Category Archives: Gastropoda

Gastropoda, Ratings, Snails and Slugs

Banded Wood Snail | Cepaea nemoralis

November 7, 2017 Dean Kelch

California Pest Rating for

Banded Wood Snail | Cepaea nemoralis

Gastropoda: Helicidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Cepaea nemoralis is frequently intercepted by CDFA. A pest rating proposal is required to support its permanent pest rating.

History & Status:

Background: Cepaea nemoralis, known as the banded wood snail, is the most common species of land snail in Europe and has been introduced to North America. This snail is commonly found in urban areas, where it inhabits gardens and abandoned lots. They feed on dead and living plant material, carrion, fungi, moss, and insects¹.

Cepaea nemoralis has a yellow, pink, or brown shell. The shell contains five dark bands. Banded wood snails are hermaphrodites, but cross fertilization occurs (each snail fertilizes the other). They often mate multiple times prior to egg-laying and can store sperm for up to 15 months. Eggs are buried in moist soil, hatching after about three weeks. The snails reach maturity in four years and may live as long as five to nine years^{1, 4}.

Worldwide Distribution: Banded wood snails are distributed throughout much of Europe, extending to Poland. This snail was introduced into North America during the nineteenth century, and it is currently found in Virginia, New York, Ontario, and Massachusetts^{1, 2}.

Official Control: Banded wood snail is listed as a harmful organism in Canada, Israel, Japan, and Taiwan⁶.

California Distribution: Banded wood snails have never been found in the environment of California.

California Interceptions: Between January 2000 and August 2017, banded wood snails have been intercepted 20 times. These interceptions include border station inspections and high risk pest exclusion activities.

The risk Cepaea nemoralis (Banded wood snail) would pose to California is evaluated below.

Consequences of Introduction:

Climate/Host Interaction: Banded wood snails can feed on a variety of live and dead plants and dead animals and insects, including remains of ants, beetles, spiders, mites, springtails, and aphids. Banded wood snails may establish in larger, but limited, warm agricultural and metropolitan areas of California. It receives a Medium (2) 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: Banded wood snails are highly polyphagous and are known to feed on a wide variety of live and dead plants and animals. 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: Banded wood snails are obligately outcrossing hermaphrodites, with both individuals exchanging sperm during mating, and both individuals able to lay eggs afterward. On average, they lay 30-80 eggs that hatch in 15-20 days. Breeding takes place from April through October. The snail’s foot is used to create a cavity in the soil where the eggs are deposited^{1, 4}. 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: The banded wood snail is not expected to lower crop yields. It could reduce the value of nursery stock by disfiguring plants with its presence and increase crop production costs in nurseries and orchards. The banded wood snail is a potential vector of Angiostrongylus vasorum, the French heartworm (a disease of wild and domestic canids)³. It receives a High (3) in this category. Economic Impact: B, C, E: Environmental Score: 3

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

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 introduced, the banded wood snail is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It might trigger new chemical treatments in orchards and nurseries and by residents who find infested plants unsightly. It is not expected to significantly impact cultural practices, home/urban gardening, or ornamental plantings. It receives a Medium (2) in this category.

Environmental Impact: A, D: Environmental Impact: Score: 2

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.

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 Cepaea nemoralis(Banded wood snails): High (13)**

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

Post Entry Distribution and Survey Information: The banded wood snail has never been found in the environment in California 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.

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

Final Score:

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

Uncertainty:

Banded wood snails are commonly intercepted. There have been no formal surveys for this snail in the state. It is therefore possible that it could be present in some locations in California.

Conclusion and Rating Justification:

Banded wood snail is not known to occur in California and might cause significant economic and environmental impacts if it were to become established here. Currently, an “A” rating is justified.

