California Pest Rating for

Name: Pseudocneorhinus bifasciatus Roelofs (twobanded Japanese weevil)

Synonym: Callirhopalus bifasciatus (Roelofs)

Order: Coleoptera

Family: Curculionidae

Pest Rating: A

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PEST RATING PROFILE

Initiating Event:

Pseudocneorhinus bifasciatus is currently Q-rated.  A permanent pest rating proposal is required to support an official pest rating.

History & Status:

Background:  Pseudocneorhinus bifasciatus is a stout, convex, and pear-shaped weevil with a short, blunt snout, and elytra much broader than its pronotum. It is approximately 5 mm long, and is covered with brown and grey scales that form two bands across the elytra (Thomas, 2005). The elytra are fused, and the hind wings are absent, so this weevil cannot fly. The adult weevils feed during the day on leaves.  They are easy to overlook due to their subdued brown coloration (Smith,1955).  They can cause significant damage to plants when they are abundant. This weevil is highly polyphagous and is known to feed on over 100 species of plants.  Recorded hosts include multiflora rose (Rosa multiflora), rose, azalea (Rhododendron spp.), privet (Ligustrum spp.), azalea, forsythia, geranium, hemlock, mountain laurel, lilac, strawberry, flowering dogwood, and perennial phlox.  In the northeastern United States, Pseudocneorhinus bifasciatus has one generation per year with egg laying taking place from the middle of May through October (Gyeltshen and Hodges, 2016).  Eggs are laid on fallen leaves within leaf-folds, and the edges of the leaf is then sealed by the weevil to form a “pod” (Zepp, 1978).  An egg “pod” contains one to nine eggs (Zepp, 1978).  The eggs hatch in 14 to 18 days (Allen, 1959).  The newly hatched larvae leave the “pod” and burrow into the soil. The larvae live in the soil and feed on the roots of host plants, but the extent of damage from their feeding is not well documented.  Allen (1959) found as many as 150 larvae per square foot, at depths ranging from one to nine inches, underneath infested privet hedges in New Jersey.  Larvae were found at depths ranging from one to nine inches (Allen, 1959).  These larvae started to pupate by early May, and adults emerged in late June and early July (Allen, 1959).  Although the weevil has a wide range of hosts, the Rosaceae family may be particularly vulnerable to this pest.  For example, one study showed that this weevil had the greatest reproductive success when adults were fed on foliage of Rosa multiflora Thunb. (Rosaceae) compared with four other species of other ornamental plants in three other families (Maier, 1983).  Another study found larvae of this weevil to cause damage to the roots of peach trees in Georgia (peaches are in the family Rosaceae; Cottrell and Horton, 2013).

Worldwide Distribution:  Pseudocneorhinus bifasciatus is native to China, Japan, Korea, Mongolia, and eastern Siberia.  It has been established on the east coast of the United States for more than 100 years and it is currently known to occur there from New England south to northern Florida and west to Illinois and Indiana (Thomas, 2005).  It has also been found in Oklahoma, although the distribution of the weevil in that state is unknown (Rebek and Grantham, 2008).

Official Control: Pseudocneorhinus bifasciatus is not known to be under official control.

California Distribution:  Pseudocneorhinus bifasciatus is not known to be present in California (Symbiota Collections of Arthropods Network).

California Interceptions:  Pseudocneorhinus bifasciatus was intercepted in a West Sacramento postal facility in an out-of-state shipment of crabapple in August 2015 (CDFA, 2015).

The risk Pseudocneorhinus bifasciatus would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: The weevil’s distribution extends from New England to Florida, indicating a wide temperature tolerance. It is not known if there are other climate limitations. This weevil is highly polyphagous, and it is presumed that suitable host plants are present throughout much of California.  Therefore, it receives a High (3) in this category.

– 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: Pseudocneorhinus bifasciatus, has been reported to feed on more than 100 species of plants in more than 25 families. It is primarily known for damaging ornamental plants, but it has been found to also damage vegetable and field crops (Day, 2014; Thomas, 2005). Therefore, it receives a High (3) in this category.

– 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: Pseudocneorhinus bifasciatus reproduces parthogenetically (Takenouchi et al, 1983).  This high reproductive capacity is offset by a limited dispersal potential.  The weevil’s wing covers are fused rendering it incapable of flight.  It could be dispersed through the movement of infected nursery stock (Wheeler and Boyd, 2005).  Therefore, it receives a Medium (2) in this category.

– 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: As described previously, Pseudocneorhinus bifasciatus has a very wide range of hosts including field and vegetable crops (Thomas, 2005; Day, 2014).  The weevil has the potential of lowering the value of nursery crops and the yield of agricultural crops.  Therefore, it receives a Medium (2) in this category.

Economic Impact:  A, B

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: 2

– 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 Pseudocneorhinus bifasciatus became established in California, it could attack a wide variety of ornamental and garden plants. The impact of the infestation could trigger treatment programs.  This pest may also pose a threat to endangered species such as Rosa minutifolia and Potentilla hickmannii.  Therefore, this beetle receives a High (3) in this category.

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

Environmental Impact: B, D, E

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.

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 Pseudocneorhinus bifasciatus: High (13)

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: Pseudocneorhinus bifasciatus is not known to occur in California.  It 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:

7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (13)

Uncertainty:

There is significant uncertainty regarding the suitability of the California climate and the ability of Pseudocneorhinus bifasciatus to become established in California. It apparently can tolerate a wide range of temperatures, as shown by its broad distribution in the eastern United States, but the suitability of the drier climate of California is unknown.  The weevil has been found in a relatively dry western state (Oklahoma), but the extent of its incursion there is unknown (Rebek and Grantham, 2008).

Conclusion and Rating Justification:

Pseudocneorhinus bifasciatus is a weevil that attacks a wide range of hosts.  If it can become established in California, it poses an economic and environmental threat to the state.  For these reasons, an “A” rating is justified.

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References:

Allen, H.W. 1957.  A Japanese weevil abundant in the Philadelphia area.  Entomological News 68: 169-174.

Allen, H.W. 1959. The Japanese weevil Pseudocneorhinus bifasciatus Roelofs. Journal of Economic Entomology 52: 586-587.

CDFA.  2015.  Detector dogs do it again!  Planting Seeds – Food & Farming News from CDFA. Accessed:  May 4, 2018  http://plantingseedsblog.cdfa.ca.gov/wordpress/?p=9310

Cottrell, T.T. and Horton, D.L.  2013.  Emergence of root-feeding weevils (Coleoptera: Curculionidae) in central Georgia peach orchards.  Journal of Entomological Sciences 48: 184-194.

Day, E.R.  2014.  Japanese Weevil.  444-624 (ENTO-98NP).  VCE Publications. Virginia Cooperative Extension, Virginia Tech, and Virginia State University.

