pronghorn clubtail

(Phanogomphus graslinellus)

Conservation Status
pronghorn clubtail
  IUCN Red List

LC - Least Concern

     
  NatureServe

N5 - Secure

SNR - Unranked

     
  Minnesota

not listed

     
           
           
 
Description
 
 

Pronghorn clubtail is a relatively robust, medium-sized dragonfly. It occurs mostly in central United States and southern Canada. In Minnesota it is most common in the central and north-central regions, less common in the metro and southeast regions, rare in the Arrowhead, and absent from the southwest.

Adults are 1¾ to 2316 (44 to 55 mm) long. The body is black with extensive yellow markings.

The head is small. The face is greenish-yellow. The large compound eyes are blue or gray and do not meet at the top of the head. The area behind the compound eyes at the top of the head (occiput) on both sexes is yellow.

The thorax is yellowish-green or greenish-yellow with several black stripes. The middle stripe on the upper side (middorsal stripe) is broad and has parallel sides. On each side there are two upper stripes (humeral and antehumeral stripes) that are partly fused together but separated in the middle by a thin pale stripe.

The abdomen is slender and black with yellow markings. The upper (dorsal) surface or abdominal segments 1 through 7 have yellow, elongated, triangular spots. Segment 8 has a triangular spot at the base and sometimes a thin line extending from the triangle to the rear margin of the segment. Segment 9 has a broad stripe from the base top the rear margin. Segment 10 has a narrower stripe. Segments 8, 9, and 10 are expanded into a noticeable “club”. The sides of segments 8 and 9 have bright yellow along the entire margin. At the tip of segment 10 the male has a pair of distinctive, widely forked claspers (cerci). Each cercus has an outward-pointing “horn”, like a pronghorn antelope, for which this dragonfly gets its common name.

The legs are dark brown to black. The third leg segment (femur) on the female is streaked with green, on the male black it is entirely black. The upper (dorsal) surface of the fourth leg segment (tibia) on both sexes is yellow.

The wings are clear except for a dark cell (stigma) on the leading edge near the tip. The leading edge of the vein on the front margin (costa) of each wing is bright yellow.

 
     
 

Size

 
 

Total Length: 1¾ to 2316 (44 to 55 mm)

 
     
 

Similar Species

 
     
     
 
Habitat
 
 

Ponds, lakes, and slow streams.

 
     
 
Biology
 
 

Season

 
 

Mid-May to mid-August

 
     
 

Behavior

 
 

 

 
     
 

Life Cycle

 
 

 

 
     
 

Nymph Food

 
 

 

 
     
 

Adult Food

 
 

 

 
     
 
Distribution
 
 

Distribution Map

 

Sources

7, 17, 27, 29, 30

IUCN Red List

 
  7/17/2020      
         
 

Occurrence

 
 

Common

 
         
 
Taxonomy
 
 

Order

Odonata (dragonflies and damselflies)  
 

Suborder

Epiprocta  
  Infraorder Anisoptera (dragonflies)  
 

Superfamily

Aeshnoidea  
 

Family

Gomphidae (clubtails)  
 

Genus

Phanogomphus  
       
 

Until recently, this dragonfly was classified as Gomphus graslinellus. In 2007, the four subgenera were raised to genus rank. The genus Gomphus now contains only European species.

 
       
 

Synonyms

 
 

Gomphus graslinellus

 
       
 

Common Names

 
 

pronghorn clubtail

 
       

 

 

 

 

 

Glossary

Cercus

One of a pair of small sensory appendages at the end of the abdomen of many insects and other arthropods. In Odonata, one of the upper pair of claspers. Plural: cerci.

 

Costa

On ferns: The central axis of a pinna, to which pinnules are attached. On mosses: the central axis (midvein) of a leaf. On insects: The vein on the leading edge of the forewing.

 

Femur

On insects and arachnids, the third, largest, most robust segment of the leg, coming immediately before the tibia. On humans, the thigh bone

 

Occiput

The back of the head. In Odonata, Megaloptera, and Neuroptera, the upper part of the head behind the eyes.

 

Stigma

In plants, the portion of the female part of the flower that is receptive to pollen. In Lepidoptera, an area of specialized scent scales on the forewing of some skippers, hairstreaks, and moths. In other insects, a thickened, dark, or opaque cell on the leading edge of the wing.

 

Tibia

The fourth segment of an insect leg, after the femur and before the tarsus (foot). The fifth segment of a spider leg or palp.

 

 

 

 

 

 
 
Visitor Photos
 
           
 

Share your photo of this insect.

 
  This button not working for you?
Simply email us at info@MinnesotaSeasons.com.
Attach one or more photos and, if you like, a caption.
 
 

 

 
 

 

 
           
           
 
MinnesotaSeasons.com Photos
 
    pronghorn clubtail   pronghorn clubtail  
           

 

Camera

     
 
Slideshows
 
 
     
     
     

 

slideshow

       
 
Visitor Videos
 
       
 

Share your video of this insect.

 
  This button not working for you?
Simply email us at info@MinnesotaSeasons.com.
Attach a video, a YouTube link, or a cloud storage link.
 
 

 

 
     
     
       
       
       
 
Other Videos
 
  Clubtail Dragonfly (Gomphidae: Gomphus) Waiting for Prey
Carl Barrentine
 
   
 
About

Jun 13, 2012

Photographed at the Turtle River State Park, North Dakota (12 June 2012). Either a female Gomphus graslinellus or a Gomphus exilis, I think.

 
  Pronghorn Clubtail
Bob Rubey
 
   
 
About

Jun 20, 2015

Silver Springs SP, Yorkville, IL
June 19, 2015

 
       

 

Camcorder

 
 
Visitor Sightings
 
           
 

Report a sighting of this insect.

 
  This button not working for you?
Simply email us at info@MinnesotaSeasons.com.
Be sure to include a location.
 
   

 

   
           
 
MinnesotaSeasons.com Sightings
 
   

 

 

Binoculars


Created: 7/17/2020

Last Updated:

About Us | Privacy Policy | Contact Us | © 2021 MinnesotaSeasons.com. All rights reserved.