Category Archives: Insects, Mites & Earthworms

Entomology: Insects, Mites & Earthworms

Insects, Mites & Earthworms, Thysanoptera

Gynaikothrips uzeli (Zimmermann): Weeping Ficus Thrips

California Pest Rating for
Gynaikothrips uzeli (Zimmermann): Weeping Ficus Thrips
Thysanoptera: Phlaeothripidae
Pest  Rating: B
PEST RATING PROFILE
Initiating Event:

On February 5, 2014 Dr. Gillian Watson confirmed the identification of a sample of thrips collected in Torrance, Los Angeles County as Gynaikothrips uzeli. This is a new state and county record and the species is in need of a pest rating.

History & Status:

Background: Gynaikothrips uzeli is a largely monophagous leaf-gall-forming thrips that feeds and reproduces on Ficus benjamina. The thrips forms galls on new growth1. The thrips has also been found on Ficus obtusa, F. pilosa, F. microcarpa, and Macaranga sp.; however, it is not known to reproduce on these alternative hosts4. The primary pathway for the spread of Gynaikothrips uzeli is likely F. benjamina nursery stock. Many of the records from the southeastern states are on nursery stock and the thrips has been intercepted on nursery stock from Florida eight times.

Worldwide Distribution: Gynaikothrips uzeli is native to Southeast Asia including China and India1. Over the last decade it has been invading North America. The thrips was first reported from North America in Florida in 20031 and has since been found in Mississippi, Alabama, Tennessee, and Louisiana1. It has also recently been reported from Hawaii2, Trinidad2, Costa Rica2, Belize3, Puerto Rico3, and Mexico3.

Official Control: Gynaikothrips uzeli is not known to be under official control in any states or nations5.

California Distribution: Gynaikothrips uzeli has only been officially collected in the cities of Torrance and Carson in Los Angeles County.
California Interceptions: Gynaikothrips uzeli has been intercepted 8 times since 2003 on nursery shipments of Ficus benjamina from Florida.

The risk Gynaikothrips uzeli (Weeping Ficus Thrips) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Ficus benjamina is a common landscape plant in California. Gynaikothrips uzeli is likely able to establish everywhere that these plants are grown. The thrips receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Gynaikothrips uzeli is only known to complete its life cycle on Ficus benjamina. The thrips receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.

3) Pest Dispersal Potential: Thrips are capable of rapid reproduction. Gynaikothrips uzeli has demonstrated its ability to move long distances on nursery stock. The thrips receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Gynaikothrips uzeli may lower the nursery value of Ficus benjamina plants by disfiguring them with its leaf-galls and triggering chemical treatments. The thrips receives a Low (1) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.

5) Environmental Impact: The establishment of Gynaikothrips uzeli in California is expected to trigger additional chemical treatments in the nursery industry. The thrips may also have significant cultural impacts as Ficus benjamina is a common landscape plant. Residents are likely to treat plants, increase pruning4, and replace heavily infested F. benjamina with alternative plants. The thrips receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Gynaikothrips uzeli: Medium (11)

Add up the total score and include it here.

-Low = 5-8 points
-Medium = 9-12 points
-High = 13-15 points

6) Post Entry Distribution and Survey Information: Gynaikothrips uzeli is only known from the cities of Torrance and Carson in Los Angeles County. The thrips receives a Low (-1) in this category.

Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.

– Not established (0) Pest never detected in California, or known only from incursions.
– Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
– Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
– High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (10)

Uncertainty:

Significant pests that are not widespread in California have been observed inside the galls produced by Gynaikothrips uzeli. For example, pink hibiscus mealybug (Maconellicoccus hirsutus) has been found living hidden inside these galls1. It is possible that high risk exotic invasive species could travel into and spread within California inside the galls formed by G. uzeli.

There have been no surveys for Gynaikothrips uzeli within California, so it could be more widely distributed.

Conclusion and Rating Justification:

Although impacts of Gynaikothrips uzeli are expected to be limited to Ficus benjamina, this is a common landscape plant in California. Chemical treatments of hosts and changes to cultural practices as residents adapt to this pest are expected to have significant environmental impacts. Furthermore, there is the possibility that other invasive species may spread into and within California inside the galls produced by the thrips. A B-rating is justified.

References:

1Held, D.W., D. Boyd, T. Lockley, G.B. Edwards. 2005. Gynaikothrips uzeli (Thysanoptera: Phlaeothripidae) in the southeastern United States: Distribution and review of biology. Florida Entomologist 88(4): 538-540. http://www.fcla.edu/FlaEnt/fe88p538.pdf

2Held, D.W. and D.W. Boyd, Jr. 2007. Evaluation of sticky traps and insecticides to prevent gall induction by Gynaikothrips uzeli Zimmerman (Thysanoptera: Phlaeothripidae) on Ficus benjamina. Pest Management Science. 64(2): 133-140. http://www.ncbi.nlm.nih.gov/pubmed/18069654

