Conotrachelus nenuphar

Harris, 1841

Plum Curculio

The is a native North American weevil and economically significant pest of stone and pome fruits. It has been documented as a fruit pest since the 18th century and remains a primary challenge for orchard production east of the Rocky Mountains. The exhibits geographic variation in voltinism, with in northern regions and multivoltine populations in the south.

Conotrachelus nenuphar by (c) Clemson University, some rights reserved (CC BY). Used under a CC-BY license.

Conotrachelus nenuphar by (c) Justin Williams, some rights reserved (CC BY), uploaded by Justin Williams. Used under a CC-BY license.

Conotrachelus nenuphar by (c) Paul Marek, some rights reserved (CC BY), uploaded by Paul Marek. Used under a CC-BY license.

Pronunciation

How to pronounce Conotrachelus nenuphar: /ˌkoʊnoʊˈtrækələs ˈnɛnʊfɑr/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

A small true weevil with the characteristic elongated snout (rostrum) typical of Curculionidae. Specific diagnostic features distinguishing it from other Conotrachelus are not provided in available sources.

Images

Habitat

Agricultural including orchards of stone fruits (Prunus spp.), pome fruits (Malus, Pyrus), and blueberry. Overwinters primarily in woodland areas adjacent to orchards, with spring to fruit-growing regions.

Distribution

to North America east of the Rocky Mountains. Documented in Canada (Manitoba, New Brunswick, Newfoundland, Nova Scotia, Ontario, Prince Edward Island, Quebec) and the United States (Alabama, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Hampshire, New Jersey, New York, North Carolina, North Dakota, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, West Virginia, Wisconsin).

Seasonality

emerge from sites in spring and disperse to orchards. Activity shifts from primarily before fruit set to as fruits become available for oviposition. Summer emerges in August in northern regions. Northern undergo obligate winter reproductive .

Diet

Oligophagous, feeding on rosaceous including stone fruits (peach, apricot, nectarine, plum), pome fruits (apple, pear), and blueberry. feed on fruit exterior; larvae feed internally on developing fruit.

Host Associations

Prunus persica - peach
Prunus armeniaca - apricot
Prunus spp. - stone fruits
Malus pumila - apple
Pyrus communis - pear
Vaccinium - blueberry in some regions
Prunus mume - first reported

Life Cycle

Complete . oviposit into developing fruit, creating crescent-shaped scars. Larvae develop internally, feeding on fruit flesh. Mature larvae exit dropped fruit and pupate in soil. to adult requires approximately one month. Northern strain is with obligate winter ; southern strain is multivoltine. Full-grown larvae in dropped fruit in June ("June drop") enter soil to pupate.

Behavior

exhibit cyclic movement within trees in spring. Before fruit set, adults are primarily ; activity extends to daytime when fruits become available for oviposition. Summer adults feed on remaining fruit through fall before dispersing to sites. Protein immunomarking studies indicate adults can be tracked without behavioral disruption. Females climb significantly greater distances than males.

Human Relevance

Major economic pest of fruit production causing three damage types: feeding scars, oviposition scars on fruit exterior, and internal larval feeding leading to premature fruit abortion (June drop). Near-complete crop loss can occur if left untreated. Subject of extensive research including discovery, trap tree methods, and applications. Pyriproxyfen can artificially terminate reproductive in northern strain for laboratory rearing.

More Details

Voltinism Variation

Geographic strains differ in : northern are with obligate winter reproductive , while southern populations are multivoltine.

Historical Significance

First described damage to domesticated fruit dates to the 18th century. The last comprehensive review prior to 2021 was published in 1912 (The ).

Management Challenges

Control is complicated by larval development inside fruit, unpredictable , lack of effective commercially available biocontrol agents, and absence of convenient reliable monitoring techniques for spray timing.