North American bean thrips

Scientific name

Caliothrips fasciatus (Thysanoptera: Thripidae)

Other common names

bean thrips, California bean thrips, California citrus thrips

Similar species

other species in the genus Caliothrips

Distribution

United States: Alabama, Arizona, California, Florida, Idaho, Louisiana, Nevada, Texas, South Carolina, and Wyoming.

Worldwide: Mexico.

Native to the United States and Mexico.

Diagnostic characteristics

Adults

• Dark, greyish-black body.
• Legs are banded light and dark.
• Both sexes have four wings with numerous fringes surrounding each wing, folded back over the thoraxthorax:
  one of the three main body segments in an insect, located between the head and abdomen, where the wings and legs of the insect attach
  and abdomenabdomen:
  one of the three body segments in insects; the most posterior segment containing the heart, reproductive organs, and digestive organs
  when at rest.
• Forewings banded, two dark and two light grey bands.
• Antennae have eight segments.

Immatures

• Two larval instars, pre-pupapre-pupa:
  the non-feeding last instar larva of insects that undergo complete metamorphosis
  (3rd instarinstar:
  immature stages (larva or nymph) of insects in between molts
  ), and pupa (4th instarinstar:
  immature stages (larva or nymph) of insects in between molts
  ).
• Mature larvae approximately 1 mm (0.04 in.) in length.
• Yellow to orange body.
• Larvae resemble adults, but wingless.

Eggs

• 0.2 mm (0.008 in.).
• Elongate and banana-shaped.

Hosts

Citrus hosts

sweet orange, Citrus sinensis, navel orange varieties.

Non-citrus hosts

North American bean thrips feed on a wide variety of legumes that include weeds and economically-important crops.

Host damage

Other

North American bean thrips do not actually feed on citrus. They are problematic because they take shelter within the cavities of navel oranges and present a problem when exporting fruits to other countries.

Biology

Eggs are laid singly and inserted into leaf or fruit tissue of beans and other legumes. Thrips feed on the plant during the first and second larval instars and adult stage of the lifecycle. The pre-pupapre-pupa:
the non-feeding last instar larva of insects that undergo complete metamorphosis
and pupa are found in the soil and do not feed. Adults migrate into citrus groves in the fall when their hosts die back or are harvested. The adults take shelter in the navels of navel oranges but do not damage or reproduce on the fruit.

References

Dreistadt, S.H., P.A. Phillips, and C.A. O’Donnell. 2011. Pest notes: Thrips. UC ANR Publication 7429. IPM Education and Publications, University of California Statewide IPM Program. (http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7429.html).

Hoddle, M.S., L.A. Mound, and D. Pena. Thrips of California. CBIT Publishing, Queensland. (http://keys.lucidcentral.org/keys/v3/thrips_of_california/Thrips_of_California.html).

Grafton-Cardwell, E.E., J.G. Morse, N.V. O'Connell, P.A. Phillips, C.E. Kallsen, and D.R. Haviland. 2009. UC IPM Pest Management Guidelines: Citrus. UC ANR Publication 3441. IPM Education and Publications, University of California Statewide IPM Program. (http://www.ipm.ucdavis.edu/PMG/r107304111.html).

Mound, L.A., Z. Hongrui, and Y. Bei. 2011. Caliothrips tongi sp.n. (Thysanoptera, Thripidae) from China, and a dubious record of North American Bean Thrips. Zootaxa 2736: 57-62. (http://www.mapress.com/zootaxa/2011/f/z02736p062f.pdf).

Authors

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