Gayeltshen, J. and Hodges, A.  2016.  Twobanded Japanese Weevil, Pseudocneorhinus bifasciatus Roelofs (Insecta: Coleoptera: Curculionidae).  EENY361.  Entomology and Nematology Department, University of Florida; IFAS Extension.

Maier, C.T.  1983.  Influence of host plants on the reproductive success of the parthenogenetic Two-Banded Japanese Weevil, Callirhopalus bifasciatus (Roelofs) (Coleoptera: Curculionidae).  Environmental Entomology 12: 1197-1203.

Rebek, E.J., and Grantham, R.  2008.  New Oklahoma insect pest of woody ornamentals: Japanese weevil.  Plant Disease and Insect Advisory.  Oklahoma State University Extension. Vol. 7, No. 33.

Smith, F.F. 1955. Scientific Notes: Notes on the biology and control of Pseudocneorhinus bifasciatus. Journal of Economic Entomology 48:628-629.

Symbiota Collections of Arthropods Network.  Accessed May 22, 2018. http://scan-bugs.org/portal/taxa/index.php?taxon=Pseudocneorhinus+bifasciatus&formsubmit=Search+Terms

Takenouchi, Y., Suomalainen, E., Saura, A., and Lokki, J.  1983.  Genetic polymorphism and evolution in parthenogenetic animals.  XII.  Observations on Japanese polyploid Curculionidae (Coleoptera).  Japanese Journal of Genetics 58:153-157.

Thomas, M.C. 2005. Pest Alert: The twobanded Japanese weevil (Pseudocneorhinus bifasciatus Roelofs), an invasive pest new to Florida (Coleoptera: Curculionidae).  Florida Department of Agriculture and Consumer Services.  DACS-P-01673.  Accessed: May 2, 2018.  https://www.freshfromflorida.com/content/download/66258/1600078/Pseudocneorhinus_bifasciatus,_The_two_banded_Japanese_Weevil.pdf

Wheeler, A.G., Jr., and Boyd, D.W., Jr. 2005. Distribution of an invasive weevil, Pseudocneorhinus bifasciatus Roelofs, in the southeastern United States. Journal of

Entomological Science 40: 25-30.

Zepp, D.B.  1978.  Egg pod formation by Callirhopalus (subg. Pseudocneorhinus) bifasciatus (Roelofs) (Coleoptera: Curculionidae: Eremninae).  Coleopterists Bulletin 32: 311-313.

Photo: By Judy Gallagher [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons

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Author:

Karen Olmstead, Environmental Scientist; California Department of Food and Agriculture; 1220 N Street, Sacramento, CA 95814; Tel. (916) 403-6879; plant.health@cdfa.gov

Responsible Party:

Jason Leathers, 2800 Gateway Oaks, Sacramento CA  95833; (916) 654-1211; plant.health@cdfa.gov

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Comment Period:* CLOSED

7/25/18 – 9/08/18

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*NOTE:

You must be registered and logged in to post a comment.  If you have registered and have not received the registration confirmation, please contact us at plant.health[@]cdfa.ca.gov.

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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.

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Pest Rating: A

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Posted by ls 

California Pest Rating for

Longhorned Beetle | Plagionotus arcuatus (Linnaeus)

Coleoptera: Cerambycidae

Pest Rating: A

 

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PEST RATING PROFILE

Initiating Event:

Plagionotus arcuatus is currently Q-rated.  A permanent pest rating proposal is required to support an official pest rating.

History & Status:

Background:  Adult Plagionotus arcuatus (P. arcuatus) are 9-20 mm in length and black with yellow bands and spots (Lazarev, 2010). The biology of this species does not appear to be well-studied.  The larvae live in dead (reports suggest the wood has usually been dead for only several months) wood of deciduous trees, including Carpinus, Castanea, Fagus, Prunus, Robinia, Salix, and Quercus spp.  Reports suggest that this beetle attacks wood that is relatively fresh (i.e., dead, but recently-killed), perhaps several months old (Barševskis and Savenkov, 2013; Faggi et al., 2010; Ilić and Ćurčić, 2013; Jonsell, 2008; Sama et al., 2005; Vodka, 2007).  Escherich (1916) reported that this damage lowers the value of oak timber.  No evidence was found suggesting that P. arcuatus attacks living trees.  Other species of Plagionotus also appear to be restricted to dead trees, although Moraal and Hilszczanski (2000) suggested that one or more species in the genus may have contributed to the death of oak trees in Poland.

Worldwide Distribution:  Plagionotus arcuatus has been reported from northern Africa (including Libya), central Asia, the Caucasus (including Georgia and Armenia), Europe (including Bulgaria, Hungary, Italy, Latvia, Macedonia, Spain, Serbia, and Sweden), Iran, Syria, and Turkey (Barševskis and Savenkov, 2013; Faggi et al., 2010; Georgiev and Hubenov, 2006; Ilić and Ćurčić, 2013; Jonsell, 2008; Keszthelyi, 2015; Özdikmen, 2014; Peña, 2002; Plewa et al., 2015).

Official Control: Plagionotus arcuatus is not known to be under official control anywhere.

California Distribution:  Plagionotus arcuatus is not known to be present in California (Symbiota Collections of Arthropods Network).

California Interceptions:  Plagionotus arcuatus was intercepted on dunnage that was suspected to have come from Europe in 1996 (CDFA Pest and Damage Report Database, 2018).

The risk Plagionotus arcuatus would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Plagionotus arcuatus is widely distributed and is found in areas with a range of temperate climates, including Mediterranean. The species feeds on a variety of deciduous trees, including the genera Prunus and Quercus, which are widely distributed in California.  The species is likely to become established over a large portion of California.  Therefore, arcuatus receives a High (3) in this category.

– 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: Plagionotus arcuatus is reported to feed on at least seven genera from five different families of deciduous trees. Therefore, it receives a High (3) in this category.

– 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: Plagionotus arcuatus can presumably fly.  This beetle can also disperse through movement of firewood, as shown by the interception of multiple living adults in firewood on the island of Majorca (Díaz-Calafut et al., 2017).  Therefore, it receives a Medium (2) in this category.

– 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: Plagionotus arcuatus attacks recently-cut wood and was reported to reduce the quality of oak timber.  Avoiding damage from this beetle may require changes in the timing of timber harvest.  Forest product (including timber) sales in California totaled $1.4 billion in 2012 (McIver et al., 2015).  Therefore, it receives a Medium (2) in this category.

Economic Impact:  B, D

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:  2

– 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 Plagionotus arcuatus became established in California, it could possibly compete with native beetles that live in and feed on recently-dead wood. Therefore, it receives a Medium (2) in this category.

