Wisconsin Odonata Survey

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Cordulegaster diastatops  (Selys, 1854)
Delta-spotted Spiketail


Cordulegastridae, Spiketail Family
"Most Wanted" Species

Status-Global/State:

Global: G5     Wisconsin: S1    

Distinguishing Characteristics:

This large, black-bodied dragonfly varies from 2.3 to 2.6 inches in length. Along the black abdomen, there are pairs of long pointed triangular yellow spots. The thorax usually have 3 lateral yellow stripes with the posterior widest stripe and middle narrowest stripe. The forehead is yellow with sea-green eyes. The male's abdomen is slightly clubbed while the female ovipositor (appendages at end of the abdomen) extends length of a segment beyond abdomen. The female is similar with one exception, the yellow on sides of the abdomen forms almost a continuous stripe.

Description of Habitat/Range:

Ranging throughout northeastern United States and southeastern Canada, the delta-spotted spiketail can be found at sunny seepages and small streams, usually spring runs, including boggy ones. In Wisconsin, it is at the western limit of its range.

Flight Season:

The flight season in Wisconsin is not well known, as only a few adults have been documented at one site, in Marinette County, in late June and early July. Throughout its range, the flight season is from mid-May to late August.


Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
88%
(7)
13%
(1)
Shading illustrates monthly percentages of the total flight season records for the species. Each flight season record is a unique date/location/observer combination where one or more adult or an exuvia was recorded (excludes nymphs). The actual number of flight season records for each month is shown in parentheses.

Flight seasons begin earlier in the southern part of the state, often by a week or more. Also, flight charts may not be accurate for rare species because of few data available.
View user-submitted photos

(Click on photos to enlarge)
Photo of Male delta-spotted spiketail
Male delta-spotted spiketail. © Dan Jackson

Male delta-spotted spiketail
Photo of Male delta-spotted spiketail
Male delta-spotted spiketail. © Dan Jackson

Male delta-spotted spiketail
Photo of Male delta-spotted spiketail
Male delta-spotted spiketail. © Dan Jackson

Male delta-spotted spiketail



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