Revisited: Dogbane Leaf Beetle (Chrysochus auratus)

16 07 2011

Originally posted July 11, 2010

I stalked this beetle at the McKee-Beshers Wildlife Management Area this morning for at least 20 minutes—it wasn’t hard; he moved up and down the same sunflower leaf the entire time. I was just mesmerized by his rainbow coloring! In researching what type of beetle it was, I came across this site here, which describes this insect’s beautiful coloring:

The dogbane leaf beetle has a special type of color that shines and changes as the insect changes position or we change position looking at it. This changing color is called iridescence. The beetles’ iridescence is produced by special body structures and light. The surface of the body parts of this beetle is made up of stacks of tiny, slanting plates, under which is a pigment (substance that produces color). Some light rays reflect from the surface of the plates, and other light rays reflect from the pigment underneath. At different angles, the light reflects at different speeds, causing interference and resulting in our seeing different colors that shine.

Adult beetles feed on Dogbane (Apocynum cannabinum)—hence its name—and milkweed. I’m glad I didn’t touch the little guy—apparently they avoid some predators by giving off a foul-smelling secretion when they are touched!

© Cindy Dyer. All rights reserved.

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Dogbane Leaf Beetle (Chrysochus auratus)

11 07 2010

I stalked this beetle at the McKee-Beshers Wildlife Management Area this morning for at least 20 minutes—it wasn’t hard; he moved up and down the same sunflower leaf the entire time. I was just mesmerized by his rainbow coloring! In researching what type of beetle it was, I came across this site here, which describes this insect’s beautiful coloring:

The dogbane leaf beetle has a special type of color that shines and changes as the insect changes position or we change position looking at it. This changing color is called iridescence. The beetles’ iridescence is produced by special body structures and light. The surface of the body parts of this beetle is made up of stacks of tiny, slanting plates, under which is a pigment (substance that produces color). Some light rays reflect from the surface of the plates, and other light rays reflect from the pigment underneath. At different angles, the light reflects at different speeds, causing interference and resulting in our seeing different colors that shine.

Adult beetles feed on Dogbane (Apocynum cannabinum)—hence its name—and milkweed. I’m glad I didn’t touch the little guy—apparently they avoid some predators by giving off a foul-smelling secretion when they are touched!

© Cindy Dyer. All rights reserved.