Mealybug Pest Solution: Cryptolaemus, Leptomastix and other parasitoids

Cryptolaemus Description

CryptolaemusCryptolaemus (Pronounced CRIP-TOE-LEE-MUS) is a black or dark brown ladybird with an orange head and tail, it is about 4mm in length and originally from Australia.

It's larvae are white and look rather like very large mealybugs, up to 1cm in length, with a waxy covering, they are more mobile than mealybug.

Cryptolaemus Life Cycle

Cryptolaemus Life CycleEgg to adult takes about 25 days at 30ºC or 72 days at 18ºC. Females start laying eggs about 5 days after emerging as adults, they lay single eggs into the woolly mealybug egg masses, and lay about 10 eggs a day, they can lay up to 500 eggs in their lifetime, they need a plentiful food supply to maintain egg production and females need to mate with males on a regular basis.

The larvae hatch out as voracious predators of mealybugs. Young larvae and adults prefer the smaller stages of mealybug, whereas the large larvae will eat mealybugs of any size. If mealybug is in short supply, Crytpolaemus may also eat young scale insects.

Cryptolaemus Usage

  • Being a predator, Cryptolaemus prefers quite high levels of mealybug.
  • Cryptolaemus is only suitable for use in a greenhouse or conservatory.
  • Cryptolaemus is a strong flier so if vents and doors are left open near to the treated plants they need to be netted over to prevent the Cryptolaemus from escaping.
  • Cryptolaemus should be released on the day of receipt, preferably in the cooler part of the day.
  • Cryptolaemus need the woolly egg masses of mealybugs in which to lay their eggs. Species that do not produce these may not be controlled. They will not control root mealybug.
  • Cryptolaemus work best in the summer and require a temperature of at least 20ºC (68ºF) for a few hours a day, and good levels of sunlight are required if they are to fly to new plants.
  • Cryptolaemus prefer landing on bushy, leafy plants and may be less effective on climbers and cacti.
  • Like all Defenders biological controls, Cryptolaemus is harmless to children, pets and wildlife.

Leptomastix Description

Leptomastix (Pronounced LEP-TOE-MASS-TICKS) are tiny yellow to black wasps, about 3mm long. They are parasites of the citrus and vine mealybug. Anagyrus, a similar parasitoid is also supplied with Leptomastix.  These target different stages of the mealybug lifecyle but like Leptomasix, only attack these species of Mealybug.

Leptomastix / Anagyrus Life Cycle 

Female adults lay their eggs in nearly  nearly or fully grown mealybugs. The parasitised mealybug becomes swollen and brown in colour, finally becoming "mummified".

The emerging adult Anagyrus or  Leptomastix cuts a small circular hole in one end of the "mummy" from which they emerge.

The life cycle takes about 4 weeks at 20ºC (68ºF) and 2 weeks at 30ºC.


Leptomastix and Anagyrus Usage

  • Leptomastix and Anagyrus can be  used in conjunction with Cryptolaemus.
  • They are only suitable for use in a greenhouse or conservatory.
  • Temperatures above 25ºC (77ºF) are required for some part of the day, along with good levels of sunlight.
  • Leptomastix and Angyrus are better at searching out isolated patches of mealybugs than Cryptolaemus.
  • They cannot be stored and should be used on the day of receipt.
  • Like all Defenders biological controls, they are harmless to children, pets and wildlife.

Biological Mealybug Control Product Details

Defenders supply Cryptolaemus and Leptomastix in tubes, the products are simply released in the area to be treated.

Product Name

Area Treated

Product Code

25 Cryptolaemus Adults

Sufficient to treat an area of at least 5 square metres where several plants species are affected.


10 Cryptolaemus Adults

Sufficient to treat an area of approx. 2-5 square metres where several plant species are affected.


25 Cryptolaemus Larvae

Sufficient to treat an area of at least 5 square metres where several plants species are affected.


10 Cryptolaemus Larvae

To treat an area of about 2 square metres. For large infestations more may be required.


Mealybugs Parasitoid Mix 50

Sufficient to treat an area of at least 5+ square metres where several plants species are affected.


All packs of Cryptolaemus & mealybug parasitoids are sent with full release instructions contained in the document wallet on the package.

Remember! Biological controls are living creatures and can be effected by chemical usage. If you've used any pesticides recently check with us before ordering Cryptolaemus or parasitoids. For heavy infestations of mealybugs or if it is too cold, you can use SB Plant Invigorator, an organic spray. This will target colonies and reduce the population. The beneficials can be released as soon as the SB treated leaves are dry but should NOT be used after their release. SB can also be used to spot treat small outbreaks of mealybug.