Sunday, August 21, 2011

Spotted Spreadwing...damselfly of wooded wetlands in Bitterroot Valley

Lestes congener is a brown damselfly belonging to the spreadwing family of Lestidae. There are five species of spreadwings in Montana. Similar in size (~1.5" in length) and habitat selection with bluets and dancers (other damselfy families); they can be differentiated by their habit of spreading their wings at perch. Spotted spreadwing is one of the easier damselflies to identify because it has two spots on the lower part of the thorax (that's looking perpendicular from the side of the animal). Another diagnostic feature is the size and shape of the male cerci and paraprocts (structures to hold the female during reproduction) at the end of the abdomen (see photo below).
Consider having both a close focusing pair of binoculars and a camera (a point and shoot will do) with you when dragonfly watching; photos of damselflies are especially important to assist with identification. Florence Bridge Fishing Access Site is a particularly good spot to observe this species.