Tag Archives: Thysanoptera: Thripidae

Insects, Mites & Earthworms

Rose Thrips | Thrips fuscipennis

March 10, 2017 Raj Randhawa

California Pest Rating for

***Thrips fuscipennis*: Rose Thrips**

Thysanoptera: Thripidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

In November 13, 2016, five thrips were intercepted at Needles inspection station from a truck coming from New Jersey heading to Los Angeles on a load of kiwi (Shipment size: 40,000 lbs) originating from Italy and were identified as Thrips fuscipennis. Previously, this species had been intercepted twice in 2012 through CDFA border stations and high risk pest exclusion inspections. A temporary rating of “Q” has been assigned. This pest rating proposal was prepared to determine a permanent pest rating.

History & Status:

Background: Thripini is the most phylogenetically diverse tribe in the family Thripidae, and Thrips is a highly evolved genus in subfamily Thripinae. Thrips fuscipennis is one of the commonly intercepted thrips in at U.S. ports of entry from Africa, Europe, and the Mediterranean. It is a polyphagous species characterized by the presence of ctenidia on abdominal tergites (4). The body length is 1.2-1.4mm, antennae are seven segmented and head is broader relative to most other thrips (5). Life stages consist of an egg, a first and a second larval stage, the propupal and pupal stage, and the adult stage. Reproduction is sexual or parthenogenetic. Eggs are laid in slits cut with the ovipositor into the host plant. Fertilized eggs produce females and unfertilized eggs produce males. One generation is completed in about one month. Thrips overwinter normally as a second stage larva or an adult female in bark crevices or plant debris (4). Hosts plants that Thrips fuscipennis can damage include roses, strawberries, bell pepper and white clover (3). Adult thrips are poor fliers but their feathery wings allow them to be readily carried by winds (6).

Worldwide Distribution: Thrips fuscipennis is native to England and present in Europe. It is currently distributed in Asia: China; Europe: Albania, Austria, Czech Republic, Denmark, England, Estonia, Finland, France, Germany, Hungary, Ireland, Italy, Lithuania, Netherlands, Poland, Romania, Russia, Sardinia, Scotland, Serbia, Slovakia, Sweden, Switzerland, Trancaucasia, Turkey, Wales, and the former Yugoslavia. North America Canada (British Columbia, Quebec) (5).

US Distribution: The first record of Thrips fuscipennis in North America was made by Hood based on his identification of a female collected in Ithaca, New York in July, 1926, on Angelica atropurpurea. This was later identified as Thrips fallaciosus. The first verified record of Thrips fuscipennis was reported from North America by Chaisson in 1986 in British Columbia. The various records of this species from Canada and the United States were misidentification of Thrips fallaciosus, which is widely distributed from Alaska and Labrador south to Utah, Colorado, Iowa, Illinois, and New York but has not been recorded from California to date(4).

Official Control: Thrips fuscipennis is listed as harmful organism by Costa Rica, Japan, Republic of Korea and Taiwan (9).

California Distribution: Thrips fuscipennis has never been found in the environment of California.

California Interceptions: Thrips fuscipennis has been intercepted three times through CDFA’s border stations and high risk pest exclusion programs (7).

The risk Thrips fuscipennis (rose thrips) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Thrips fuscipennis is polyphagous and its hosts are grown throughout the state. This species can become established in areas of the state with warm spring and summers. Rain can wash thrips larvae from the hosts but if host plants are stressed due to drought, thrips infestations and populations can increase (4). It receives a High (3) in this category.

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

– 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: Thrips fuscipennis has a wide host range including ornamentals, fruit crops, legumes, cucumber, bind weed, meadowsweet (1). Common hosts include Roses (Rosa), Strawberry (Fragaria), bell pepper (Capsicum annuum) and white clover (Trifolium repens) and canola (Brassica napus (3). It receives a High (3) in this category.