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

Environmental Impact: A

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.

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 Plagionotus arcuatus: Medium (11)

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Plagionotus arcuatus is not known to be present in California.  It 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:

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

Uncertainty:

One report suggests that species in the genus Plagionotus may be capable of attacking living trees (Moraal and Hilszczanski, 2000).  If so, P. arcuatus may be capable of attacking living trees and the potential impacts of it in California would be greater than considered in this proposal.  However, if this species was capable of inflicting significant damage to living trees, it seems likely that this damage would have been recognized, considering its wide distribution and host range.

Conclusion and Rating Justification:

Plagionotus arcuatus is not known to be present in California.  Although it is only known to attack dead trees, it could lower the value of cut timber and thus poses a threat to the timber industry of California.  For these reasons, an “A” rating is justified.

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References:

Barševskis A., and Savenkov, N.  2013.  Contribution to the knowledge of long-horned beetles (Coleoptera: Cerambycidae) in Latvia.  Baltic Journal of Coleopterology 13:91-102.

CDFA Pest and Damage Report Database.  2018.  Plagionotus arcuatus.  Plant Health and Pest Prevention Services. CA Department of Food and Agriculture.  Accessed March 19, 2018: https://pdr.cdfa.ca.gov/PDR/pdrmainmenu.aspx

Escherich, K.  1916.  Clytus arcuatus L. (Cerambycide) als schlimmer technischer Eichenschädling.  Naturwissenschaftliche Zeitschrift für Land- und Forstwirtschaft 14:272-273.

Faggi, M., Nappini, S., and Biscaccianti, A. B.  2010.  Studies on longhorn beetles (Coleoptera Cerambycidae) of the Monte Ruffino Nature Reserve and Bosco del Sasseto Natural Monument (Lazio, Central Italy).  Journal of Zoology 93:31-45.

Georgiev, G., and Hubenov, Z.  2006.  Vertical Distribution and Zoogeographical Characteristics of Cerambycidae (Coleoptera) Family in Bulgaria.  Acta Zoologica Bulgarica 58:315-343.

Ilić, N., and Ćurčić, S.  2013.  The longhorn beetles (Coleoptera: Cerambycidae) of Rtanj Mountain (Serbia).  Acta Entomologica Serbica 18:69-04.

Jonsell, M.  2008.  Saproxylic beetle species in logging residues: Which are they and which residues do they use?  Norwegian Journal of Entomology 55:109-122.

Keszthelyi, S.  2015.  Diversity and seasonal patterns of longhorn beetles (Coleoptera: Cerambycidae) in the Zselic region, Hungary. North-Western Journal of Zoology 11:62-69.

Lazarev, M. A.  2010.  New subspecies of Plagionotus arcuatus (Linnaeus, 1758) from Transcaucasia and Kyrgyzstan (Coleoptera: Cerambycidae).  Studies and Reports, Taxonomical Series 6:149-164.

Moraal, L. G., and Hilszczanski, J.  2000.  The oak buprestid beetle, Agrilus biguttatus (F.) (Col., Buprestidae), a recent factor in oak decline in Europe.  Anzeiger für Schädlingskunde 73:134-138.

McIver, C. P., Meek, J. P., Scudder, M. G., Sorenson, C. B., Morgan, T. A., and Christensen, G. A.  2012.  California’s Forest Products Industry and Timber Harvest, 2012.  United States Department of Agriculture, Forest Service, Pacific Northwest Research Station, General Technical Report PNW-GTR-908.

Özdikmen, H.  2014.  Turkish red list categories of longicorn beetles (Coleoptera: Cerambycidae) Part VIII-Subfamily Cerambycinae: Anaglyptini and Clytini.  Munis Entomology & Zoology Journal 9:687-712.

Peña, C. F. G.  2002.  Catálogo de los Cerambícidos de Aragón.  Catalogus de la Entomofauna Aragonesa 27:3-43.

Plewa, R., Marczak, D., Borowski, J., Mokrzycki, T., Jakubowski, M., and Górski, P.  2015.  New Data on the Occurrence of Longhorn Beetles (Coleoptera: Cerambycidae) in the Republic of Macedonia.  Acta Zoologica Bulgarica 67:43-50.

Symbiota Collections of Arthropods Network.  Accessed March 16, 2017: http://scan1.acis.ufl.edu

 

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Author:

Kyle Beucke, 1220 N Street, Room 221, Sacramento, CA, 95814, 916-403-6741; plant.health[@]cdfa.ca.gov.

Responsible Party:

Jason Leathers, 2800 Gateway Oaks, Sacramento CA 95833, (916) 654-1211, plant.health[@]cdfa.ca.gov

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Comment Period:* CLOSED

7/24/18 – 9/07/18

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*NOTE:

You must be registered and logged in to post a comment.  If you have registered and have not received the registration confirmation, please contact us at plant.health[@]cdfa.ca.gov.

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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.

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Pest Rating: A

 

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Posted by ls 

California Pest Rating  for

Palmetto weevil | Rhynchophorus cruentatus (Fabricius)

Coleoptera: Dryophthoridae

Pest Rating: A

 

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PEST RATING PROFILE

Initiating Event:

Rhynchophorus cruentatus is currently Q-rated.  A permanent pest rating proposal is required to support an official pest rating.

History & Status:

Background:  Adult R. cruentatus are large weevils that measure 2.7 to 3.3 centimeters in length (Wattanapongsiri, 1966).  They are dull to shining and reddish-brown to black (or a pattern of both) in color (Giblin-Davis et al., 1994).  This species attacks palms.  Eggs are laid in petiole bases or wounds in the palm.  The larvae feed on the tissue internally and form a cocoon made from plant fiber, in which they pupate.  The feeding damage can compromise the structural integrity of the palm to the extent that the crown falls over (Giblin-Davis and Howard, 1988).  The larval feeding damage is cryptic because it occurs inside the palm, and it is often not apparent until death of the tree is inevitable (Hunsberger et al., 2000).  In the case of Sabal palmetto, which is native in the beetle’s area of distribution, R. cruentatus apparently only attacks stressed trees.  However, in the case of introduced palm species, including Phoenix canariensis, apparently healthy trees are attacked and killed, sometimes in large numbers.  For example, 97% of the Phoenix canariensis in one Florida nursery were killed; the damage was estimated at $285,000-$380,000 (Hunsberger et al., 2000).  Besides Phoenix and Sabal, other genera of palms reported to be attacked include Caryota, Cocos, Latania, Pritchardia, Roystonea, Thrinax, and Washingtonia (Hunsberger et al., 2000; Weissling and Broschat, 1999).  Other non-palm plants may also be utilized by this beetle, but little information is available regarding this (Wattanapongsiri, 1966).

