Florida flower thrips

Scientific name

Frankliniella bispinosa (Thysanoptera: Thripidae)

Similar species

Frankliniella cephalica

flower thrips, Frankliniella tritici

western flower thrips, Frankliniella occidentalis

Distribution

United States: Alabama, Florida, and Georgia.

Worldwide: Bahamas, Bermuda, Columbia, Japan, Mexico, Taiwan, and Trinidad.

Diagnostic characteristics

Adults

• 1.1 mm (0.043 in.) in length.
• Yellow with brown hairs (setae) and yellow legs.
• Four, narrow, feathery wings with comb-like edges surrounding the entire margins.
• Eight-segmented antennae, with a pair of stout setae on the second segment.
• Elongate body with a headhead:
  one of the three main body segments in insects; the anterior-most segment containing the many sensory structures including the eyes, antennae, and mouthparts
  wider than its length.
• Thorax thorax:
  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
  (pronotum) has five pairs of hairs (setae) in all species in the genus Frankliniella.
• Florida flower thrips have two setae (group II) on the front corners (antero-angular) of the pronotumpronotum:
  the dorsal surface of the first thoracic segment
  and a second group of setae (group I) on the front edge, approximately one half of the distance between the corner and middle (median) front edge (antero-marginal) of the pronotumpronotum:
  the dorsal surface of the first thoracic segment
  . Group I setae are distinctly shorter than group II setae.
• Western flower thrips can be separated from Florida flower thrips since group I and group II setae are approximately equal in length.

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
  ), pupa (4th instarinstar:
  immature stages (larva or nymph) of insects in between molts
  ).
• Lemon yellow.
• Elongate shape, resembles the adults but with no wings.

Eggs

• Pale yellow.
• Cylindrical, with a slight kidney-shaped curvature.

Hosts

Citrus hosts

All Citrus species and their hybrids.

Non-citrus hosts

Known to infest 29 families of plants including those listed below.

• bean, Phaseolus spp.
• corn, Zea mays
• cucumber, Cucumis sativus
• oak, Quercus spp.
• pine, Pinus spp.
• pigweed, Amaranth spp.
• Rosa spp., particularly white-flowered varieties
• Spanish needle, Bidens alba
• squash, Cucurbita spp.
• strawberry, Fragraria spp.
• tomato, Solanum lycopersicum
• watermelon, Citrullus lanatus

Host damage

Flowers

• Young citrus flowers and buds can be damaged.
• Feed on the petals, pistils, and stamens of the flowers.
• Damaged parts turn brownish-yellow.
• Navel and valencia oranges may experience premature flower drop.

Fruits

• Young citrus fruit can be damaged, causing premature drop.
• Cosmetic scarring of fruit tissue encircling the stem can indicate feeding by thrips.

Biology

The insect feeds on the plant during the first and second larval instars and adult stage of its life cycle. 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. During the summer in southeast Florida, flower thrips can attain maturity in 11 days and have 12 - 15 generations per year.

Comments

There are more than 160 species listed in the genus Frankliniella which can make correct identification difficult and require microscopic examination. For example, Florida flower thrips, Frankliniella bispinosa can only be differentiated from the Caribbean species, F. cephalica visually by the shape of the pedicelpedicel:
from the base, the second segment of the antenna, located between the scape and the flagellum
of the third antennal segment.

Florida flower thrips are able to vector a damaging plant pathogen, Tomato spotted wilt virus (TSWV), a Tospovirus capable of infecting many economically important crops, including citrus, blueberries, strawberries, avocados, vegetables, and ornamentals.

References

Childers, C.C. 1999. Flower thrips: Frankliniella bispinosa (Morgan), F. kelliae Sakimura (Thysanoptera: Thripidae) and postbloom fruit drop disease are economic pests on Florida citrus. Proc. Fla. State Hort. Soc. 112: 88-95.

Childers C.C., and S. Nakahara. 2006. Thysanoptera (thrips) within citrus orchards in Florida: species distribution, relative and seasonal abundance within trees, and species on vines and ground cover plants. J. Insect Sci. 6: 1-19. (http://insectscience.org/6.45/).

Hoddle, M.S., L.A. Mound, and D. Paris. 2008. Thrips of California. Frankliniella cephalica. (http://keys.lucidcentral.org/keys/v3/thrips_of_california/data/key/thysanoptera/Media/Html/browse_species/Frankliniella_cephalica.htm).

Mound, L.A. 2006. Florida flower thrips (Frankliniella bispinosa). Pest and Diseases Image Library (http://www.padil.gov.au).

(OEPP/EPPO) European and Mediterranean Plant Protection Organization. 2002. Diagnostic protocols for regulated pests. Bulletin OEPP/EPPO 32: 281-292 (http://www.eppo.org/QUARANTINE/insects/Frankliniella_occidentalis/FRANOC_protocol.pdf).

Osborne, L.S., and L.O. Durant. 1994. Flower thrips, pp. 1-108. In J.R. Baker (Ed.) Insect and related pests of flowers and foliage plants some important, common, and potential pests in the southeastern United States. (http://ipm.ncsu.edu/AG136/thrips5.html).

Watson, J.R. 1923. The proper name and distribution of the Florida flower thrips. Fla. Entomol. 7: 9-11. (http://www.jstor.org/stable/3492861?seq=2).

Whitfield, A.E., D.E. Ullman, and T.L., German. 2005. Tospovirus-thrips interactions. Annu. Rev. Phytopathol. 43: 459-89.

Yolanda, Y., J. Stavinsky, S. Hague, J. Funderburk, S. Reitz, and T. Momol. 2006. Evaluation of Frankliniella bispinosa (Thysanoptera: Thripidae) as a vector of the Tomato spotted wilt virus in pepper. Florida Entomologist. 89: 204-207. (http://www.bioone.org/doi/pdf/10.1653/0015-4040%282006%2989%5B204%3AEOFBTT%5D2.0.CO%3B2).

Authors

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