Food webs in the garden: ladybug beetles

Name that state insect?

The goldenglow aphids in our garden are under attack!  One of the predators that are most easily spotted are these seven-spot ladybird beetles Cocinella septempunctata.  These familiar insects are attracted not by the aphids themselves, but by chemicals that the plants release only when aphids have been feeding on them.  Both the adult and larval beetles are very efficient aphid predators, plucking them off the plant and chewing up their soft bodies with strong jaws.

Probably Coccinella septempunctata eggs

 Adult beetles lay clusters of eggs on leaves that look like clumps of yellow rice.  If you've ever been bitten by a ladybug larva, you know their jaws can deliver a strong pinch!

nom nom nom

 Cocinella septempunctata is not native to the Americas, but was introduced from Europe and by 1973 was established as part of a biological control program for pest aphid species.  This familiar insect was selected as the state insect of 6 states, including Delaware (I probably would have selected an insect more indicative of the region).  Another introduced coccinellid that I commonly find in our garden is the striking twice-stabbed ladybird beetle Chilocorus kuwanae.  There are native Chilocerus that look very similar but I have not yet seen one here.

Next up: fearsome flower flies!