Other Rhynchophorus species are important palm pests, for example R. ferrugineus and R. palmarum.  Rhynchophorus palmarum is a vector of the nematode Bursaphelenchus cocophilus, which causes red ring disease of palms.  This nematode is not yet known to occur in the United States.  The disease affects Phoenix dactylifera and P. canariensis, which are important crop and ornamental trees in California (Hodel, 2016).  If this nematode was introduced to the United States, R. cruentatus could possibly vector it (Griffith, 1987).

Worldwide Distribution:  Rhynchophorus cruentatus is native to the southeastern United States and is found from South Carolina south to Florida (including the Florida Keys) and west to Texas.  The species has also been reported from the Bahamas (Andros Island), which may represent an introduction (Turnbow and Thomas, 2008; Wattanapongsiri, 1966).

Official Control: Rhynchophorus cruentatus is not known to be under official control anywhere.

California Distribution:  Rhynchophorus cruentatus is not known to be present in California (Symbiota Collections of Arthropods Network).

California Interceptions:  Rhynchophorus cruentatus was intercepted at a border station on palm fronds from Florida in 2011 (CDFA Pest and Damage Report Database, 2018).

The risk Rhynchophorus cruentatus would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Two other Rhynchophorus species that are native to the tropics, ferrugineus and R. vulneratus, have become established in areas that do not have tropical climates, including Mediterranean Europe and southern California. Rhynchophorus cruentatus is found in the temperate to subtropical southeastern United States.  Considering the climatic flexibility of other species in the genus, it seems likely that a significant portion of California could offer a suitable climate for R. cruentatus.  Regarding host plants, palms (including known host species, such as Phoenix canariensis) are planted widely in California.  Therefore, Rhynchophorus cruentatus receives a Medium (2) in this category.

– 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: Rhynchophorus cruentatus is reported to feed on eight genera of palms. Therefore, it receives a Medium (2) in this category.

– 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: Rhynchophorus cruentatus fly (Weissling et al., 1994).  The species could also possibly be moved with palms, both whole plants as well as fronds.  Therefore, it receives a Medium (2) in this category.

– 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: Rhynchophorus cruentatus attacks palms, including the genera Phoenix and Washingtonia.  If this beetle became established in California, it would threaten the date industry in southeastern California and (in a much larger area) ornamental palms.  Ornamental palms are a $70 million industry in California and date production in the state was approximately $47 million in 2016 (Hoddle).  By killing trees, cruentatus would lower yield in both industries.  As mentioned above, in Background, R. cruentatus could possibly vector the nematode that causes red ring disease in palms.  Therefore, it receives a Medium (2) in this category.

Economic Impact:  A, 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.

Economic Impact Score:  2

– 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: Rhynchophorus cruentatus is reported to attack Washingtonia Groves of the native W. filifera are present in the deserts of southern California, and they could be threatened by the establishment of R. cruentatus.  Palms that are known hosts of R. cruentatus, including Phoenix and Washingtonia species, are widely planted in California.  If R. cruentatus became established in the state, it could impact home and urban plantings of these trees, and this could trigger treatment programs.  Therefore, it receives a High (3) in this category.

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

Environmental Impact:  A, D, E

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.

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 Rhynchophorus cruentatus: 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: Rhynchophorus cruentatus is not known to be present in California.  It 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:

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

Uncertainty:

The demonstrated ability for other Rhynchophorus species that are native to tropical areas to invade temperate areas (e.g., Europe) is considered to be evidence that R. cruentatus could possibly become established in California, even though this species is currently known to occur in areas with a subtropical or tropical climate.  Rhynchophorus cruentatus has not been proven to vector the nematode B. cocophilus.  The desert areas where the native groves of Washingtonia filifera occur may not have a suitable climate for the establishment of R. cruentatus.  If so, these native palm groves are not at risk from this beetle.

Conclusion and Rating Justification:

Rhynchophorus cruentatus feeds on and kills palm trees, and it is not known to be present in California.  This species poses a threat to the economy and environment of the state.  For these reasons, a “A” rating is justified.

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References:

CDFA Pest and Damage Report Database.  2018.  Rhynchophorus cruentatus.  Plant Health and Pest Prevention Services. CA Department of Food and Agriculture.  Accessed April 11, 2018: https://pdr.cdfa.ca.gov/PDR/pdrmainmenu.aspx

Giblin-Davis, R. M. and Howard, F. W.  1988.  Notes on the palmetto weevil, Rhynchophorus cruentatus (Coleoptera: Curculionidae).  Proceedings of the Florida State Horticultural Society 101:101-107.

Giblin-Davis, R. M., Weissling, T. J., Oehlschlager, A. C., and Gonzalez, L. M.  1994.  Field response of Rhynchophorus cruentatus (Coleoptera: Curculionidae) to its aggregation pheromone and fermenting plant volatiles.  Florida Entomologist 77:164-172.

Griffith, R.  1987.  Red ring disease of coconut palm.  Plant Disease 71:193-196.

Hoddle, M.  Has the South American palm weevil, Rhynchophorus palmarum, established in southern California?  University of California, Riverside, Center for Invasive Species Research. Accessed November 17, 2017: http://cisr.ucr.edu/palmarum.html

Hodel, D. R., Marika, M. A., and Ohara, L. M.  2016.  The South American palm weevil.  PalmArbor 2016-3:1-27.

Hunsberger, A. G. B., Giblin-Davis, R. M., and Weissling, T. J.  2000.  Symptoms and population dynamics of Rhynchophorus cruentatus (Coleoptera: Curculionidae) in Canary Island date palms.  Florida Entomologist 83:290-303.

Symbiota Collections of Arthropods Network.  Accessed April 11, 2018. http://scan1.acis.ufl.edu

Turnbow, R. H. and Thomas, M. C.  2008.  An annotated checklist of the Coleoptera (Insecta) of the Bahamas.  Insecta Mundi 34:1-64.

Wattanapongsiri, A.  1966.  A Revision of the Genera Rhynchophorus and Dynamis (Coleoptera: Curculionidae).  Ph.D. thesis.  Oregon State University.

Weissling, T. J. and Broschat, T. K.  1999.  Integrated management of palm pests.  Proceedings of the Florida State Horticultural Society 112:247-250.

Weissling, T. J., Giblin-Davis, R. M., Center, B. J., and Hiyakawa, T.  1994.  Flight behavior and seasonal trapping of Rhynchophorus cruentatus (Coleoptera: Curculionidae).  Annals of the Entomological Society of America 87:641-647.

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Author:

Kyle Beucke, 1220 N Street, Room 221, Sacramento, CA, 95814, 916-403-6741; plant.health[@]cdfa.ca.gov.

