Monday, May 25, 2020

Flea Beetles

Flea beetle - Kuschelina gibbitarsa  - 1/5 inch (5mm)
As Barb was talking native plants with a visitor to our backyard, I was patrolling with my camera and saw a little black spot on a pipevine leaf.  Moving in on it I got the picture just before it jumped a foot away into the leaves.  The picture above shows four black spots on the pronotum, the middle two clumped and beautiful metalic green elytra, identifying it as Kuschelina gibbitarsa.

 K. gibbitarsa larva - Nature in the Ozarks CC
This is a leaf beetle in desperate need of a common name as K. gibbitarsa is never going to make it popular on the web.  Jumping is not a typical beetle trait but helps define this as a flea beetle.  They have an enlarged hind leg femora (colored red above) that allows it to spring away like a flea when it is disturbed.  Otherwise it will walk over the leaf like other beetles and is able to fly.

The leaf beetle family (Chrysomelidae) is huge with 37,000 species identified.  You would not want to host a family reunion in your backyard as they are strictly herbivorous both as adults and larvae and have diverse appetites.  They tend to eat small holes in leaves which may coalesce into larger holes.  Some species of larva may also eat the roots.

Pigweed flea beetle, Disonycha glabrata
From our unique human perspective developed over the last 9,000 years of agriculture, they can be a problem.  Some species are unpopular pests when they specialize on a crop plant.  Other species are encouraged when they attack plants we consider bothersome weeds.  Although they have food preferences like us, many can adapt to other plants as needed.

Shining blue star
These and other colorful flea beetles like this pigweed flea beetle on Barb's shining blue star (Amsonia illustris) keep our food web "hopping" - feeding other insects and are welcome additions to our backyard full of native plants.  They support the many species of birds that nest nearby, feeding their families.

Plant native species and bring the food web into your backyard.