References:

Animal Diversity Web. Accessed September 7, 2017. http://animaldiversity.org/accounts/Cepaea_nemoralis/

2. Encyclopedia of Life. Accessed September 7, 2017.
http://eol.org/pages/449909/details#overview

3. G.A. Conboy. 2000. Canine Angiostrongylosis (French Heartworm). Accessed September 7, 2017.
http://www.ivis.org/advances/Parasit_Bowman/conboy_angiostrongylosis/ivis.pdf

4. Maggie Whitson. 2005. Journal of the Kentucky Academy of Science, 66(2):82-88. Accessed September 7, 2017.
http://stoppinginvasives.com/dotAsset/e2bbc1b0-81c5-42b1-b9e4-8123952c6c02.pdf

5. 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

6. USDA phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). Accessed September 7, 2017.
https://pcit.aphis.usda.gov/pcit/

Author:

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

Responsible Party:

Jason Leathers; California Department of Food and Agriculture; 1220 N Street, Sacramento, CA 95814; Tel. (916) 654-1211; plant.health[@]cdfa.ca.gov.

Pest Rating: A

Posted by dk

Gastropoda, Snails and Slugs

Chinese Slug | Meghimatium bilineatum (Benson)

June 21, 2016 Jason Leathers

California Pest Rating for

Chinese Slug | Meghimatium bilineatum (Benson)

Gastropoda: Philomycidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Meghimatium bilineatum has been intercepted by CDFA’s high risk programs, border stations, and dog teams and presently has a temporary rating of “Q”. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Meghimatium bilineatum is a terrestrial slug that lives in humid environments beneath plants and emerges to forage after rainfall¹. It is also found on cultivated land, landscaped urban areas, smooth-barked live trees, rocks, and under dead logs². Like other slugs Meghimatium bilineatum is presumably polyphagous on a wide variety of living and decaying plants. The slug may be transported long distances on nursery stock.

Worldwide Distribution: Meghimatium bilineatum is native to the mid and lower Yangtse basin of China¹. From there it has spread to Taiwan, Japan, Hawaii, Java, and Russia². Interceptions by CDFA on consignments from Florida and Ecuador indicate that it could be more widespread.

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

California Distribution: Meghimatium bilineatum has never been found in the environment of California.

California Interceptions: CDFA has intercepted Meghimatium bilineatum 16 times on nursery stock and ti leaves from Hawaii, Ecuador, and Florida.

The risk Meghimatium bilineatum would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Meghimatium bilineatum is a polyphagous terrestrial slug and is likely able to establish anywhere suitable moisture is available in California. 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: Meghimatium bilineatum is presumably polyphagous on a wide variety of living and decaying plants. 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: Females of Meghimatium bilineatum may live up to four years in the laboratory and produce an average of 932 eggs, indicating a high reproductive rate. The slugs may be transported long distances when infested nursery stock is moved. Meghimatium bilineatum 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: Meghimatium bilineatum does not appear to be documented as an agricultural pest and is therefore not expected to lower crop yields. However, slugs have the potential to significantly reduce the value of nursery stock by feeding on plants and contaminating them with their presence. The slugs are not expected to interfere with markets or change cultural practices. Meghimatium bilineatum has been documented as a vector of rat lungworm⁴. The slugs are not expected to injure animals or interfere with water supplies. Meghimatium bilineatum receives a Medium (2) in this category.

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

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Meghimatium bilineatum is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not expected to directly affect threatened or endangered species or disrupt critical habitats. It may trigger additional treatment programs in the nursery industry and by residents who find infested plants or garden unacceptable. It is not expected to significantly impact cultural practices, home/urban gardening, or ornamental plantings. Meghimatium bilineatum receives a Medium (2) in this category.

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

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Meghimatium bilineatum: 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: Meghimatium bilineatum 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 (13)

Uncertainty:

There have not been any recent comprehensive slug surveys in California. It is possible that Meghimatium bilineatum could be present in some localities.

Conclusion and Rating Justification:

Meghimatium bilineatum has never been found in the environment of California and may have significant economic and environmental impacts if it were to establish here. An “A” rating is justified.