Responsible Party:

Jason Leathers, 2800 Gateway Oaks, Sacramento CA 95833, (916) 654-1211, plant.health[@]cdfa.ca.gov

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Comment Period:* CLOSED

7/3/18 – 8/17/18

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*NOTE:

You must be registered and logged in to post a comment.  If you have registered and have not received the registration confirmation, please contact us at plant.health[@]cdfa.ca.gov.

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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.

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Pest Rating: A

 

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Posted by ls 

California Pest Rating  for 

(New Guinea Sugarcane Weevil) | Rhabdoscelus obscurus (Boisduval) 

Coleoptera: Curculionidae

Pest Rating: A

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PEST RATING PROFILE

Initiating Event:

This weevil was recently intercepted on cut ginger flowers from Hawaii (190P06619908).  The species is currently Q-rated, and a permanent pest rating proposal is required to support an official pest rating.

History & Status:

Background: Adult Rhabdoscelus obscurus are 12-14 mm in length and reddish-brown with a longitudinal black stripe on the pronotum.  The larvae are white, legless grubs with a dark head capsule and are approximately 15 mm in length (Molet, 2013).  This weevil is a pest of sugarcane and palms.  The larvae tunnel and feed inside stalks, which leads to stalk breakage.  Prior to pupating, they build a fibrous cocoon.  This species appears to currently be restricted to tropical and subtropical areas.

Worldwide Distribution: Rhabdoscelus obscurus is native to New Guinea and has been introduced to much of the tropical western Pacific, including Indonesia, Japan, Malaysia, Taiwan, and numerous Pacific islands (Beardsley et al., 1995; Molet, 2013; Zimmerman, 1968).  It has also been introduced to Australia (Reddy et al., 2012).  In the United States, it has been present in Hawaii since the mid-1800s (Waggy and Beardsley, 1974).  The species is not known to occur in the continental United States.

Official Control: Rhabdoscelus obscurus is listed as a quarantine pest by the EPPO, and is considered reportable by USDA-APHIS-PPQ (EPPO, 2017).  The species has been controlled in Hawaii through the introduction of a tachinid fly parasitoid (Waggy and Beardsley, 1974; Beardsley et al., 1995).

California Distribution: Rhabdoscelus obscurus is not known to be present in California.

California Interceptions: Rhabdoscelus obscurus has been intercepted in California twice, once on cut ginger flowers from Hawaii in 2017 and once on a shipment of pineapple from Hawaii in 2004 (CDFA Pest and Damage Report Database, 2017).

The risk Rhabdoscelus obscurus would pose to California is evaluated below.

Consequences of Introduction:

1)  Climate/Host Interaction: Rhabdoscelus obscurus is currently restricted to tropical and subtropical areas.  It could become established in a limited portion of southern California.  Therefore, it receives a Low (1) in this category.

– 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: Rhabdoscelus obscurus is a major pest of sugarcane and also feeds on other monocots, including numerous palms as well as bananas, some grasses, and corn (Beardsley et al., 1995; EPPO, 2017; Molet, 2013).  Therefore, it receives a High (3) in this category.

– 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: Rhabdoscelus obscurus flies and it is capable of being introduced to new locations; much of its present distribution is due to such introductions.  The species has been intercepted 19 times (as of 2012) at United States ports of entry on infested plant material, so can be artificially dispersed that way (Molet, 2013).  Therefore, it receives a Medium (2) in this category.

– 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: Rhabdoscelus obscurus is a significant pest of sugarcane and palms.  The species causes significant mortality of palms in the Pacific, and it is a palm nursery pest in Australia (Reddy et al., 2012).  If established in California, it could impact palm nurseries, lowering yield.  Ornamental palms are a $70 million industry in California (Hoddle).  The other California industry that could be impacted by this pest is sugarcane.  Sugarcane is either currently being grown in, or is planned to be grown in the Imperial Valley, where a sugarcane-based sugar and biofuels initiative is underway.  If R. obscurus was able to become established in the Imperial Valley, which may not be likely, it could lower yield of sugarcane there.  An extensive sugarcane industry exists in the southeastern United States, and the climate in that region would likely be more favorable for the establishment of this pest.  The possibility of the spread of R. obscurus to the southeastern United States and other countries could lead to a loss of markets for ornamental palms from California.  Rhabdoscelus obscurus receives a Medium (2) in this category.

Economic Impact:  A, 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:  2

– 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 R. obscurus became established in California, it could impact ornamental plantings of palms, which are an important part of the California landscape.  The species could also potentially spread to groves of the only species of palm native to California, Washingtonia filifera, although this is somewhat unlikely, considering that this weevil is restricted to wet tropical and sub-tropical climates and these palms occur in the desert.  Therefore, Rhabdoscelus obscurus receives a High (3) in this category.

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

Environmental Impact:  A, E

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.

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 Rhabdoscelus obscurus: 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: Rhabdoscelus obscurus is not known to occur in California.  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:

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

Uncertainty:

Rhabdoscelus obscurus clearly has the potential to become established in new areas and cause great harm to sugarcane and palms, because it has already done so in much of the Pacific.  However, it is possible that the climate in California will not be suitable for the establishment of this species.

Conclusion and Rating Justification:

Rhabdoscelus obscurus is a weevil pest of sugarcane and palms that is not known to be present in California.  It could become established in restricted areas of California.  If this happened, it could cause damage to ornamental palms (and possibly the one native species).  The planned sugarcane-based industries in the Imperial Valley would also be threatened.  An “A” rating is justified.

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References:

Beardsley, J. W., Leeper, J. R., Topham, M., and Waggy, S. L.  1995.  New Guinea sugarcane weevil.  pp. 183-184 in (Nechols, J.R., Andres, L.A., Beardsley, J.W., Goeden, R.D., and Jackson, C.G., Biological control in the western United States.  University of California Division of Agriculture and Natural Resources, Oakland, California.

CDFA Pest and Damage Report Database.  2017.  Rhabdoscelus obscurus.  Plant Health and Pest Prevention Services. CA Department of Food and Agriculture.  Accessed November 28, 2017: https://pdr.cdfa.ca.gov/PDR/pdrmainmenu.aspx

EPPO.  2017.  EPPO Global Database (available online).  Accessed September 7, 2017: https://gd.eppo.int

Hoddle, M.  Has the South American palm weevil, Rhynchophorus palmarum, established in southern California?  University of California, Riverside, Center for Invasive Species Research. Accessed November 17, 2017: http://cisr.ucr.edu/palmarum.html

Molet, T.  2013.  CPHST pest datasheet for Rhabdoscelus obscurus.  USDA-APHIS-PPQ-CPHST.  Accessed September 7, 2017: http://download.ceris.purdue.edu/file/3061

Reddy, G. V. P., Shi, P., Mann, C. R., Mantanona, D. M. H., and Dong, Z.  2012.  Can a semiochemical-based trapping method diminish damage level caused by Rhabdoscelus obscurus (Coleoptera: Curculionidae)?  Annals of the Entomological Society of America 105:693-700.