3Cambero-Campos, Jhonathan, Rita Valenzuela-García, Carlos Carvajal-Cazola, Claudio Rios-Velasco, and Oswaldo García-Martínez. 2010. New records for Mexico: Gynaikothrips uzeli, Androthrips ramachandrai (Thysanoptera: Phlaeothripidae) and Montanadoniola confusa (Hemiptera: Anthocoridae). Florida Entomologist 93(3): 470-472. http://www.bioone.org/doi/full/10.1653/024.093.0328

4 University of Florida Extension http://trec.ifas.ufl.edu/mannion/pdfs/WeepingFigThrips.pdf

5 USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 ‘N’ Street, Room 221, Sacramento CA 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov

 Pest Rating: B

Posted by ls

Coleoptera, Insects, Mites & Earthworms

Pagiocerus frontalis (Fabricius): A Scolytid Weevil

California Pest Rating for
Pagiocerus frontalis (Fabricius): A Scolytid Weevil
Coleoptera: Cucurlionidae
Pest Rating: B
PEST RATING PROFILE
Initiating Event:

On May 21, 2014 Dr. Andrew Cline identified a beetle collected in Escondido, San Diego County, as Pagiocerus frontalis (PDR SJ0P06003026). This beetle was also reported from San Diego County in 2010. The beetle presently has a temporary rating of Q, so Dr. Kevin Hoffman recommended a pest rating proposal to determine future direction.

History & Status:

Background: Pagiocerus frontalis feeds and reproduces on the seeds of fallen avocado fruit and both fresh and dry corn. The species is considered a major pest of stored corn in the highlands of the Andes1,2. Beetles infest corn cobs in the field before harvest and continue feeding in storage, destroying the corn within several months1. The beetles have also been found on several other plants including coffee; however, a laboratory experiment found that these other plants were not suitable hosts for reproduction and development1. Pagiocerus frontalis is not known to have ever been intercepted, but could presumably spread long distances when infested fresh or dry corn or ripe, damaged avocados are moved.

Worldwide Distribution: Pagiocerus frontalis is a Neotropical beetle whose range extends from South America, through Central America and Mexico, into the southeastern United States.

Official Control: Pagiocerus frontalis is listed as a quarantine pest by Japan4 and New Zealand5.

California Distribution: In California Pagiocerus frontalis has only been found in San Diego County.

California Interceptions: Pagiocerus frontalis has never been intercepted in any regulatory situations in California.

The risk Pagiocerus frontalis would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Pagiocerus frontalis has a widespread distribution across a wide variety of climates from the Andes in South America to North Carolina. It can be expected to establish wherever it can find suitable host material in California. The beetle receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Pagiocerus frontalis is only known to be able to complete its reproductive cycle on corn and the seeds of fallen avocados. It receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.

3) Pest Dispersal Potential: Pagiocerus frontalis has high reproductive potential; females lay many eggs and it can complete its entire life cycle in 3 to 4 weeks1. The beetles may theoretically disperse long distances through the movement of infested corn or inside the seeds of ripe, damaged avocados. The beetle receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: The value of corn produced in California was approximately $812.1 million in 2012. This includes $234.7 for grain, $454.4 for silage, and $123 million for sweet. Pagiocerus frontalis might increase production costs in these crops, especially organic sweet corn. The beetle is considered a quarantine pest by some nations. The beetle therefore has the potential to disrupt markets by contaminating corn or as a hitchhiker on other commodities. Pagiocerus frontalis receives a Medium (2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Pagiocerus frontalis is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. The beetle is not likely to directly affect threatened or endangered species or disrupt critical habitats. Large populations of the beetle might trigger new chemical treatments in corn when the crop is in the field or storage. Pagiocerus frontalis is not expected to significantly impact cultural practices, home/urban gardening, or ornamental plantings. The beetle receives a Medium (2) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Pagiocerus frontalis: Medium(11)

Add up the total score and include it here.

– Low = 5-8 points
– Medium = 9-12 points
– High = 13-15 points

6) Post Entry Distribution and Survey Information: In California, Pagiocerus frontalis is only known to be established in San Diego County. The beetle receives a Low (-1) in this category.

Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.

– Not established (0) Pest never detected in California, or known only from incursions.
– Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
– Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
– High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (10)

Uncertainty:

There are a wide variety of pests that feed on both fresh and dry corn. It is possible that existing treatments, cultural practices, and modified genes will preclude any economic damage from this pest in California.  Pagiocerus frontalis also feeds on the seed of fallen avocado. These avocados are not likely to be distributed commercially; nevertheless, the presence of this beetle might disrupt markets.

Conclusion and Rating Justification:

Pagiocerus frontalis is only known from San Diego County and has the potential to have limited economic and environmental impacts. A “B” rating is justified.