References:

¹ Wiktor, Andrzej, Chen De-Niu, and Wu Ming. 2000. Stylommatophoran Slugs of China (Gastropoda: Pulmonata) – Prodromus. Folia Malacologica 8(1): 3-35. http://agro.icm.edu.pl/agro/element/bwmeta1.element.agro-e16e8da9-fe23-46f1-9334-cd9a90234311/c/FM08_1__2_1_.pdf

² Paustian, Megan. Terrestrial Slugs Web. http://terrslugs.lifedesks.org/pages/31161

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

⁴ Molet, T. 2014. CPHST Pest Datasheet for Meghimatium pictum. USDA-APHIS-PPQ-CPHST. https://caps.ceris.purdue.edu/webfm_send/2556

Responsible Party:

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

Pest Rating: A

Posted by ls

Gastropoda, Insects, Mites & Earthworms

A Semi-Slug | Parmarion martensi (Simroth)

March 9, 2016 Jason Leathers

California Pest Rating for

A Semi-Slug | Parmarion martensi (Simroth)

Gastropoda: Helicarionidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

Parmarion martensi has been intercepted by CDFA and presently has a temporary “Q” rating. A pest rating proposal is required to determine a permanent pest rating.

History & Status:

Background: Parmarion martensi is a terrestrial semi-slug that is polyphagous on a variety of living and decaying plant material. In Hawaii a survey found the semi-slug on: green plants: lettuce, fennel, sweet potato, banana, passion fruit, lemongrass, Heliconia; fallen fruit: avocado, guava, citrus, papaya, mango; under plastic or plastic-like materials: black plastic sheeting, tarps, drainpipes, plant pots; compost and trash cans; food preparation and sink areas: outdoor sinks, dishes, grills, a toothbrush; pet food; structures: decks, walkways, walls; palm trees; catchment tanks; ripe fruit: papaya; miscellaneous plant debris¹. Semi-slugs may be transported long distances when infested plants or plant parts are moved.

Worldwide Distribution: Parmarion martensi is presumably native to continental Southeast Asia¹. It has also been found in Sumatra, Java, Borneo, Japan, Taiwan, Samoa, and American Samoa¹. It was first found in Hawaii on the islands of O’ahu in 1996 and Hawai’i in 2004¹.

Official Control: Parmarion martensi is not known to be under official control in any other states or nations².

California Distribution: Parmarion martensi has never been found in the environment of California.

California Interceptions: Since March 2009 Parmarion martensi has been intercepted by CDFA’s high risk programs and dog teams 37 times on nursery stock and plant parts imported from Hawaii.

The risk Parmarion martensi would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Parmarion martensi is a polyphagous semi-slug and is likely able to establish anywhere suitable moisture is available in California. 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: Parmarion martensi is polyphagous on a wide variety of living and decaying plants. 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: Parmarion martensi produces large numbers egg masses¹ and may be transported long distances when infested nursery stock is moved. It 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: Parmarion martensi is an efficient vector of the parasitic nematode that causes rat lungworm disease in humans¹. The semi-slug often feeds on green plants such as lettuce, contaminating the produce with nematodes that can be present in tiny immature semi-slugs or slime. This could have significant impacts on California’s salad industry. Although the semi-slug is not known to be on any quarantine list, its presence in the state may affect markets for California produce if any of it were found to be contaminated with rat lungworm disease. This may lower crop yields if produce were unmarketable and increase crop production costs as growers ensure that fields are free from Parmarion martensi. The semi-slug receives a High (3) in this category.

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

Economic Impact Score: High (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: Parmarion martensi is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not expected to directly affect threatened or endangered species or disrupt critical habitats. The semi-slug is likely to trigger additional treatment programs in the nursery industry, by growers, and by residents who find contaminated produce unacceptable. As an efficient vector of the nematode that causes rat lungworm disease, Parmarion martensi has the potential to significantly impact home/urban gardening by sickening residents. The semi-slug receives a High (3) in this category.

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

Environmental Impact: 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: High (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 Parmarion martensi: 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: Parmarion martensi has never been found in the environment of 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:

There have been no recent surveys for semi-slugs in California. It is possible that some of them could have eluded inspections and made it into the state.

Conclusion and Rating Justification:

Parmarion martensi has never been found in California and is likely to have significant economic and environmental impacts if it were to establish here. An “A” rating is justified.

References:

¹ Hollingsworth, R.G., R. Kaneta, J.J. Sullivan, H.S. Bishop, Y. Qvarnstrom, A.J. da Silva, and D.G. Robinson. 2007. Distribution of Parmarion cf. martensi (Pulmonata: Helicarionidae); a new Semi-Slug Pest on Hawai’i island, and its potential as a Vector for Human Angiostrongyliasis. Pacific Science 61(4): 457-467.

² USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/