Showing posts with label Calico Pennant. Show all posts
Showing posts with label Calico Pennant. Show all posts

Wednesday, June 11, 2014

The Dragonflies of Drag Lake

Drag Lake is located about 7.25 km west of Tweed , at 44.443129°, -77.391084° along the trans-Canada Trail according to Google Maps. The lake appears to be rock-bottomed – calcerous, judging by the surrounding geology – with relatively shallow water, and the parts of the shoreline are bordered by marshes. Some odonates can be particular with regard to their habitat requirements and for whatever reason the Dusky Clubtail is plentiful at this body of water.

With a length of 50 mm ± 5 mm, Gomphus spicatus is larger than the Lancet Clubtail (44 mm ± 5 mm). As its name suggests the Dusky Clubtail tends to be darker than its cousin, lacking the Lancet Clubtail's yellow dorsal stripe on S9.


However, the dragonflies can vary in color and Gomphids are notorious for their mutable chromatic complexions in any event, with yellow becoming green and eventually changing to bluish-gray with increasing age. Both the Dusky and Lancet Clubtails can sport a pale yellow streak on S9 making this unreliable means of separating the two species. For a positive ID it's necessary to examine the claspers and/or genitalia.


Like most Gomphidae a.k.a. Clubtails, Dusky Clubtails perch on the ground or other horizontal surfaces such as low leaves. They are fairly tame (the individuals in these photos were captured by hand) and can often be approached closely, whereupon the lateral spines on the male's cerci are clearly visible.


The cerci also have a distinct ventral spine.


The male's secondary genitalia, looking at this picture the words such as baroque, labyrinthine and convoluted come to mind ...


The abdomens of the females tend to be more robust than those of males. The distribution of the sexes was rather odd, with thirty one males but only two females being encountered.



A macro of the female's genital plate.



There were plenty of exuviae scattered along the shoreline but none belonging to the Dusky Clubtail were in evidence. Although unconfirmed as yet (the images are at BugGuide.Net) the largest exoskeletons probably belonged to Epitheca princeps, the Prince Baskettail – but no Prince Baskettails were seen flying.







EDIT ... the response from BugGuide.Net: if there are four setae on the edges of the palps (which there are) the exuviae belong to Epitheca princeps. Also, according to this key at Odonata Larvae of Michigan the dorsal surface of prementum should be setose, which is the case in the specimens. So Epitheca princeps it is.




Four teneral female Calico Pennants (Celithemis elisa) were also sighted perching in the tall grasses, and apparently this dragonfly also finds the atmosphere of Drag Lake convivial. The Calico Pennant is not uncommon at other wetland habitats in south-central Hastings County, but in the coming summer months uncountable numbers of these colorful little skimmers can be found flying at Drag Lake.



The Belted Whiteface (Leucorrhinia proxima) and the Frosted Whiteface (Leucorrhinia frigida) are another pair of dragonflies that can be tough to distinguish at a glance. They are very similar in size, coloration and patterning, and both species develop pruinosity on the first few abdominal segments.

This Belted Whiteface was captured near a marsh a couple of kilometers east of Drag Lake, and examination of the hamules (top) and claspers (bottom) is the best means of distinguishing it from the Frosted Whiteface.

Saturday, July 17, 2010

Calico Pennant (Celithemis elisa)

At 30 mm in length this dragonfly is smaller than the Halloween Pennant. The Calico Pennant seems to be less common in this area than the Halloween Pennant. In the past I've found Calico Pennant remains on a couple of occasions but this is my first encounter with a live one. Note the distinctly red face ...

... and the large patch at the base of the hindwing. The remaining markings on the wings are spots (compare these to the bands on the wings of the Halloween Pennant).

The bold red triangles on the abdomen and red sides of the thorax indicate this is a male.

Almost one year later ... I stumbled across the Calico Pennant's breeding site. A small sand-and-stone bottomed creek bordered with dense vegetation runs near the intersection of Alexander Street and the Eastern Ontario Trail. And surprise! three females were foraging in the tall grass and wildflowers. So this dragonfly isn't uncommon after all, it's just a matter of being in the right place at the right time ...

Another local Calico Pennant habitat: several males and a female were encountered at a marsh on the Upper Flinton Road, abouyt 150 m east of Moores Road.