References:

1 Eidt-Wendt, J. and F.A. Schulz. Studies on the biology and ecology of Pagiocerus frontalis (Fabricius) (Coleoptera: Scolytidae) infesting stored maize in Ecuador. Technical University Berlin, Department of Phytomedicine, Berlin, FRG. http://spiru.cgahr.ksu.edu/proj/iwcspp/pdf2/5/61.pdf

2 Gianoli, E., I. Ramos, A. Alfaro-Tapia, Y. Valdéz, E.R. Echegaray, and E. Yábar. 2006. Benefits of a maize-bean-weeds mixed cropping system in Urubamba Valley, Peruvian Andes. International Journal of Pest Management. 52(4):283-289. http://www2.udec.cl/~egianoli/06gianintjpestman.pdf

4https://www.ippc.int/sites/default/files/documents/20130423/1309849796_qp_list_2013042321%3A18En.pdf

5 http://piorin.gov.pl/cms/upload/seed.pdf

Responsible Party:

Jason Leathers, 1220 ‘N’ Street, Room 221, Sacramento CA 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov

 Pest Rating: B

Posted by ls

Diptera, Insects, Mites & Earthworms

Horidiplosis ficifolii Harris: An Ornamental Fig Pest

California Pest Rating for
Horidiplosis ficifolii: an ornamental fig pest
Horidiplosis ficifolii: an Ornamental Fig Pest
Image Citation: Jakub Beránek
Horidiplosis ficifolii Harris: An Ornamental Fig Pest
Diptera: Cecidomyiidae
Pest Rating: B
PEST RATING PROFILE
Initiating Event:

On November 14, 2014, Dr. Martin Hauser identified Horidiplosis ficifolii on ornamental shrubs in San Diego (PDR 370P06228129). This is the first time this pest has been found in California. A pest rating proposal is needed.

History & Status:

Background: Horidiplosis ficifolii is a gall midge that forms galls on the leaves of ornamental Ficus spp1. Known hosts include Ficus microcarpa1,2, F. retusa2, F. nitida2, and F. panda2. The gall midge may spread long distances when infested host plants are moved.

Worldwide Distribution: Horidiplosis ficifolii is native to China, Taiwan, and Japan. From there it has spread to Florida and greenhouses in Europe.

Official Control: Horidiplosis ficifolii is not known to be under official control in any other states or nations3.

California Distribution: Horidiplosis ficifolii has only been found in San Diego.

California Interceptions: Horidiplosis ficifolii has never been intercepted in regulatory situations in California.

The risk Horidiplosis ficifolii would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Ficus plants are commonly grown in California and Horidiplosis ficifolii is likely to establish where they are grown. The gall midge receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Horidiplosis ficifolii is only known to feed on four species of plants in the genus Ficus. It receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.

3) Pest Dispersal Potential: Gall midges can produce many offspring and may move long distances through commerce in infested host plants. They may also be dispersed locally by wind. Horidiplosis ficifolii receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Horidiplosis ficifolii may increase the production cost of Ficus spp. nursery stock and lower the value of infested plants. It is not expected to lower crop yield, trigger lost markets, change cultural practices, vector pestiferous organisms, injure animals, or interfere with water supplies. The gall midge receives a Low (1) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Horidiplosis ficifolii is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. The gall midge is not expected to affect threatened or endangered species or disrupt critical habitats. The gall midge may trigger new treatment programs in the nursery industry and by residents who find infested plants unsightly. Ficus spp. are commonly grown as ornamentals in California and may be significantly affected by this insect.  Horidiplosis ficifolii receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Horidiplosis ficifolii: Medium (11)

Add up the total score and include it here.

– Low = 5-8 points
– Medium = 9-12 points
– High = 13-15 points

6) Post Entry Distribution and Survey Information: Horidiplosis ficifolii is only known from an incursion into San Diego. It receives a Not established (0) in this category.

Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.

– Not established (0) Pest never detected in California, or known only from incursions.
– Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
– Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
– High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (11)

Uncertainty:

There have been no formal surveys for Horidiplosis ficifolii in California. It is possible that the gall midge may be more widespread. However, the species is relatively new to science, it was just described in 2003. It is possible that it may emerge as a more serious pest as it expands its range.

Conclusion and Rating Justification:

Due to its narrow host range the entry of Horidiplosis ficifolii is expected to have limited economic consequences. However, it may have significant environmental impacts by triggering new chemical treatments in the nursery industry and by residents who find infested ornamental plants unsightly. A “B” rating is justified.

References:

1Steck, Gary J. and Scott Krueger. An Ornamental Fig Pest, Horidiplosis ficifolii Harris (Diptera: Cecidomyiidae), Genus and Species New to Florida and North America. Florida Department of Agriculture and Consumer Services. http://www.freshfromflorida.com/Divisions-Offices/Plant-Industry/Plant-Industry-Publications/Pest-Alerts/Pest-Alerts-An-Ornamental-Fig-Pest-Horidiplosis-Ficifolii-Harris-Diptera-Cecidomyiidae

2Beránek, Jakub and Ivana Šafránková. 2010. First record of Horidiplosis ficifolii Harris 2003 (Diptera: Cecidomyiidae) in the Czech Republic. Plant Protect. Sci. 46(4): 185-187. http://www.agriculturejournals.cz/publicFiles/31854.pdf

3USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 ‘N’ Street, Room 221, Sacramento CA 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov

 Pest Rating: B

Posted by ls