Evaluate the host range of the pest:

– 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: Reproduction of thrips is sexual or parthenogenetic. Each female lays about 100 eggs in its life time. Fertilized eggs produce females and males are produced from unfertilized eggs. One generation is completed in a month, but this can vary depending upon temperature. Adults are poor fliers but their feathery wings allow them to be readily carried by air currents (4, 6). Eggs concealed in plant tissue can easily be transported long distances when infested plants or cuttings are moved. It receives a Medium (2) in this category.

Evaluate the natural and artificial dispersal potential of the pest:

– 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: Thrips fuscipennis is reported as a serious pest of deciduous trees and shrubs in ornamental nurseries in central and southern Poland. This was the main species encountered on plum and apple twigs in nurseries, mother apple plantations and in young orchards (2). This species can also cause fruit bronzing in strawberries resulting in lower fruit quality (1). If this species were to enter California, it would be likely to impact fruit crops and ornamental plantings. Since Thrips fuscipennis is commonly intercepted at US ports of entry, this species is likely to trigger quarantine for California commodities. Thrips can also be vectors of bacteria, fungi and viruses. It receives a High (3) in this category

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

Economic Impact: A, B, C, E

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.

5) Environmental Impact: Thrips fuscipennis is not expected to lower biodiversity or change ecosystem processes. However, it is likely to have impacts on Monterey clover (Trifolium trichocalyx), showy Indian clover (Trifolium amoenum) and pacific grove clover (Trifolium polyodon), listed as state and federally endangered species in California (8). The establishment of Thrips fuscipennis is also likely to trigger additional treatments programs at orchards, ornamental nurseries and home gardens. It receives a High (3) in this category

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

Environmental Impact: B, D

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:

Environmental Impact Score: 3

– 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 Thrips fuscipennis (rose thrips): High (14)

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: Thrips fuscipennis has never been found in the environment and 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:

Score: 0

–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: High (14)

Uncertainty:

Current ongoing integrated pest management programs against western flower thrips and other thrips species may be beneficial against Thrips fuiscipennis. It is not known how many native and wild Trifolium and other species can be impacted if Thrips fuscipennis were to get established in the state. There have been no surveys done within California nurseries and orchard planting so this species might be present in certain areas of the state.

Conclusion and Rating Justification:

Rose thrips (Thrips fuscipennis) has never been found in the environment of California and would likely have significant economic and somewhat environmental impacts if it were to enter the state. An “A”-rating is justified.

References:

Agriculture and Horticulture Development Board, United Kingdom: Thrips fuscipennis A ‘new’ pest of Strawberry – AHDB Horticulture, Accessed 02/03/2017 https://horticulture.ahdb.org.uk/sites/default/files/4%20Jude%20Bennison%20-%20Thrips%20fuscipennis.pdf | https://horticulture.ahdb.org.uk/…/4%20Jude%20Bennison%20-%20Thrips%20fuscip…

Czubik, Teresa Badowska and Olszak Remigiusz W. 2006. Thripidae in Polish plum and apple nurseries and orchards. Journal of fruit and ornamental plant research. Vol. 14 ( Suppl.3)
http://www.inhort.pl/files/journal_pdf/Suppl_3_2006/Suppl_3_full_15_2006.pdf

CABI 2016. Thrips fuscipennis http://www.cabi.org/cpc/datasheet/53734

Nakahara, Sueo 1994. The Genus Thrips Linnaeus (Thysanopetera: Thripidae) of the New World. USDA ARS Technical Bulletin: 1822, July 1994 https://naldc.nal.usda.gov/naldc/download.xhtml?id=CAT11137035&content=PDF

A. David: Commonly intercepted Thrips at U.S. Ports-of-entry from Africa, Europe, and the Mediterranean. Ill. THE Genus Thrips Linnaeus, 1758 (Thysanoptera: Thripidae).Proceedings of the Entomological Society of Washington. Jan 2008: Vol. 110, Issue 1, pg(s) 165-185 https://naldc.nal.usda.gov/download/10094/PDF

Ministry of Agriculture, British Columbia. Thrips- Biology and Control in Floriculture Crops http://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/agriculture-and-seafood/animal-and-crops/plant-health/thrips-floriculture.pdf

Pest and Damage Record Database. Plant Health and Pest Prevention Services, California Department of Food and Agriculture, Accessed: 02/03/2017 http://phpps.cdfa.ca.gov/user/frmLogon2.asp

State of California Natural Diversity Database 2012. State and federally listed Endangered, Threatened and Rare plants of California, Resource Management and Planning Division, Biogeographic Data Branch. CA Department of Fish and Game.

USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). Accessed: 02/03/2017. https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Raj Randhawa, Senior Environmental Scientist; California Department of Food and Agriculture; 1220 N Street, Sacramento, CA 95814; Tel. (916) 654-0312; plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:
Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Insects, Mites & Earthworms, Thysanoptera

Biltothrips minutus (Bhatti)

February 6, 2017 Javaid Iqbal

California Pest Rating for

Biltothrips minutus (Bhatti)

Thysanoptera: Thripidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Biltothrips minutus was collected on December 8, 2016 from the head of a cabbage (Brassica oleracea) in Hawaii. This was the first interception of this species in the United States. The insect is currently unrated by CDFA, so a pest rating proposal is needed to determine future direction.

History & Status:

Background: Biltothrips minutus is a member of the Scirtothrips genus-group and it was originally described within the genus Sericothrips. The Scirtothrips genus-group lineage is comprised of 11 genera. Only two (Scirtothrips and Anascirtothrips) are widespread globally, whereas the remaining nine genera are restricted in their distributions. The members of this group breed on a wide range of plants, but they appear to prefer tissues of the youngest leaves and fruitlets. Some species of this lineage are considered major pests¹.

Biltothrips minutus was described from West Bengal in India and has subsequently been reported from Thailand, Malaysia and the Society Islands in the Pacific Ocean. Biltothrips minutus lacks ocellar setae pair I, which is unique within this genus². No literature is available concerning its biology and host plants.

Worldwide Distribution: Biltothrips minutus was described from India and has been reported in Malaysia and Thailand¹. It was recently intercepted in Hawaii.

Official Control: Biltothrips minutus is not known to be under official control by any state or nation except for Japan where all Thripidae are listed as harmful organisms⁴.

California Distribution: Biltothrips minutus has never been found in the environment of California³.

California Interceptions: Biltothrips minutus has not been intercepted in any regulatory situation in California³.

The risk Biltothrips minutus would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Biltothrips minutus is reported in areas with climate similar to California and is expected to encounter suitable host material throughout much of state. It receives a High (3) in this category.

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

– 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: The host range for Biltothrips minutus is unknown, but being the members of Scirtothrips lineage they probably can feed on a variety of plants growing throughout. It receives a High (3) in this category.

Evaluate the host range of the pest:

– 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 famous for their high reproductive rates. They may spread long distances when infested plants are moved. It receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest:

– 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: Although there is no information available about Biltothrips minutus species as a significant economic pest, it could feed on young growth and lower crop yields. This species may lower the quality and value of nursery plants. It may also increase crop production costs by triggering additional management activities. It receives a High (3) in this category

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

Economic Impact: A B, C

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.

Economic Impact Score: 3

– 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: If Biltothrips minutus were to become established in California it is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. The presence of Biltothrips minutus in California may trigger additional chemical treatments in nurseries and agricultural production. It receives a Medium (2) in this category.

Evaluate the Environmental impact of the pest to California using the criteria below:

Environmental Impact: D

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 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.

Environmental Impact Score: (2)

– 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 Biltothrips minutus: High (14)

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Biltothrips minutus has never been found in California and receives a Not established (0) in this category.

–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: High (14)

Uncertainty:

Biltothrips minutus was recently intercepted in the United States for the first time and nothing much is known about its habitat and host range. Nevertheless, the environment of California is highly favorable for thrips species. Therefore, the uncertainty about this species is high.

Conclusion and Rating Justification:

Biltothrips minutus has never been found in the environment of California and its entry to the State has potentially significant economic and environmental impacts. An “A” rating is justified.