Symbiota Collections of Arthropods Network.  Accessed November 28, 2017: http://scan1.acis.ufl.edu

Waggy, S. L. and Beardsley, J. W.  1974.  Biological studies on two sibling species of Lixophaga (Diptera: Tachinidae), parasites of the New Guinea sugarcane weevil, Rhabdoscelus obscurus (Boisduval).  Proceedings of the Hawaiian Entomological Society 21:485-494.

Zimmerman, E. C.  1968.  Rhynchophorinae of southeastern Polynesia.  Pacific Insects 10:47-77.

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Author:

Kyle Beucke, 1220 N Street, Room 221, Sacramento, CA, 95814, 916-403-6741; plant.health[@]cdfa.ca.gov.

Responsible Party:

Jason Leathers, 2800 Gateway Oaks, Sacramento CA 95833, (916) 654-1211, plant.health[@]cdfa.ca.gov

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Comment Period:* CLOSED

7/3/18 – 8/17/18

---

*NOTE:

You must be registered and logged in to post a comment.  If you have registered and have not received the registration confirmation, please contact us at 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

 

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Posted by ls 

California Pest Rating  for

Garden Chafer | Phyllopertha horticola (L.)

Coleoptera: Scarabaeidae: Rutelinae

Pest Rating: A

 

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PEST RATING PROFILE

Initiating Event:

Phyllopertha horticola is currently Q-rated.  A permanent pest rating proposal is required to support an official pest rating.

History & Status:

Background:  Adult Phyllopertha horticola measure 8.5 to 12 mm in length and have red-brown elytra, a metallic blue or green pronotum, and a hairy lower (ventral) surface (Agricultural Research Service, 1957).  They have a one-year life cycle (Hann et al., 2015).  Both adults and larvae feed on living plant tissue and cause economic damage (Ruther and Mayer, 2005).  The adults feed on leaves of many different plants, including fruit trees, and they also feed on fruit, including apples, and flowers (Agricultural Research Service, 1957; Hill, 1987). They have been shown to be attracted strongly to plant volatiles, which could explain why this beetle tends to occur in dense aggregations near damaged (chewed) plant tissue (Jackson, 2006; Ruther and Mayer, 2005). The larvae live underground and feed on roots, including those of apple and grasses (Agricultural Research Service, 1957).  They are reported to be the most important white grub damaging agricultural grassland in the Austrian alps (Hann et al., 2015), and they were also reported to be a significant pest in turf grass in the United Kingdom (Mabbett, 2009).  This beetle is reported to be a pest of strawberry and sea buckthorn in Latvia, although the life stage responsible for damage was not reported (Petrova et al., 2013; Stalažs, 2015).  Damage in Europe has been estimated to be on the order of hundreds of millions of Euros each year, and the damage is apparently increasing (Pernfuss et al., 2005). When this beetle is abundant, predators, including birds and mammals, are attracted and this can create problems.  For example: Gulls attracted to flying adult P. horticola created an aviation hazard in Norway, and birds feeding on the larvae of this beetle damage turfgrass (Aas et al., 2008; Mabbett, 2009).

Worldwide Distribution:  Phyllopertha horticola is found in Europe (including Austria, Latvia, Norway, and the United Kingdom), Russia, and Tibet (Aas et al., 2008; Agricultural Research Service, 1957; Hann et al., 2015; Petrova et al., 2013; Stalažs, 2015).

Official Control: Phyllopertha horticola is not known to be under official control anywhere.

California Distribution:  Phyllopertha horticola is not known to occur in California.

California Interceptions:  Phyllopertha horticola has been intercepted in an unidentified shipment and in the cargo area of a plane, both from Tennessee, in 2010 and 2011 (CDFA Pest and Damage Report Database, 2018).

The risk Phyllopertha horticola would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Phyllopertha horticola is distributed across a wide area, and it is likely that the climate present in much of California would suit this species. This beetle feeds on a wide variety of plants, and it would probably find suitable host plants in much of California.  This species is likely capable of establishing a widespread distribution in the state. Therefore, Phyllopertha horticola receives a High (3) in this category.

– 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: Phyllopertha horticola adults and larvae feed on living plant tissue, but they differ in that the larvae live underground and feed on roots of grasses and possibly (anecdotal information) other plants as well. The adults feed on leaves, fruit, and flowers of plants in at least two families, the Rosaceae and the Elaeagnaceae.  Therefore, it receives a Medium (2) in this category.

– 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: Adult Phyllopertha horticola   It is possible that larvae could be dispersed via movement of infested, potted plants, although evidence of such dispersal has not been found.  Therefore, it receives a Medium (2) in this category.

– 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: Phyllopertha horticola is a recognized pest, both in the larval as well as in the adult stage.  If this beetle became established in California, it could become a pest in agricultural situations, for example, in orchards, tree nurseries, or pastures. Therefore, it receives a Medium (2) in this category.

Economic Impact:  A, B

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:  2

– 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 Phyllopertha horticola became established in California, it could invade a variety of ecosystems, including prairie and grassland, where feeding by the larvae could disrupt native plant communities. This beetle could become a pest of trees and lawns in California, which could lead to treatment programs.  Therefore, it receives a High (3) in this category.

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

Environmental Impact:  A, D, E

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:

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 Phyllopertha horticola: Medium (12)

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: Phyllopertha horticola is not known to be present in California.  It 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:

7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (12)

Uncertainty:

There appears to be little uncertainty regarding the potential of Phyllopertha horticola to become an established pest in California.  The climate appears to be suitable, host plants are presumably widespread in the state, and this beetle is already a recognized pest in Europe.

Conclusion and Rating Justification:

Phyllopertha horticola is a serious pest of fruit trees, grass, and other plants in its native Europe, and it poses the same threat to California, where it is not yet known to occur.  For these reasons, an “A” rating is justified.

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References:

Aas, C. K., Olstad, T., Drageset, O.- M., Haukeland, S., Kleppestø, O., and Rukke, B. A.  2008.  A biological battle against the thousands of garden chafers (Phyllopertha horticola) that attract large numbers of gulls (Larus sp.) during the summer season at Rygge Air Station, Norway.  International Bird Strike Committee.  Accessed February 2, 2018:
http://www.int-birdstrike.org/Brasil_Papers/IBSC28%20WP15.pdf

Agricultural Research Service.  1957.  Insects not known to occur in the United States.  Cooperative Economic Insect Report 7:1-67.

