GRAPEVINE BEETLE: Pelidnota punctata

Longtime readers probably remember my occasional foray into the realm of entomology (not to be confused with my passion for etymology). It's been a while since I've felt motivated enough to look closely at nature's unexpected critters. After all, we didn't have too many guests before we started gardening at Toronto House.

A lovely grapevine beetle was one of our first visitors this year.  Might as well document him here and add the observation to iNaturalist.


Spotted June Beetle, Spotted Pelidnota  
BINOMIAL NAME: Pelidnota punctata  
IUCN RED LIST:  Not evaluated
ADULT SIZE (Length, not including legs): approximately 2.5 centimeters but can reach 3 cm IDENTIFYING MARKS: off-yellow or auburn red with three black-spot-patterns on each side. The elytra are divided with thin, black lines.

 KINGDOM: Animalia
  PHYLYM: Arthropoda
   CLASS: Insecta
    ORDER: Coleoptera
     SUBORDER: Polyphaga

      SUPERFAMILY: Scarabaeidae
       FAMILY: Scarabaeidae
        SUBFAMILY: Rutelinae

         TRIBE: Rutelini
          GENUS: Pelidnota
            SPECIES: punctata

Grapevine Beetle on our screen door
Large, golden-yellow to orange scarab with peripheral spots on pronotum and elytra. Often mistaken for a ladybug, this scarab is not in the same Family (Scarabaeidae vs Coccinellidae). This northern specimen from Ohio has dark legs.

UNITED STATES: eastern coast of North America, as well as Florida, Nebraska and north western Missouri, central Indiana, South Dakota, Minnesota, southern Wisconsin, and southern Michigan. Also just found in northwestern Kentucky, southwestern Ohio, Illinois, Maryland, New York, southwestern Connecticut, Pennsylvania, northern Michigan, eastern West Virginia, northern Iowa, North Carolina and Texas.
CANADA:  Southern Ontario.

Commonly seen during summer months, adult grapevine beetles prefer to eat the leaves of grapevines but may also prey on the leaves and flowers of deciduous trees, shrubs and other plants. They are not known to inflict serious damage to plants. Adults can be found in woodland, thicket, vineyard and garden habitats.

The adults are active flyers often attracted to lights at night. The flight is characterized by fast speed and curved patterns though most are observed in frantic flight around a light source.

Grapevine beetle larva (from:
The grubs inhabit soil and decaying matter, and primarily feed on rotting wood. However, they will feed on plant roots and can be considered pests in gardens and in grassy lawns if numbers are sufficient. Grubs occasionally attack vegetables such as lettuce, raspberry, strawberry, and young ornamental trees. Affected plants will suddenly wilt or shed leaves prematurely.  These grubs feed below ground for 3-4 years before metamorphosis into adult form.They are not known to be vine borers.

These beetles do not take kindly to camera flash. They tend to furl antennae and hunker down, but will go about their business moments later.