References:

Ng, Y.F. and Mound, L.A. 2015. Genera of the Scirtothrips genus-group (Thysanoptera, Thripidae) with a new species of Siamothrips from Malaysia. Zootaxa 4021 (2): 387-394. Accessed on 1-13 2017. https://www.researchgate.net/publication/283194234_Genera_of_the_Scirtothrips_genus-group_Thysanoptera_Thripidae_with_a_new_species_of_Siamothrips_from_Malaysia
Ng, Y.F. and Mound, L.A. 2016. Two new species of Scirtothrips genus-group (Thripidae) of Northern Peninsular Malaysia. Zootaxa 4088 (1): 141-145.
Pest and Damage Record Database, California Department of Food and Agriculture, Plant Health and Pest Prevention Services. http://phpps.cdfa.ca.gov/user/frmLogon2.asp
USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Javaid Iqbal, California Department of Food and Agriculture; 1220 N Street, Sacramento, CA 95814; Tel. (916) 403-6695; plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:
Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

Pest Rating: A

Posted by ls

Insects, Mites & Earthworms, Thysanoptera

Retithrips syriacus (Mayet): Black vine thrips

July 26, 2016 Jason Leathers

California Pest Rating for

Retithrips syriacus (Mayet): Black vine thrips

Thysanoptera: Thripidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

February 26, 2014, USDA distributed a Deregulation Evaluation of Established Pests (DEEP) report proposing to change the status of Retithrips syriacus, black vine thrips, from actionable to non-actionable for the continental United States. The thrips would remain actionable for Hawaii, Guam, and the Virgin Islands. The insect is currently unrated by CDFA, so a pest rating proposal is needed to determine future direction.

History & Status:

Background: Retithrips syriacus breeds on the leaves of a variety of plants in 29 plant families including grapes, roses, cotton, and castor oil². It may spread through trade on leaves where it has been intercepted (rarely) on various species¹.

Worldwide Distribution: Retithrips syriacus is widespread in Africa and western Asia¹. It has also been found in Brazil, Venezuela, and Puerto Rico¹. It was first detected in southern Florida in 1993¹.

Official Control: Costa Rica, Ecuador, Japan, Jordan, the Republic of Korea, Panama, and Peru list Retithrips syriacus on their harmful organism lists¹.

California Distribution: Retithrips syriacus has never been found in the environment of California.

California Interceptions: Retithrips syriacus has never been intercepted in California.

The risk Retithrips syriacus (black vine thrips) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: The present distribution of Retithrips syriacus corresponds to USDA plant hardiness zones 9-13, indicating that it may establish in much of California. 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: Retithrips syriacus feeds and breeds on a variety of plants in at least 29 plant families. The thrips receives a High (3) 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. Retithrips syriacus may move long distances in trade on nursery stock or leaves, and may be spread by wind. One of the hosts of Retithrips syriacus is castor oil plant. Castor oil plant is common and very abundant in riparian areas of Southern California. If the thrips were to enter this part of the state it is likely to spread rapidly throughout the region on this host. 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: Retithrips syriacus feeds and breeds on a wide variety of plants including economically important crops such grapes, cotton, and roses. Although the thrips has not yet caused economic damage in tropical southern Florida¹, the native distribution of the thrips tends more toward a Mediterranean climate more typical of California and the thrips may be predicted to be more damaging here. Retithrips syriacus has the potential to lower yield in these crops by feeding on leaves. The thrips may also increase crop production costs by triggering additional management activities. Retithrips syriacus is listed as a quarantine pest by multiple countries and USDA has proposed to keep the thrips actionable in Hawaii, Guam, and the Virgin Islands. Therefore it is probable that if Retithrips syriacus were to establish in California, it would trigger a loss of markets. This would be expected especially for exports of California table grapes. Retithrips syriacus receives a High (3) 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: Rosa is considered a host of Retithrips syriacus. Small-leaved rose (Rosa minutifolia) is listed as an endangered species by California and could be directly affected by the thrips. The presence of Retithrips syriacus may also trigger additional chemical treatments in agricultural production. 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 Retithrips syriacus (Black vine thrips): High (15)**

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: Retithrips syriacus has never been found in California and receives a Not established (0) in this category.

