Wednesday, May 07, 2008

Ebony Jewelwing

The Ebony Jewelwing (Calopteryx maculata) is a damselfly and not a dragonfly.  The name comes from the Greek "kalos" or beautiful and "pteron" or wing along with the Latin "macula" or spot, which refers to the spot on the female's wing.  Remember, the female's accessorize.  The female's body is also more gray to black while the male's is a metallic blue or green.

Visitors to the Audubon Center at Francis Beidler Forest will see plenty of Ebony Jewelwings.  As damselflies, they move their wings like a butterfly and fold their wings in the vertical position when they are at rest.  Dragonflies move their wings rapidly in a near-horizontal plane and keep their wings in the horizontal position when at rest.  Both dragonflies and damselflies are of the order Odonata.  

Like dragonflies, damselfly mating is complicated.  The male transfer the sperm from the terminal end of his abdomen to the hamules (a secondary sex organ) about midway up his abdomen.  The male then clasps the back of the female's head with the end of his abdomen, which in some species of damselflies and dragonflies can injure the female.  The female then bends her abdomen to receive the sperm from the male's hamules.  This give the "wheel" or "heart" appearance when the male and female or paired.  The female will then force her eggs singly into soft plant tissue below the water's surface.  The naiads that hatch will live in shallow water.  Like dragonfly naiads, damselfly naiads prey on small aquatic insects and other arthropods.  Many naiads achieve "jet propulsion" locomotion by shooting water out of their rectal openings.  Feel free to use that in middle school science class!

Image by Mark Musselman

No comments: