Minnesota Dragonfly

Riverine Clubtail

Stylurus amnicola

The Riverine Clubtail is a mid-sized Clubtail with green eyes and a broadly clubbed abdomen. It is recognizable by the unique pattern on the top of the thorax. They are usually found around medium to large rivers with a swift current

Identification

Field Marks
  • Average adult size is approximately from 1.8 to 2.1 inches
  • Yellow face with thin crossline and other irregular facial markings, dark green eyes
  • The top of the thorax has 2 yellow 'T's', with pointed bottoms, that come together to form an 'I' with a dash on either side
  • Side of thorax is yellow with a bold pair of connected shoulder stripes and a faint, narrow pair of mid stripes that are broken or incomplete
  • Legs black with the base of the hind legs pale
  • Black abdomen with lance-shaped top spots on segments 2 to 7, a triangular top spot on 8, and nothing on top of segments 9 and 10
  • Large yellow patches on the sides of segments 8 and 9 that are as wide as the segments but are bordered by a black lip

Click on photos above for a close-up view.

Field Marks
  • Female is colored similarly to the male
  • Female has fainter facial markings than the male and a cleft in their occiput
  • Abdomen has less clubbing than male with yellow side stripes on segments 2 to 9
  • Small subgenital plates shaped like two right triangles coming together

Click on photos above for a close-up view.

Natural History

Behavior

Although not as wary as many other species of Stylurus, adult Riverine Clubtails are rarely seen. They spend most of their time in the tree tops foraging from perches in the branches. When at the breeding site males typically patrol over the open water. This is the smallest of the Stylurus species in the area but it has the largest club

Habitat

Medium to large rivers with swift current and a silty or muddy substrate

Reproduction

Adults typically hang out in tree tops until mating time. Females lay eggs by dipping their abdomen into the water

Range Maps

Click on the icons above for this species' range maps

Click here for county and state checklists from Odonata Central.

Range maps and checklists courtesy of Odonata Central. Copyright © 2016 OdonataCentral. All Rights Reserved. Abbott, J.C. 2006-2018. OdonataCentral: An online resource for the distribution and identification of Odonata. Available at www.odonatacentral.org.