–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: High (15)

Uncertainty:

It is possible that Retithrips syriacus may be managed by existing IPM practices in agriculture.

Conclusion and Rating Justification:

Retithrips syriacus is expected to find favorable conditions in California where it may have significant economic and environmental impacts. An A-rating is justified.

References:

¹Baez, Ignacio. 2014. Deregulation Evaluation of Established Pests (DEEP); DEEP Report on Retithrips syriacus (Mayet): Black vine thrips.

²Thrips of California http://keys.lucidcentral.org/keys/v3/thrips_of_california/identify-thrips/key/california-thysanoptera-2012/Media/Html/browse_species/Retithrips_syriacus

Responsible Party:

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

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Insects, Mites & Earthworms, Thysanoptera

Pezothrips kellyanus (Bagnall): Kelly’s Citrus Thrips

March 9, 2016 Jason Leathers

California Pest Rating for

Pezothrips kellyanus (Bagnall): Kelly’s Citrus Thrips

Thysanoptera: Thripidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

In May 2015 Pezothrips kellyanus was intercepted by CDFA’s high risk programs on three shipments of leis from Hawaii. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Larvae and adult Pezothrips kellyanus feed on flowers, young leaves, and fruit¹. Where it is established it may be the most common thrips in citrus orchards³ and is considered to be a serious pest². Pupae overwinter in the soil and leaf litter and adults migrate to flowers as they emerge in the spring³. Adult females lay eggs inside the tissue of flowers, fruits, and leaves². Primary hosts are: Rutaceae: Citrus bergamia² (bergamot orange), Citrus aurantium² (orange), Citrus limonia² (lemon), Citrus spp.³; Caprifoliaceae: Lonicera spp.² (honeysuckle), Oleaceae: Jasminum fruticans² (wild jasmine), Pittosporaceae: Pittosporum tobira² (Japanese mock-orange). Other hosts include: Anacardiaceae: Mangifera indica³ (mango); Apiaceae: Daucus carota (Queen Anne’s lace), Foeniculum vulgare² (fennel); Apocynaceae: Araujia sericifera⁵ (moth plant); Asteraceae: Helianthus spp. (sunflower), Senecio spp.² (ragworts), Anthemis cotula² (stinking chamomile), Leucanthemum vulgare² (ox-eye daisy), Sonchus oleraceus² (common sowthistle), Calendula arvensis³ (field marigold), Urospermum picroides³ (prickly goldenfleece); Brassicaceae: Brassica spp.² (mustard), Brassica rapa sylvestris² (wild turnip), Sinaspis alba² (white mustard); Fabaceae: Trifolium repens² (white clover), Trifolium pratense² (red clover); Lauraceae: Persea americana (avocado); Malvaceae: Malva nicaeensis³ (bull mallow), Malva sylvestris³ (common mallow); Oleaceae: Jasminum officinale³ (jasmine); Jasminum sambac³ (Arabian jasmine), Ligustrum vulgare² (wild privet); Oxalidaceae: Oxalis pes-caprae³ (Bermuda buttercup); Pittosporaceae: Hymenosporum sp.¹ (native frangipani); Rosaceae: Eriobotrya japonica³ (loquat); Prunus dulcis (almond)³; Rubus fruticosus² (blackberry); Rubiaceae: Gardenia jasminoides³ (gardenia); Solanaceae: Lycopersicon spp.² (tomato). Pezothrips kellyanus may be transported long distances when infested plants, fresh plant parts, or soil or leaf litter is moved.

Worldwide Distribution: Pezothrips kellyanus is probably native to Australia¹. From there it has spread to New Zealand¹, New Caledonia¹, France¹, Italy¹, Greece¹, Cyprus¹, Turkey¹, Spain², Portugal², and Israel². Recent interceptions indicate that it could be present in Hawaii.

Official Control: Pezothrips kellyanus is listed as a harmful organism by Chile and Japan⁴.

California Distribution: Pezothrips kellyanus has never been found in the environment of California.

