Species severus Hagen, 1874 [Ophiogomphus]
Syn Ophiogomphus montanus Selys, 1878
This is another western species similar to Arizona Snaketail (O. arizonicus). See the description under that species for details. It differs in range and in the following respects. The males have an epiproct longer than the cerci. Females la cking erect spines on the occipital ridge.
Total length: 50-52 mm; abdomen: 35-38 mm; hindwing: 29-34 mm.
This species can be distinguished from Arizona Snaketail by the above characters. Other similar species are given under that species account.
Primarily rivers and streams with a strong current and cobble bottom; occasionally larger lakes with mud substrate.
Males often exhibit the characteristic body posture of this group, perching on exposed rocks with the tip of the abdomen curled downward in a snake-like position. They may forage and patrol from these rocks or from vegetation perches low to the ground. Pale Snaketail is found farther north than Arizona Snaketail.
Western U.S. and Canada.