Grapevine Beetle: All You Need to Know in a Nutshell

Grapevine Beetles are fascinating insects that draw attention due to their unique appearance and habits. These nocturnal creatures are oval and chunky, with sturdy front legs designed for digging and plates at the ends of their antennae. Their color ranges from pale yellow to a rich saffron, and they can be found in various habitats, such as woodlands, thickets, and vineyards, mainly east of the Great Plains source.

A notable characteristic of this beetle species includes markings on their body, consisting of a spot on each side of the thorax and three on the side of each elytron. Due to their widespread presence and captivating looks, Grapevine Beetles are of interest to both entomologists and casual observers alike. Knowing more about these fascinating creatures helps us appreciate their role in nature and our environment.

Grapevine Beetle: Basic Facts

Overview of Grapevine Beetle

Grapevine Beetles (Pelidnota punctata) belong to the Scarabaeidae family and are found mostly east of the Great Plains, in woodlands, thickets, and vineyards. They are nocturnal insects with sturdy front legs for digging and plates at the ends of their antennae1. The color of these beetles can vary from pale broom-straw yellow to rich saffron, with distinct spots on their thorax and elytra2.

Some characteristics of Grapevine Beetle:

  • Nocturnal
  • Oval-shaped
  • Colors: Pale yellow to saffron
  • Found east of the Great Plains

Scientific Classification

The scientific classification of the Grapevine Beetle is as follows3:

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Coleoptera
  • Family: Scarabaeidae
  • Genus: Pelidnota
  • Species: Pelidnota punctata

Comparison Table of Grapevine Beetle to Other Scarab Beetles

Feature Grapevine Beetle Green June Beetle Japanese Beetle
Color Yellow to saffron Metallic green Metallic green
Size Chunky, oval Nearly 1 inch 7/16-inch
Antennae Plates at ends N/A Clubbed, fan-like
Front legs Sturdy, toothed N/A N/A
Distinct spots Yes4 Bronze to yellow Whitish hairs

Appearance and Identification

Adult Features

The Grapevine Beetle (GB) is a 1-inch, oval-shaped, nocturnal insect, featuring a vibrant off-yellow to tan color. It has six distinct black spots – one on each side of the thorax, and three on each elytron (wing cover). Some key characteristics include:

  • Sturdy front legs designed for digging
  • Plates at the ends of their antennae called lamellae
  • Found in woodlands, vineyards, and other habitats

Adults are often seen on flowers, showcasing their striking color and black spots. Their antennae are highly specialized, with unique endings called lamellae, which can be fanned out for sensory purposes. Their eyes are segmented and adapted to their nocturnal lifestyle.

Larva Features

Larval Grapevine Beetles lack the vibrant coloration of their adult counterparts, featuring a darker shade of brown. They share some similarities with the adults, which are:

  • Cream-colored, elongated bodies
  • Found in the soil near host plants
  • They have well-developed legs and strong mandibles

Examples of these habitats are woodlands, vineyards, and gardens. As they mature and undergo metamorphosis, their color and features change, eventually becoming the vibrant, spotted adults we know.

Comparison of Adult and Larva Features

Characteristic Adult Grapevine Beetle Larva
Color Off-yellow to tan Darker shade of brown
Size 1 inch Smaller than adult
Spots Six distinct spots None
Antennae With lamellae Absent
Habitat Flowers, woodlands Soil near host plants

Distribution and Habitat

Grapevine Beetle Range

The Grapevine Beetle is commonly found in North America, primarily in the United States and Canada. Their range spans from east of the Great Plains, including eastern Canada and parts of Ontario.

Habitats

These beetles prefer various habitats, such as:

  • Forests
  • Woodlands
  • Thickets
  • Vineyards

In addition, they have been observed in regions like Texas and Mexico.

Host Plants

Grapevine Beetles are known to inhabit a variety of host plants, where they feed and reproduce. Some of their favorite plants include:

  • Grapevines
  • Elm
  • Oak
  • Apple
  • Maple
  • Hickory

They are particularly drawn to oaks.

Comparison table:

North America Eastern Canada Ontario
Grapevine Beetle Distribution
  • Example: The Grapevine Beetle can be found in the forests of Texas, feeding on oak trees.

Life Cycle and Behavior

Grapevine Beetle Life Cycle

The life cycle of the Grapevine Beetle (GB) consists of four stages: egg, larva, pupa, and adult.

  • Egg: A female GB lays her eggs in the soil near grapevines or rotting wood.
  • Larva: Hatching from the eggs, the C-shaped larvae feed on decaying plant material for several months.
  • Pupa: After completing their larval stage, they pupate in their pupal chambers in the soil.
  • Adult: Once metamorphosis is complete, adult GBs emerge from the soil in late spring or early summer.

