Poplar’s snout weevil

(Lepyrus palustris)

               
Conservation Status

IUCN Red List

not yet assessed

Poplar’s snout weevil

NatureServe

NNR - Unranked

Minnesota

not listed

Occurrence

Uncommon

Flight/Season

Year-round. One generation per year.

Habitat

Deciduous forests

Size

Total Length: ½ to

         
          Photo by Bill Reynolds

Identification

This is a medium to large sized weevil. The male is about ½ long. The female is larger, just under long.

The body is black and is sparsely covered with gray and yellowish hair-like scales.

The thorax is short, cone-shaped, and significantly narrowed in front. It is composed of three segments. The first segment (prothorax) is large and prominent and appears to be the entire thorax. It is covered by a saddle-shaped plate (pronotum). The pronotum is 1¼ times longer than wide and 1½ times wider at the base than at the apex (near the head). It is coarsely and densely wrinkled and pitted. The base and apex are straight across, not rounded or wedge-shaped. The sides are only slightly rounded. There is a pale slanted stripe on each side.

There are two pairs of wings, a membranous inner pair and a hardened outer pair (elytra). The elytra are attached to the second thoracic segment (mesothorax). They are 1½ times longer than wide. They cover the mesothorax, the third thoracic segment (metathorax), and completely cover the abdomen. They are oblong egg-shaped, narrowed toward the tips, and moderately convex. They have a small, pale spot in the middle and are covered with rows of longer, denser, white or yellowish scales. The intervals between the rows of scales finely and densely pitted.

The head is greatly elongated between the eyes and the mouth parts forming a conspicuous snout. The snout is slightly longer than the thorax. It is slightly bent downward, almost cylinder-shaped, and enlarged toward the tip. It is densely covered with fine pits that are distinct from the base to the tip. The antennae are short and slender. The last 3 segments are expanded and form a club. There are seven jointed segments between the base and the club. The first two segments are long, the second much longer than the first. The third through seventh segments are short.

The third leg segment (femur) has a pale ring-like band and is armed with a small tooth on the inner side. The fourth leg segment (tibia) is armed on the inner side near the tip.

 
Similar
Species

 


Larval Food

Roots of soft trees, including willow (Salix), sassafras (Sassafras), and poplar (Populus).

 
Adult Food

Leaves of soft trees, including willow (Salix), sassafras (Sassafras), and poplar (Populus).

 
Life Cycle

Adults overwinter. In May or June the female lays 100 to 140 eggs on the ground near a host plant. When the eggs hatch the larvae enter the soil and feed on the roots. They pupate in the soil and emerge in July as adults.

 
Behavior

 


Distribution Distribution Map  

Sources: 24, 27.


Comments

Pest
In Europe and Asia this species is considered a pest because it damages basket willow, a cultivated plant.


Taxonomy

Order:

Coleoptera (beetles)

 

Suborder:

Polyphaga (water, rove, scarab, long-horned, leaf and snout beetles)

 

Infraorder:

Cucujiformia

 

Superfamily:

Curculionoidea (snout and bark beetles)

 

Family:

Curculionidae (snout beetles, weevils)

 

Subfamily:

Molytinae

 

No Rank:

unclassified Molytinae

 
Synonyms

Curculio colon

Lepyrus geminatus

Lepyrus pinguis

 
Common
Names

Poplar’s snout weevil


 

 

 

 

 

 

 

Glossary

elytra

The hardened forewings on an insect used to protect the fragile hindwings, which are used for flying, in beetles and true bugs.

 

femur

In insects, the third, largest, most robust segment of the leg, coming immediately before the tibia. In humans, the thigh bone.

 

pronotum

The saddle-shaped, exoskeletal plate on the upper side of the first segment of the thorax of an insect.

 

prothorax

The first (forward) segment of the thorax on an insect, bearing the first pair of legs but not wings.

 

tibia

The fourth segment of an insect leg, after the femur and before the tarsus (foot).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

       

Visitor Photos

   
Share your photo of this insect.

Bill Reynolds


This weevil is a parasite of softwood forest. In the area I found the weevil, Poplar trees are everywhere.

  Poplar’s snout weevil    

       
       
       

MinnesotaSeasons.com Photos

   

 

       
       

 

Camera

     

Slideshows

   
     
     
     

 

slideshow

     

Visitor Videos

   
Share your video of this insect.

     
     

Other Videos

 
     
     

 

Camcorder

         

Visitor Sightings

   
Share your sighting of this insect.

Bill Reynolds
8/4/2003

Location: St. Louis Co.

This weevil is a parasite of softwood forest. In the area I found the weevil, Poplar trees are everywhere.

Poplar’s snout weevil


     
     
 

MinnesotaSeasons.com Sightings

   

 


 

 

Binoculars

Last Updated:

About Us | Privacy Policy | Contact Us | © 2017 MinnesotaSeasons.com. All rights reserved.