CDFA Pest and Damage Report Database.  2018.  Phyllopertha horticola.  Plant Health and Pest Prevention Services. CA Department of Food and Agriculture.  Accessed February 2, 2018: https://pdr.cdfa.ca.gov/PDR/pdrmainmenu.aspx

Hann, P., Trska, C., Wechselberger, K. F., Eitzinger, J., and Kromp, B.  2015.  Phyllopertha horticola (Coleoptera: Scarabaeidae) larvae in eastern Austrian mountainous grasslands and the associated damage risk related to soil, topography and management.  SpringerPlus 4:139: 1-15.

Hill, D. S.  1987.  Agricultural Insect Pests of Temperate Regions and Their Control.  Cambridge University Press, New York, NY

Jackson, T. A.  2006.  Scarabs as pests: A continuing problem.  Coleopterists Society Monograph 5:102-119.

Mabbett, T.  2009.  Chafer grub, the pre-eminent insect pest of UK turf.  Greenkeeper International, May, 2009: 21-23.

Pernfuss, B., Zelger, R., Kron-Morelli, R., and Strasser, H.  2005.  Control of the garden chafer Phyllopertha horticola with GranMet-P, a new product made of Metarhizium anisopliae.  Insect Pathogens and Insect Parasitic Nematodes: Melolontha.  International Organization for Biological and Integrated Control of Noxious Animals and Plants, West Palearctic Regional Section Bulletin 28:9-12.

Petrova, V., Jankevica, L., and Samsone, I.  2013.  Species of phytophagous insects associated with strawberries in Latvia.  Proceedings of the Latvian Academy of Sciences, Section B, 67:124-129.

Ruther, J. and Mayer, C. J.  2005.  Response of garden chafer, Phyllopertha horticola, to plant volatiles: from screening to application.  Entomologia Experimentalis et Applicata 115:51–59.

Stalažs, A.  2015.  Review of sea buckthorn pests in Latvia.  p. 88 in Sanna, K. and Ekaterina, P. (eds.), Producing Sea Buckthorn of High Quality, Proceedings of the 3^rd European Workshop on Sea Buckthorn.  Natural Resources Institute Finland, Helsinki, Finland.

Symbiota Collections of Arthropods Network.  Accessed February 2, 2018: http://scan1.acis.ufl.edu

 

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Author:

Kyle Beucke, 1220 N Street, Room 221, Sacramento, CA, 95814, 916-403-6741; plant.health[@]cdfa.ca.gov.

Responsible Party:

Jason Leathers, 2800 Gateway Oaks, Sacramento CA 95833, (916) 654-1211, plant.health[@]cdfa.ca.gov

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Comment Period:* CLOSED

7/3/18 – 8/17/18

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*NOTE:

You must be registered and logged in to post a comment.  If you have registered and have not received the registration confirmation, please contact us at plant.health[@]cdfa.ca.gov.

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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.]

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♦  Comments may not be posted if they:

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Pest Rating: A

 

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Posted by ls 

California Pest Rating for

Ambrosia Beetle | Euwallacea similis (Ferrari)

Coleoptera: Curculionidae: Scolytinae

Pest Rating: A

 

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PEST RATING PROFILE

Initiating Event:

Euwallacea similis is currently Q-rated.  A permanent pest rating proposal is required to support an official pest rating.

History & Status:

Background:  Adult female Euwallacea similis measure approximately 2.5 mm in length.  Males are smaller, approximately 1.8 mm long.  Body color is reddish-brown (Kalshoven, 1964).  Like other ambrosia beetles, this species excavates galleries in wood.  Ambrosia fungus becomes established in these galleries and provides the primary food source for the larvae.  This beetle is common in stressed and dead (including cut) trees in the tropics; it is not known to attack healthy trees (Browne, 1961; CABI, 2018; Kalshoven, 1964; Maiti and Saha, 1986).  Some ambrosia beetles directly damage cut timber via tunneling behavior and stain the wood with the ambrosia fungus.  Browne (1961) reported E. similis to attack cut trees, and Sittichaya and Beaver (2009) reported damage to sawn rubber tree wood.  Reported host plants of E. similis include 62 genera in 29 families (Kalshoven, 1964; Maiti and Saha, 1986; Wood and Bright, 1992).

Worldwide Distribution:  Ambrosia beetles are easily introduced to new localities via movement of infested wood.  This is likely the reason that the native distribution of E. similis is uncertain.  However, this beetle is thought to be native to Asia and the Pacific from Pakistan to the Solomon Islands (CABI, 2017).  Countries included in the presumed native distribution are Australia, Bangladesh, Bhutan, Cambodia, China, India, Indonesia, Japan, Malaysia, Myanmar, Nepal, Pakistan, Papua New Guinea, Philippines, Singapore, Sri Lanka, Taiwan, Thailand, and Vietnam (CABI, 2017; Mathew et al., 2005; Rabaglia et al., 2006; Schedle, 1968).  This beetle has been introduced to Cameroon, Egypt, Jordan, Kenya, Mauritania, Mauritius, Pacific Islands (including Christmas Island, Cocos Island, Fiji, French Polynesia, Guam, Kiribati, Marshall Islands, Federated States of Micronesia, New Caledonia, Northern Mariana Islands, Palau, and Samoa), Seychelles, South Africa, Tanzania, and the United States (Florida, Mississippi, and Texas) (Atkinson, 2018; CABI, 2017; K. Fairbanks, pers. comm.; Halbert, 2012; Halbert, 2014; Symbiota Collections of Arthropods Network).

Official Control: Euwallacea similis is a Controlled Pest in the Republic of Korea (Food and Agriculture Organization of the United Nations, 2016).

California Distribution:  Euwallacea similis is not known to occur in California (Symbiota Collections of Arthropods Network).

California Interceptions:  Euwallacea similis was intercepted on Limnophila chinensis cuttings from Hawaii in 2004 (CDFA Pest and Damage Report Database, 2018).

The risk Euwallacea similis would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Euwallacea similis is apparently restricted to tropical and subtropical areas, so climate could limit the distribution of this species in California. This beetle has been reported to utilize numerous species of trees in at least 29 families.  Most or all of California has trees from many of these families (Calflora, 2018).  Fungus, which is the food of all life stages of similis, is carried by the adult female and would therefore be introduced to any new places this beetle inhabits.  Therefore, Euwallacea similis receives a Medium (2) in this category.

– 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: Euwallacea similis feeds on fungi in galleries that are excavated in trees. Trees in at least 29 families are used by this beetle.  A broad host range is typical of ambrosia beetles.  Therefore, it receives a High (3) in this category.

