Little Leaf Notcher Weevil: Essential Facts and Tips

The Little Leaf Notcher Weevil (Artipus floridanus) is a secondary pest that targets citrus plants, primarily in Florida and the Caribbean region. Belonging to the Curculionidae family, which consists of weevils and snout beetles, this small beetle has gained attention due to its impact on citrus crops.

Adult Little Leaf Notcher Weevils feed on the leaves of citrus trees, causing notches and damage to the foliage. The larvae of these weevils, known as citrus root weevils, also pose a threat by feeding on the tree roots. As a result, it’s crucial for citrus growers to be aware of this pest’s appearance, life cycle, and potential control methods.

In this article, we’ll discuss everything you need to know about the Little Leaf Notcher Weevil. From identifying its characteristics to understanding how it affects citrus plants and exploring possible prevention and control techniques, you’ll be well-equipped to deal with this pest in your citrus groves.

Little Leaf Notcher Weevil Overview

Appearance

The Little Leaf Notcher Weevil, also known as Artipus floridanus, is a beetle from the family Curculionidae, which includes weevils and snout beetles¹. They have a distinctive elongated snout, and their body is usually dark brown or black in color.

Habitat

These insects primarily feed on citrus plants². They are a secondary pest of citrus in Florida and the Caribbean region. As adults, they notch the margins of leaves on young, tender shoots³.

Distribution

Little Leaf Notcher Weevils are native to Florida, and can also be found throughout the Caribbean region². They are considered one of several species of citrus root weevils, such as the Diaprepes Root Weevil⁴.

Life Cycle and Behavior

Eggs

Little Leaf Notcher Weevil’s life cycle begins with the female laying egg masses on the host plant’s leaves. A single female can lay:

• Hundreds of eggs
• Eggs are small and white

This ensures a high number of offspring and overlapping generations.

Larval Stage

After hatching, the larvae start feeding on the host plant:

• They feed on leaves, roots, or the trunk
• Can be found in soil or on the plant surface
• Develop a mutual relationship with ants

This stage lasts for several weeks before advancing to the pupae stage.

Pupae

The pupae stage is a transitional period:

• Takes place in the soil
• Pupae are white and immobile

During this phase, the weevil undergoes a significant transformation before emerging as an adult.

Adults

Adult Little Leaf Notcher Weevils exhibit distinct features:

• Mottled gray in color
• Beetle-like appearance
• Presence of a snout

Adults primarily engage in mating and seeking host plants for laying eggs.

In conclusion, understanding the specific behaviors and stages of the Little Leaf Notcher Weevil is essential to effectively manage and control their population.

Feeding Damage and Host Plants

Citrus Trees

Little Leaf Notcher Weevils can cause significant damage to citrus tree foliage, as they were first described feeding on orange tree foliage in south Florida in 1879¹. Citrus species like orange, grapefruit, and lime are among their preferred hosts¹.

Grapefruit

The Little Leaf Notcher Weevil enjoys feeding on grapefruit trees as well¹. Their feeding can cause damage to leaves and affect the overall health of the tree.

Limes

Lime trees are not spared from the Little Leaf Notcher Weevil’s appetite¹. As with other citrus trees, the weevil’s feeding can lead to leaf damage and potential reduction in fruit production.

Avocado

In addition to citrus trees, the Little Leaf Notcher Weevil has a wide host range, including avocado trees. Although they may not cause as much damage as with citrus trees, they can still negatively affect avocado trees’ health.

Mango

Mangoes are another tree that can serve as a host for the Little Leaf Notcher Weevil. They may cause damage to leaves, impacting the tree’s overall health and potentially reducing fruit production.

Hibiscus

The Little Leaf Notcher Weevil is also known to feed on ornamentals like hibiscus². As with other host plants, damage to leaves may occur.

Other Host Plants

Artipus floridanus, or the Little Leaf Notcher Weevil, has a wide host range that includes at least 150 different plant species¹. Some other examples of non-crop hosts that are important to the weevil include dune plants¹.

Comparison Table:

Impact on Citrus Industry

Florida Citrus Pest Management Guide

The Little Leaf Notcher Weevil, or Artipus floridanus, is a secondary pest affecting citrus trees in Florida and the Caribbean region¹. They belong to the family Curculionidae, and are considered citrus root weevils alongside species like Diaprepes root weevil¹.

While their distribution is predominantly within Florida, they have the potential to infest citrus trees in other parts of the U.S. The weevil’s impact is felt in the citrus industry due to the noticeable notching of leaf margins by adults². The damage inflicted on young foliage depends on the weevil species, their abundance, and the availability of food².