California Interceptions: From 2001 and 2015 Pezothrips kellyanus has been intercepted by CDFA 13 times on shipments of leis from Hawaii.

The risk Pezothrips kellyanus (Kelly’s Citrus Thrips) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Pezothrips kellyanus is established in areas with climates similar to California and is expected to encounter suitable host material throughout much of the state. It 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: Pezothrips kellyanus is polyphagous on plants in at least 15 families. It receives a High (3) 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: Pezothrips kellyanus has a high reproductive rate and may breed continuously throughout the year on plants that have extended flowering periods and repeated flower flushes², such as lemons. The thrips may spread long distances when infested plants, fresh plant parts, or soil and leaf litter are moved. It may also spread by hitchhiking on clothing, equipment, or animals. Pezothrips kellyanus 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: If Pezothrips kellyanus were to establish in California it may lower crop yields and lower crop value. It is considered a serious pest in citrus orchards and its feeding can lead to reduced yields and disfigure fruit with stem-end scarring, ring-scarring with halo and scurfing, and rind discoloration^2,5. This may lead to fresh market fruit being diverted to juice production and trigger chemical treatments². There are many additional crops in California that may also be affected. The presence of this thrips in California may also disrupt markets since it is listed as a harmful organism by both Japan and Chile⁴. Pezothrips kellyanus is not expected to change cultural practices, injure animals, or disrupt water supplies. It is not known as a vector of plan pathogens. It receives a High (3) 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: If Pezothrips kellyanus were to establish in California it is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It may feed on threatened and endangered species including Algodones Dunes sunflower (Helianthus niveus tephrodes), showy indian clover (Trifolium amoenum), pacific grove clover (Trifolium polyodon), and Monterey clover (Trifolium trichocalyx). The thrips is not expected to disrupt critical habitats. It is likely to trigger new chemical treatments in agriculture and by residents who find infested plants unsightly. Many of the hosts of Pezothrips kellyanus are grown as ornamentals and in home gardens in California and may be significantly impacted. Pezothrips kellyanus 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 Pezothrips kellyanus (Kelly’s Citrus Thrips): High (15)**

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: Pezothrips kellyanus has never been found in California and receives a Not established (0) in this category.

–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: High (15)

Uncertainty:

Existing IPM programs targeting other thrips that are already established in California may preclude some of the impacts from this pest.

Conclusion and Rating Justification:

Pezothrips kellyanus has never been found in California and may have significant economic and environmental impacts if it were to establish in the state. An “A” rating is justified.

References:

¹ Hoddle MS, Mound LA, Paris DL. 2012. Thrips of California. CBIT Publishing, Queensland.

http://keys.lucidcentral.org/keys/v3/thrips_of_california/identify-thrips/key/california-thysanoptera-2012/Media/Html/browse_species/Pezothrips_kellyanus.htm

² Marullo, Rita. EPPO Quarantine Bulletin. Università degli Studi di Reggio Calabria

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&ved=0CC4QFjAFahUKEwj08bHclvzGAhURoogKHTm0CDk&url=http%3A%2F%2Fwww.eppo.int%2FQUARANTINE%2FPest_Risk_Analysis%2FPRAdocs_insects%2F06-12760%2520DS%2520PEZTKE.doc&ei=LZi2VbSnH5HEogS56KLIAw&usg=AFQjCNHrfJMlhro7kb2f880G5VK35jYDSA&bvm=bv.98717601,d.cGU&cad=rja

³ Vassiliou, V.A. 2010. Ecology and behavior of Pezothrips kellyanus (Thysanoptera: Thripidae) on citrus. Journal of Economic Entomology 103(1):47-53. http://www.ncbi.nlm.nih.gov/pubmed/20214367

⁴ USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

⁵ Navarro-Campos, Cristina, Apostolos Peskas, Amparo Aguilar, and Ferran Garcia Mari. 2013. Factors influencing citrus fruit scarring by Pezothrips kellyanus. Journal of Pest Science http://www.researchgate.net/publication/235993907_Factors_influencing_citrus_fruit_scarring_caused_by_Pezothrips_kellyanus

Responsible Party:

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

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