Page Intro: Cybocephalus nipponicus, also known as the “scale picnic beetle,” is used for the control and management of various scale insects. 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
These extremely tiny black or black and orange-tan beetles — the color depends on sex, the males are two-toned — love scale insects. Not just any scale insects, though. They’re not as opportunistic as many beetles. C. nipponicus feed primarily on euonymus scale (Unaspis euonymi), and will also feed on San Jose scale (Quadraspidiotus perniciosus), which is the species on which they are reared in the insectary. Most beetles are very opportunistic and will eat pests other than those assigned to them, but this is a big unknown as it concerns the Scale Picnic Beetle. It is suspected, at least based on lab work, that these beetles will consume other armored scale insects such as the juniper scale (Carulaspis juniperi), pine needle scale (Chionaspis pinifoliae) and others, but these are really unconfirmed. I, therefore, do not recommend using these beetles for other pests without fully acknowledging that this practice would be purely speculative and experimental. And even then, without a lot of replication, coincidental cross-predation should be regarded as a bonus of the application and nothing more.
C. nipponicus are shipped as pre-fed, pre-mated, insectary-reared adults. They are ready to feed on scale insects immediately upon release. However, do not expect fast results when using these critters as it’s not in the cards. There used to be a fast-acting, euonymus scale-eating beetle being commercially produced several years ago, but the insectary handling that project has long since closed its doors. The beetle was Chilocorus kuwanae and it was well-known for its scale-eating abilities. All along, during the reign of C. kuwanae, C. nipponicus could be found at C. kuwanae’s side, munching away slowly, picking up the leftovers. Meanwhile, during the close of one insectary, another opened its doors and began offering C. nipponicus commercially. The new insectary was quite enamored by C. nipponicus’s ability to pick up the leftovers and remains. They noted the feeding behavior was rather slow, but relentlessly effective. I won’t tell you this beetle is great if you need control right away, but if you’re willing to give them a two or more years to do their thing, your patience should be rewarded. [Intro]
Life-style
The all-black 1 mm. adult female beetles lay their eggs in amongst scale insects — 250-300 of them. The eggs hatch into small gray larvae. These, too, are fierce predators, growing up to 1.5-2 mm. long and consuming vast numbers of small scale crawlers and eggs (they’ll always eat the youngest, most tender morsels first). The black and orange-tan males do nothing but eat, drink and mate (this sounds familiar).
Depending on conditions, the life-span of these predators is roughly 30-40 days in their immature stages, then 2-3 months as adults. The conditions for optimum performance will be between 77-81°F with a relative humidity of around 50-60%. But these are optimum conditions, and not necessarily a prerequisite of successful implementation. Please note, however, significantly cooler or warmer temperatures and humidity fluctuations may hamper reproduction and development a certain degree. 50°F is essential for these beetles to remain active. [Intro]
Benefits
These beetles are known for their ability to disperse well within a limited target area. In other words they’ll all scatter upon release but will stay within the general area for which they were intended. They are very methodical and will eventually get the job done. [Intro]
Drawbacks
Scale Picnic Beetles are fairly expensive if you’re really looking at the cost-per-beetle. Moreover, as was already noted, they’re slow to work. However, since this is expected and known at the onset, I’m not sure if this is really a drawback. I guess it is if you’re looking for the control of the target scale insects in a large area and you need control by yesterday. [Intro]
Scouting
Looking for the presence of beetle stages is one way to scout their activity, but this may be difficult for the typical untrained eye of some scouts. Reduction of scale insects — especially the immature stages and eggs — is another way of scouting for results. The problem is that it can take such a long time for very noticeable reductions, that it can appear as if nothing is happening in the short-term. Perhaps scouting once and then doing it again in two years would provide a snapshot of a huge before and after difference.
Look for new growth coming up clean. This may be one sure sign of impending success. [Intro]
Advisories
Give them time. Other than that, if you have the right scales and tolerable conditions (and you don’t panic and spray these predatory beetles to death), putting a few out, in time, will provide results. [Intro]
Usages
Greenhouses, interiorscapes, gardens, nurseries and landscapes. 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 C. nipponicus. [Intro]
