To date three spiketail species (Family Cordulegastridae) and two cruiser species (Family Macromiidae) have been observed in the Ottawa-Gatineau area. They are all relatively large brownish or black dragonflies with yellow stripes down the side of the thorax (two stripes on spiketails and one on cruisers) and yellow spots or markings down the top of the abdomen. All are easily identified from photographs that show a top view.
The eyes of the species in the spiketail family appear teardrop-shaped when viewed from above, either meeting at a single point in the center or separated by a small gap. The eyes of the brown cruisers (i.e. the Stream Cruiser in our region) also have eyes that meet at a single point but are more rounded than those of the spiketails, with a bulbous occiput above. The eyes of the river cruisers (i.e. the Swift River Cruiser) have eyes that are even more rounded, appearing lemon-shaped and meeting along a seam.
Spiketails are most often found cruising over small to mid-sized streams, while cruisers prefer lakes or rivers, though all members may be found foraging away from the water. Both spiketails and cruisers are more likely to perch than darners, with spiketails hanging vertically from the vegetation and cruisers perching vertically or at an oblique angle.
Neither family is abundant in Ottawa, and the Stream Cruiser is the only species that is considered to be widespread, inhabiting a variety of streams in Ottawa. This is also the cruiser that is most likely to be found patrolling wooded trails (though darners and emeralds do so as well).
Status and Flight Season in Ottawa-Gatineau
Examples of Species:
Twin-spotted Spiketail (Zoraena maculata)
This species is more easily found in Gatineau Park than in Ottawa; the only place I’ve seen it in Ottawa is in Marlborough Forest where it patrols forest brooks shaded by trees. It is identified by the pairs of half-moons down the length of its abdomen. It will often take a break from its patrols by perching on a branch close to its stream, usually on a dead branch containing no leaves.
Delta-spotted Spiketail (Zoraena diastatops)
Another species that is easier to find in the streams of Gatineau Park, the only place it has been recorded in Ottawa is Larose Forest east of the city. It prefers more open, shallow streams such as those found in beaver meadows rather than forest. The paired spots on the abdomen are triangular in shape.
Arrowhead Spiketail (Zoraena obliqua)
The most difficult spiketail species to find in our region, I’ve actually seen it in more places in Ottawa than Gatineau. It breeds in small, shallow forest streams that are at least partially shaded, though it also hunts in open areas away from the water. In Ottawa I have found them in Larose Forest, the South March Highlands, Stony Swamp, and in Marlborough Forest. This species is easily identified by the single row of spots down the abdomen that are shaped like arrows.
Swift River Cruiser (Macromia illinoiensis)
This dragonfly is black in colour with small yellow spots along the middle of the abdomen followed by one large yellow spot near the tip that makes it identifiable even in flight. It is found along the Ottawa River in places like Mud Lake, Sheila McKee Park and Morris Island, although it can turn up anywhere, flying high above woodland openings or about a foot above the Ottawa River on lengthy patrols.
Stream Cruiser (Macromia transversa)
Formerly placed in the now-defunct genus Didymops (the brown cruisers), this distinctive dragonfly is brown rather than black, with whitish-yellow spots along the top of the abdomen becoming paired toward the end, a flared abdomen, and white claspers. It regularly patrols streams, lake shores, and woodland trails, usually below waist height. They are more likely to perch than Swift River Cruisers in my experience, often low to the ground.
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