Description

Taxonomy

Kingdom	Phylum	Class	Order	Family	Genus
Animalia	Hexapoda	Insecta	Coleoptera	Curclionidae	Nanophyes

Synonyms

Nanophyes lythri; Nanophyes leucozomius; Nanophyes transversus; Nanophyes vittatus

Invasion History

Chesapeake Bay Status

First Record	Population	Range	Introduction	Residency	Source Region	Native Region	Vectors
1995	Established	Unknown	Introduced	Unconfirmed	Europe	Eurasia	Biocontrol

History of Spread

Nanophyes marmoratus, a weevil native to Eurasia, from Europe to western Siberia, is exclusively associated with Lythrum salicaria (Purple Loosestrife), whose buds, flowers and seeds, it feeds on (Batra et al. 1986; Hoffmann 1958). This insect was identified as a candidate for biological control of L. salicaria in North America. Feeding experiments indicated no feeding on 8 other species, in the presence of L. salicaria, and no completion of the life cycle, except with L. salicaria (Blossey and Schroeder 1995). Nanophyes marmoratus was considered to have a high probability of establishment, but a lower effectiveness than other potential biocontrol species. However, Blossey (1995a) considered that having a combination of species attacking all parts of the plant could increase the overall effectivness of a biocontrol program.

Nanophyes marmoratus was certified for import and release in the U.S. in 1994 by the Technical Advisory Group for Introduction of biological Control Agents of Weeds in 1994. Stocks of the weevil were maintained at Beltsville, and subsequently distributed. N. marmoratus has been released in at least 7 states (Skinner 1996; Blossey 1997).

Nanophyes marmoratus has been released in the Chesapeake Bay watershed, in 6 counties along the Susquehanna River in PA, from 1995 onward (Moser 2002). However, to our knowledge, it has not yet been released or collected in tidal waters in the Chesapeake Bay region.

References- Batra et al. 1986; Blossey 1995a; Blossey 1997; Blossey and Schroeder 1995; Hoffmann 1958; Moser 2002; Skinner 1996

Invasion Comments

Ecology

Environmental Tolerances

	For Survival		For Reproduction
	Minimum	Maximum	Minimum	Maximum
Temperature (ºC)
Salinity (‰)	0.0		0.0
Oxygen
pH
	Salinity Range	fresh-oligo

Age and Growth

	Male	Female
Minimum Adult Size (mm)	1.0	1.0
Typical Adult Size (mm)	1.4	1.4
Maximum Adult Size (mm)	1.7	1.7
Maximum Longevity (yrs)	1.0	1.0
Typical Longevity (yrs	1.0	1.0

Reproduction

	Start	Peak	End
Reproductive Season
Typical Number of Young Per Reproductive Event
Sexuality Mode(s)
Mode(s) of Asexual Reproduction
Fertilization Type(s)
More than One Reproduction Event per Year
Reproductive Startegy
Egg/Seed Form

Impacts

Economic Impacts in Chesapeake Bay

Nanophyes marmoratus, a weevil which feeds on the flowers and seeds of Lythrum salicaria (Purple Loosestrife) was selected as a biocontrol organism for this invasive plant, based on its high degree of specificity in feeding (Blossey and Schroeder 1995). It has been released in 6 PA counties bordering the Susquehanna River in PA. (Moser 2002), but we have no record of it having been released or collected in tidal Chesapeake Bay wetlands. In the Susquehanna watershed, so far, herbicide and manual removal appear to have been more effective than biocontrol (Moser 2002).

References- Blossey and Schroeder 1995; Moser 2002

Economic Impacts Outside of Chesapeake Bay

Ecological Impacts on Chesapeake Native Species

Nanophyes marmoratus, a weevil which feeds on the flowers and seeds of Lythrum salicaria (Purple Loosestrife) was selected as a biocontrol organism, based on its high degree of specificity in feeding (Blossey and Schroeder 1995). It has been released in 6 PA counties bordering the Susquehanna River, but we have no record of it having been released or collected in tidal wetlands of Chesapeake Bay. This insect had no significant feeding on native plants in experiments, so any impacts would be as a consequence of reducing invasive L. salicaria populations.

References- Blossey and Schroeder 1995

Ecological Impacts on Other Chesapeake Non-Native Species

Nanophyes marmoratus, a weevil which feeds on the flowers and seeds of Lythrum salicaria (Purple Loosestrife) was selected as a biocontrol organism, based on its high degree of specificity in feeding. Feeding by N. marmoratus on buds causes abortion of flowers and seeds (Blossey and Schroeder 1995). It has been released in 6 PA counties bordering the Susquehanna River, but we have no record of it having been released or collected in tidal wetlands of Chesapeake Bay. In the Susquehanna watershed, so far, herbicide and manual removal appear to have been more effective than biocontrol (Moser 2002).

References- Blossey 1997; Blossey and Schroeder 1995; Moser 2002

References

Batra, S. W. T.; Schroeder, D.; Boldt, P. E.; Mendl, W. (1986) Insects associated with purple loosestrife (Lythrum salicaria L.) in Europe, Proceedings of the Entomological Society of Washington 88: 748-759

Blossey, Bernd (1995) A comparison of various approaches for evaluating potential biological control agents using insects on Lythrum salicaria, Biological Control 5: 113-122

1998 Purple Loosestrife Project Page. http://www.dnr.cornell.edu/bcontrol/purple.htm

Blossey, Bernd; Schroeder, Dieter (1995) Host specificity of three biological weed control agents attacking flowers and seeds of Lythrum salicaria (purple loosestrife), Biological Control 5: 47-53

Hoffmann, Adolphe (1958) Coleopteres Curculionides (Troisième Partie), , Paris. Pp.

Moser, Fredrika C. (editor) (2002) Invasive species in the Chesapeake Bay watershed: A workshop to develop regional invasive species management strategies., , College Park MD; Washington DC. Pp.

Skinner, Luke (1996) Biological control of purple loosestrife- a new control method for a tough wetland invader, Aquatic Nuisance Species Digest 1: 43-45

Nanophyes marmoratus

Invertebrates