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Reproductive and Dispersal Potential: There is evidence suggesting that ambrosia beetles that have brother-sister mating, which is the case with similis, have an enhanced ability to disperse and colonize new areas.  A single female, whether fertilized or not, can start a new population.  If she is unfertilized, she can produce sons from unfertilized eggs and mate with them.  Euwallacea similis flies (specimens have been caught with funnel traps).  Rapid, long-distance dispersal could result from movement of infested firewood (Wood, 2007).  Therefore, it receives a High (3) in this category.

– 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: Euwallacea similis is reported to only attack stressed, dead, or dying trees; it is not reported to attack healthy trees (CABI, Kalshoven, 1964).  However, this species is reported to attack sawn timber, and it could therefore damage cut timber through gallery excavation and staining caused by the ambrosia fungus (Sittichaya and Beaver, 2009).  Avoidance of this damage could require a change in normal cultural practices.  There is also the chance that this beetle could vector a plant-pathogenic fungus to economically-important trees.  Therefore, it receives a Medium  (2) in this category.

Economic Impact:  D, 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.

Economic Impact Score:  2

– 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: Euwallacea similis has not been reported to have an environmental impact anywhere it has been introduced. This does not mean that this beetle is not capable of having an impact in California.  Ambrosia beetles are less constrained than other scolytines in their host plant choices, and this makes it more difficult to predict what trees might be attacked in a new environment.  Therefore, it receives a High (3) in this category.

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

Environmental Impact: A, B

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:

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 Euwallacea similis: High (13)

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: Euwallacea similis is not known to be present in California.  It 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 (13)

Uncertainty:

There is a lack of evidence that E. similis is having economic or environmental impacts in the United States, where this species is apparently established in Florida, Mississippi, and Texas.  Therefore, the possible economic impacts considered in this proposal may be pessimistic.  There do not appear to be any reports of E. similis having an environmental impact anywhere in the world.  However, this may simply reflect a lack of research rather than an actual lack of impact.  Ambrosia beetles depend on ambrosia fungi, which have their own environmental requirements, including temperature and humidity (Kirisits, 2007).  The climate of California may not be suitable for these fungi, which may preclude the establishment of E. similis.  Drought-stressed trees could be more susceptible to attack by ambrosia beetles, including E. similis.  Therefore, an increase in drought resulting from climate change could make California’s trees more vulnerable to this and other ambrosia beetles.  There is also uncertainty regarding the possibility of E. similis (and other ambrosia beetles) interacting with plant-pathogenic fungal species that are already present in California.

Conclusion and Rating Justification:

There is no evidence that Euwallacea similis causes economic or environmental damage anywhere it is known to have been introduced.  However, it seems that a cautious approach is best with possible forest pests.  The behavior of this beetle may be different in the environments of California.  At least one introduced ambrosia beetle, Xyleborus glabratus, has become a serious pest species in the southeastern United States; it is having a significant impact on the environment as well as threatening the avocado industry.  The fungus symbiosis with ambrosia beetles raises special concerns, because the beetle could bring with it possibly pathogenic fungi new to California, or it could develop a new relationship with fungi already here.  For these reasons, an “A” rating is justified.

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References:

Atkinson, T. H.  2018.  Bark and ambrosia beetles.  Accessed: February 16, 2018: http://www.barkbeetles.info/about.php

Browne, F. G.  1961.  The biology of Malayan Scolytidae and Platypodidae.  Malayan Forest Records 22:1-255.

CABI.  2017.  Invasive Species Compendium.  Accessed February 2, 2018: www.cabi.org/isc

Calflora.  2018.  Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals.  Accessed February 6, 2018: http://www.calflora.org

CDFA Pest and Damage Report Database.  2018.  Euwallacea similis.  Plant Health and Pest Prevention Services. CA Department of Food and Agriculture.  Accessed April 25, 2018: https://pdr.cdfa.ca.gov/PDR/pdrmainmenu.aspx

Food and Agriculture Organization of the United Nations.  2016.  List of quarantine pests in Korea.  Accessed February 2, 2018: https://www.ippc.int/en/countries/republic-of-korea/reportingobligation/2014/04/the-list-of-quarantine-pest-2013/

Halbert, S. E.  2012.  Entomology section.  Tri-ology 51:7-9.

Halbert, S. E.  2014.  Entomology section.  Tri-ology 53: 6-9.

Kalshoven, L. G. E.  1964.  The occurrence of Xyleborus perforans (Woll.) and X. similis in Java (Coleoptera, Scolytidae).  Beaufortia 11:131-142.

Kirisits, T.  2007.  Fungal associates of European bark beetles with special emphasis on the ophiostomatoid fungi.  pp. 181-235 in Lieutier, F., Day, K.R., Battisti, A., Grégoire, J-C., and H.F. Evans, H.F. (eds.), Bark and wood boring insects in living trees in Europe, a synthesis.  Springer.

Maiti, P. K. and Saha, N.  1986.  A contribution to the knowledge of the bark and timber beetles (Scolytidae: Coleoptera) of the islands of Andaman and Nicobar, India.  Records of the Zoological Survey of India Miscellaneous Publication Occasional Paper 86:1-182.

Mathew, G., Shamsudeen, R. S. M., and Chandran, R.  2005.  Insect fauna of Peechi-Vazhani Wildlife Sanctuary, Kerala, India.  ZOO’s Print Journal 20:1955-1960.

Rabaglia, R. J., Dole, S. A., and Cognato, A. I.  2006.  Review of American Xyleborina (Coleoptera: Curculionidae: Scolytinae) occurring north of Mexico, with an illustrated key.  Annals of the Entomological Society of America 99:1034-1056.

Schedl, K. E.  1968.  On some Scolytidae and Platypodidae of economic importance from the territory of Papua and New Guinea.  Pacific Insects 10:261-270.

Sittichaya, W. and Beaver, R.  2009.  Rubberwood-destroying beetles in the eastern and gulf areas of Thailand (Coleoptera: Bostrichidae, Curculionidae: Scolytinae and Platypodinae).  Songklanakarin Journal of Science and Technology 31:381-387.

Symbiota Collections of Arthropods Network.  Accessed February 16, 2018: http://scan1.acis.ufl.edu

Wood, S. L.  2007.  Bark and ambrosia beetles of South America.  Brigham Young University, Provo, Utah.

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Author:

Kyle Beucke, 1220 N Street, Room 221, Sacramento, CA, 95814, 916-403-6741; plant.health[@]cdfa.ca.gov.

Responsible Party:

Jason Leathers, 2800 Gateway Oaks, Sacramento CA 95833, (916) 654-1211, plant.health[@]cdfa.ca.gov

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Comment Period:* CLOSED

6/28/18 – 8/12/18

---

*NOTE:

You must be registered and logged in to post a comment.  If you have registered and have not received the registration confirmation, please contact us at 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

 

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Posted by ls