Citrus gall midge

Scientific name

Prodiplosis longifila (Diptera: Cecidomyiidae)

Similar species

other midges in the genus Prodiplosis including Prodiplosis myricae, Prodiplosis vaccinii, and Prodiplosis citrulli

Distribution

United States: Florida.

Worldwide: the Caribbean, Colombia, Ecuador, Peru, and South America.

Diagnostic characteristics

Adults

• 1.5 mm (0.06 in.).
• Blackish-yellow body.
• Gnat-like fly.
• Two wings 1.5 - 1.7 mm (0.06 - 0.07 in.).
• Antennae: female - 1.22 mm (0.05 in.), male - 1.62 mm (0.06 in.).

Pupae

• Light yellowish initially, blackish-yellow prior to emergenceemergence:
  used to describe the completion pupation that culminates in the appearance of the adult form of an insect
  .
• 0.85 - 1mm (0.033 - 0.04 in.) in length.
• Cocoons made of whitish spun material often with sand grains incorporated.

Larvae

• Three larval instars. LI>Mature larvae are 1.9 mm (0.071 in.) in length.
• Initially transparent, gradually turn white, yellowish-orange prior to pupation.
• One-segmented, conical antennae.

Eggs

• 0.27mm (0.010 in.).
• Usually deposited on the stamens and styles.
• Clear.

Hosts

Citrus hosts

• lemon, Citrus limon
• Mexican (or Key) lime, Citrus aurantifolia
• pummelo, Citrus maxima
• sweet orange, Citrus sinensis
• Volker's lemon, Citrus volkameriana

Non-citrus hosts

• alfalfa, Medicago sativa
• bean, Phaseolus spp.
• castor bean, Ricinus communis
• Chenopodium ambrosiodes
• pepper, Capsicum chinense
• potato, Solanum tuberosum
• tomato, Solanum lycopersicum
• wild cotton, Gossypium thurberi

Host damage

Flowers

• Larvae are frequently found on the surface of the flower ovary, stamens, and petals.
• Can cause necroticnecrotic:
  the damage caused by cell death (necrosis) in plants or other organisms, often a result of insect feeding on plants, and displayed as brown or black coloration of tissues
  patches on the plant tissue.
• Ovaries may be destroyed.
• Premature flower drop (abscission).

Biology

Adult gallgall:
a distorted area of stem or leaf tissue arising from the plant's response to attack by certain pests and pathogens
midges do not feed and only live for 1 - 2 days. It is the larvae that damage plants. After feeding for 8 - 12 days, the larvae drop to the ground and burrow approximately 1.5 cm (0.6 in) into the soil to pupate.

References

Gagné, R.J. 1986. Revision of Prodiplosis (Diptera: Cecidomyiidae) with description of three new species. Ann. Entomol. Soc. Am. 79: 235-245.

Mamaev, B.M., N.P. Krivosheina, J.H. Wieffering, and J.C. Roskam, (Ed.). 1993. The larvae of the gallgall:
a distorted area of stem or leaf tissue arising from the plant's response to attack by certain pests and pathogens
midges (Diptera: Cecidomyiidae): comparative morphology, biology, keys. CRC Press, Boca Raton, FL.

Peña J.E., R.M. Baranowski, and R.T. McMillan Jr. 1987. Prodiplosis longifilia (Diptera: Cecidomyiidae), a new pest of citrus in Florida. Fla. Entomol. 70: 527-529.

Peña, J.E., R.J. Gagné, and R. Duncan. 1989. Biology and characterization of Prodiplosis longifila (Diptera: Cecidomyiidae) on lime in Florida. Fla. Entomol. 72: 444-450. (http://www.jstor.org/stable/3495182?cookieSet=1).

Peña, J.E. 1994. Update on status of pests of tropical fruit crops in South Florida. Proc. Fla. State Hort. Soc. 107: 340-342. (http://www.fshs.org/Proceedings/Password%20Protected/1994%20Vol.%20107/340-342%20(PENA).pdf).

Peña, J.E., and F.W. Mead. 2007. Featured creatures fact sheet: Citrus gallgall:
a distorted area of stem or leaf tissue arising from the plant's response to attack by certain pests and pathogens
midge, Prodiplosis longifila Gagné (Insecta: Diptera: Cecidomyiidae). Publication EENY-035. University of Florida. (http://edis.ifas.ufl.edu/pdffiles/IN/IN16200.pdf).

Authors

Weeks, J.A., K.W. Martin, A.C. Hodges, and N.C. Leppla