Pink hibiscus mealybug

Scientific name

Maconellicoccus hirsutus (Hemiptera: Pseudococcidae)

Other common names

hibiscus mealybug, pink mealybug, grape mealybug

Similar species

other mealybugs (Hemiptera: Pseudococcidae)

Distribution

United States: Florida, Hawaii, North Carolina, South Carolina, Louisiana, and Texas.

Worldwide: Africa, Asia, Australia, the Caribbean, the Middle East, the Pacific Islands, Papua New Guinea, and South America.

Native to Asia.

Diagnostic characteristics

Adults

• 3 mm (0.12 in.) in length.
• Elongate, oval, and soft-bodied.
• Females are greyish-pink, covered in a waxy secretion.
• Adult males are smaller than females.
• Males are reddish brown with one pair of wings. Males have two long waxy filaments.
• When crushed, body fluids are pink.

Immatures

• First instarinstar:
  immature stages (larva or nymph) of insects in between molts
  nymphs are mobilemobile:
  able to move
  and called "crawler crawler:
  the mobile first instar of many scale species
  s."
• Females have three nymphal instars.
• Males have two nymphal instars before going through a pre-pupal and pupal stage.

Eggs

• Freshly laid eggs are orange but turn pink before hatching.
• Eggs are deposited in egg sacs.

Hosts

Citrus hosts

All Citrus species and their hybrids.

Non-citrus hosts

Very wide host rangehost range:
the range of species that a particular organism can feed on to achieve successful growth and reproduction
. In addition to forest and ornamental species, agricultural crops are widely used as host plants. A partial list includes:

• all cruciferous vegetables, Brassica oleracea
• avocado, Persea americana
• bean, Phaseolus vulgaris
• carambola, Averrhoa carambola
• fig, Ficus spp.
• guava, Psidium guajava
• grape, Vitis spp.
• Hibiscus spp.
• lettuce, Lactuca sativa
• mango, Mangifera indica
• mulberry, Morus spp.
• peanut, Arachis hypogaea
• pepper, Capsicum spp.
• squash, Cucurbitaspp.
• sugarcane, Saccharumspp.
• tomato, Solanum lycopersicum

Host damage

Flowers

• Buds may not open to produce flowers.
• Buds may shrivel and die.

Fruits

• May be small and deformed.
• Often covered in white waxy coating.
• Honeydew honeydew:
  the sugar-rich waste product excreted by aphids, mealybugs, and scales insects as a result of feeding on the phloem of plants
  excreted by mealybugs coats the outside of fruits and leaves, and promotes the growth of sooty mold fungus that inhibits photosynthesis, weakens the plant, and makes fruit unattractive.

Leaves

• Feeds on the soft tissues.
• Often covered in white waxy coating.
• Injects toxic saliva that causes curling and contortion of leaves.
• Bunched or unopened leaves.

Twigs

• The entire plant may be stunted, and the shoot tips develop a bushy appearance.
• Growth points stunted and swollen.
• Can become twisted.

Biology

Eggs are deposited in egg sacs in bark crevices, leaf scars, soil, or other protected areas. Eggs may overwinter before hatching in the spring. Eggs hatch into mobilemobile:
able to move
first instarinstar:
immature stages (larva or nymph) of insects in between molts
nymphs, known as crawlers. Immaturesimmatures:
term used to describe the sub-adult stages of insects that do not undergo complete metamorphosis; see also nymph
and adults pierce soft tissues of the plant to feed on the phloem. The saliva that the mealybug injects into the plant is toxic and causes leaf distortion. Populations of mealybugs are often ant-tended.

Females deposit up to 600 eggs and die shortly thereafter. The pink hibiscus mealybug has been reported to reproduce asexually (parthenogenesis) in Egypt.

Comments

All phloem-feeding, honeydew-producing insect pests have the potential to be tended by ants. The ants feed on the honeydewhoneydew:
the sugar-rich waste product excreted by aphids, mealybugs, and scales insects as a result of feeding on the phloem of plants
excreted by the pest and protect the pest from natural enemies. This protection can disrupt biological control programs.

Parasitoid wasps are very effective at controlling populations of pink hibiscus mealybug.

References

(APHIS/PPQ) Animal and Plant Health Inspection Service/Plant Protection and Quarantine. 2012. Pink hibiscus mealybug. (http://www.aphis.usda.gov/plant_health/plant_pest_info/phmb/index.shtml).

(EPPO) European and Mediterranean Plant Protection Organization. 2005. Data sheets on quarantine pests: Maconellicoccus hirsutus. OEPP/EPPO Bulletin 35: 413–415. (http://www.eppo.org/QUARANTINE/insects/Maconellicoccus_hirsutus/DS_Maconellicoccus_hirsutus.pdf).

Hoy, M.A., A. Hamon, and R. Nguyen. 2006. Featured creatures: pink hibiscus mealybug, Maconnellicoccus hirsutus (Green) (Insecta: Hemiptera: Pseudococcidae). Publication EENY-29. University of Florida. (http://entnemdept.ufl.edu/creatures/orn/mealybug/mealybug.htm).

Authors

Weeks, J.A., A.C.Hodges, N.C. Leppla