration when figuring your release rates (see Rates) to compensate for this drawback. [Intro]
Scouting
Look for whitefly “scales” which look like they’ve been partially eaten. Finding the adults or larvae can be fairly exhaustive work, though adults may be seen sometimes on overcast days flying around. Clean new plant growth and natural honeydew reduction may also be apparent scouting indicators. Monitoring whitefly adult numbers with yellow sticky traps may also be a fair indicator. If adult numbers are really high, one strategy I suggest is to use vacuum cleaner to suck them up, can reduce those numbers extremely fast, before predator-one is ever released. [Intro]
Advisories
Aside from misting the site with water before releasing and doing so in the evening (sometimes not necessary in interiors), there are other things you can do to ensure the maximum number of beetles concentrate on the pests at hand. Flowering, pollen producing plants can be a big plus.
Ants, if present, should be controlled. They will defend whiteflies from predators and parasites to protect their honeydew/excrement food, barf! Use barrier products or boric acid products to control the ants. These beetles may be attracted to light colors, so watch your sticky traps, if you’re using them. If you’re catching too many beetles, remove the traps from the site or set them out for only 2-3 days per week. [Intro]
Usages
Greenhouses, interiorscapes, southern orchards, fields and nurseries. Anywhere conditions are right and food is plentiful! [Intro]
Rates, Instructions, and Purchase
Need more information? Check out our release rates or our short-term storage, handling, and release instructions. You may also purchase D. pusillus. [Intro]