Grapevine Beetle Behavior

Grapevine Beetles, also known as Spotted June Beetles, display some unique behavioral characteristics:

  • They are nocturnal and most active during the night.
  • Attracted to lights at night, they can often be found near lit areas.
  • During summer months, adult GBs can be spotted feeding on the foliage of grapevines and other plants.
  • In the larval stage, GBs are found in the soil and primarily feed on rotting wood.

Some key differences between the Grapevine Beetle and June Beetles include:

Features Grapevine Beetle June Beetles
Adult Size About 1 inch 0.5 to 1 inch
Color Yellow with black spots Brown or greenish-brown
Active Season Late spring to summer May or June

Overall, understanding the life cycle and behavior of the Grapevine Beetle can help with better management practices in vineyards and other affected areas.

Damage to Plants and Control Measures

Damage Caused by Grapevine Beetles

Grapevine beetles are known to eat the foliage of grapevine leaves in gardens and vineyards. The damage caused by these beetles includes:

  • Feeding on grapevine leaves
  • Reducing the overall health of the plant

It is essential to identify these beetles during their larval stage to prevent extensive damage to plants. The larvae of grapevine beetles can be found in rotten wood or tree stumps.

Preventive and Control Measures

To manage grapevine beetle infestations, there are several preventive and control measures that can be applied. Below are some options to control these pests:

Biological control:

  • Introducing beneficial insects or predators like birds to feed on the beetles
  • Utilizing beneficial nematodes and milky spores in the soil to target the larval stage

Chemical control:

  • Utilizing insecticides or chemical treatments when infestations are severe
  • Insecticidal soap spray can be used to target beetles without harming beneficial insects

Physical control:

  • Removing rotten wood and tree stumps where larvae reside
  • Regularly inspecting plants for signs of infestation and handpicking beetles if necessary

Keep in mind that it is essential to strike a balance between chemical use and respecting the environment to ensure the health and safety of other plants, insects, and wildlife.

Control Measures Pros Cons
Biological control Environmentally friendly May take time for results
Chemical control Fast and effective May harm beneficial insects & plants
Physical control No chemical usage Labor-intensive

By understanding the damage caused by grapevine beetles and applying these control measures when necessary, you can better protect the plants in your garden or vineyard, ensuring their continued growth and health.

Footnotes

  1. Field Station

  2. Field Station

  3. Field Station

  4. Field Station

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Grapevine Beetle

 

unknown beetle
I live in southeastern Ontario and recently found a strange beetle flying in my home. I have never seen one like this before. Could you please help me to identify it?
Thanks,
W. Casey

Hi Casey,
This is a Grapevine Beetle, Pelidnota punctata. As its name implies, the adult eats the leaves and fruits of both wild and cultivated grapes while the larvae eat decaying wood in tree stumps. The adult has a rapid curving flight pattern.

Letter 2 – Grapevine Beetle

 

Hi Bugman
I saw this in my hallway. I live in Southern New York State. What is it? Thanks,
Bob Grant

Hi Bob,
This pretty scarab is a Grapevine Beetle.

Letter 3 – Grapevine Beetle

 

Grapevine beetle????
Its been storming on and off all day today and when I went into my kitchen I looked on the screen and I seen this on the window screen my kids wanted to see what it was so i went out and got a bowl. I seen your pics and think its a Grapevine beetle sorry about the pics quality its taken with a web cam. We have no grapevines around here and it was the only one people say they are usually in pairs and there quite large.
Kareen
Goshen, Indiana

Hi Kareen,
You are correct. This is a Grapevine Beetle, Pelidnota punctata. We have gotten several letters recently, without photos, inquiring about white June Bugs. We suspect either Grapevine Beetles or Goldsmith Beetles in those cases.

Letter 4 – Grapevine Beetle

 

Please help
Hi,
My name is Rich from Jackson, Mi. I found this guy on my screen door. Now, to me he look a bit like a lady bug, not enough spots though and waaaay too big. He’s huge. Can you tell me what it is? I’ve never seen one of these b4 and have lived in Michigan 37 yrs. Thank Again
Rich

Hi Rich,
This distinctive Scarab Beetle is known as the Grapevine Beetle.

Letter 5 – Grapevine Beetle

 

2 pictures for you
Please can you put a name to this wonderful creature? I photo’d it and set it free,it tried to fly like a ladybug but was too tired.aproxx 3/4 ” in length
Robert

Hi Robert,
This is a Grapevine Beetle, Pelidnota punctata.

Letter 6 – Grapevine Beetle

 

what is this?
Hi there……can you tell me what this is? It was on my front porch wall near the outside light late one night. Thank you
Carol

Hi Carol,
It would be very difficult to mistake a Grapevine Beetle for any other North American species. In coloration, it ranges from cream, through yellow, orange and even red, but the spotting pattern remains constant.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

1 thought on “Grapevine Beetle: All You Need to Know in a Nutshell”

  1. I just found one of these and posted some pics and a video on my website.

    I think I’m sticking to my theory that it is a government experiment gone wrong though!

    Reply

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