These citrus root weevils can infest a variety of plants, such as lime, rose, and ornamentals³. Due to their habitat preferences, orchards need to employ pest management strategies to curtail the infestation. Effective alternatives include:

• Monitoring adult weevil populations
• Applying insecticides

However, it is essential to adopt eco-friendly and sustainable pest management practices to protect the citrus industry. Using excessive insecticides can harm the environment and disrupt the natural predator-prey balance.

Control Methods and Management

Cultural Control

Cultural control methods play a crucial role in managing the Little Leaf Notcher Weevil. One effective strategy is practicing proper sanitation in the affected area, which means removing potential breeding sites, such as debris, dead leaves, and fallen fruits. By implementing these techniques, you can minimize the growth of weevil populations in your garden.

Mechanical Control

Mechanical control of Little Leaf Notcher Weevil focuses on manual removal. For instance, the Sri Lankan Weevil drops to the ground and pretends to be dead when disturbed, making hand-picking a viable option. Additionally, shaking a branch over a container like an umbrella can help in collecting multiple weevils at once.

Chemical Control

Chemical control methods are also available, but should be used with caution and only after other methods have been exhausted. Chemical products such as systemic insecticides can be used to protect plants from weevils, but always follow label instructions and use them sparingly, as the chemicals can be harmful to beneficial insects.

Remember to always have a balanced approach when trying to control the Little Leaf Notcher Weevil. Combine cultural, mechanical, and chemical control methods if necessary, and always consider the environmental impact before making decisions.

Biological Control Agents

Nematodes

• Steinernema carpocapsae: A parasitic nematode effective against small larvae of the little leaf notcher weevil¹
• Heterorhabditis bacteriophora: Another parasitic nematode used against the weevil’s young larvae²
• Steinernema riobravis: A third species of nematode effective against the pest³

Nematodes have the following features:

• Soil-dwelling microscopic worms
• Attack underground life stages of the weevil
• Can be applied as a foliar spray on affected plants

Beauveria Bassiana

• A fungus that works as a biocontrol agent⁴
• Infects the weevil through direct contact and ingestion

Characteristics of Beauveria Bassiana:

• Can be applied as a foliar spray
• Pathogen to the little leaf notcher weevil
• Can be used as a part of an integrated pest management program

Soaps and Oils

Soaps and oils can help control the little leaf notcher weevil populations:

• Insecticidal soaps work by disrupting the insect’s cuticle
• Horticultural oils (such as neem oil) can smother the insect and prevent them from breathing

Pros of using soaps and oils:

• Environmentally friendly
• Less harmful to beneficial insects

Cons of using soaps and oils:

• Require direct contact with the insect to be effective
• May need to be reapplied after rain

Comparison of Control Methods

Bug Control Recommendation Tool

What type of pest are you dealing with?

Ants Cockroaches Termites Mosquitoes Bed Bugs Spiders Other

How severe is the infestation?

A few sightings Several sightings weekly Several sightings daily Large numbers, causing damage Unknown but suspect a large number

Do you require child/pet/garden safe treatments (organic)?

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Are you willing to monitor and maintain the treatment yourself?

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Closely Related Weevil Species

In this section, we will discuss three closely related weevil species: Diaprepes abbreviatus, Pachnaeus litus, and Pachnaeus opalus. These species are often found alongside the Little Leaf Notcher Weevil (Artipus floridanus).

Diaprepes Abbreviatus

Diaprepes abbreviatus, commonly known as the Diaprepes root weevil, is one of the most injurious weevils affecting citrus plants. Adults have prominent blue-green coloration and can cause significant damage to citrus roots. Some key features include:

• Behavior: Active during the day, feeds on citrus leaves and lays eggs on foliage.
• Range: Mostly found in Central Florida, Caribbean, and other tropical regions.

Pachnaeus Litus

Pachnaeus litus, also known as the blue-green citrus root weevil, is another species that shares similar habitats with the Little Leaf Notcher. Key characteristics include:

• Behavior: Primarily nocturnal, feeds on young citrus leaves.
• Range: Prefers subtropical regions, overlaps with other weevil species in Central Florida.

Pachnaeus Opalus

Pachnaeus opalus is closely related to Pachnaeus litus and shares similar behavioral characteristics. Some important features of this species are:

• Behavior: Active during the night, feeding on citrus plant roots.
• Range: Found in subtropical areas, overlaps with Pachnaeus litus in Central Florida.

These weevil species cause varying degrees of damage to citrus plants, with Diaprepes abbreviatus being particularly harmful. Understanding their behavior and range is essential for effective pest management.