Family: Coenagrionidae
Length: typically 34-38 mm
The Dancers are a group of damselflies named for their bouncy, dance-like flight. They are notable for often perching on the ground. They may also be seen perching on rocks, logs, and sidewalks, and may also rest on plants.
The mature male Blue Fronted Dancers thorax resembles a faceted gemstone, with only the thinnest of black lines separating the various regions of the thorax. On the rear of the abdomen, segments eight, nine, and ten are blue.
Females and immature males can be a little tricky to identify, and resemble the females and immature males of other species of Dancers. To complicate matters, as with several other species of Dancers so with the Blue-Fronted there are two female color forms. The blue form female has a blue thorax and looks similar to the male but without a blue tip on the abdomen. The brown form looks similar to other various other female Dancer species. The photos below show what to look for to separate female Blue-Fronted Dancers from females of other species.
Argia apicalis, as well as Argia tibialis, have the highest chromosome number (nineteen) of any Odonate. The genus Argia has neotropical origins, and these two species apparently evolved rather recently in what is today the United States (Pritchard, 1982).
George and Juanda Bick (1965) studied this species at a small pond in a pasture in Oklahoma, in a mark-and-recapture study. They found the males in two color forms, bright blue and a dark grayish-black. Females were in three color forms: brown, turquoise, and gray-black (in all cases the color referred to is the thoracic color). Other researchers had reported seeing all these color forms, but had assumed they were age-related. Bick and Bick, though, reported seeing all color forms mating, thus showing that none of the color forms was an immature coloration.
Studying the color forms more systematically, the Bicks showed that many individuals moved regularly from one color form to another. One particularly talented male changed color eight times in twelve days. Some individuals changed from light to dark to light, while others changed from dark to light to dark. While the authors never settled on a firm explanation for the various color forms, they asserted such color forms were not related to age or mating history, to temperature or humidity, or to the color of their perch.
In a number of mountain counties in West Virginia Blue-Fronted Dancers have not been collected, but otherwise from May to September this species may be seen in most areas of West Virginia.
At first glance it appears there are four eyespots, but the front two are not discrete spots, instead continuing into the coloration of the face. |
This is the brown form female. The top of the abdomen appears mostly black (just a very thin pale line there) and on segment nine there are some noteable dark areas on the top and sides. |
The face of females is much like that of the males, except (on the brown form females) it is brown instead of blue. This female is finishing off a tidbit. |
Insects of West Virginia