Russet-tipped Clubtail
Stylurus plagiatus
Selys, 1854
Order Odonata
Suborder Anisoptera
Superfamily Gomphioidea
Family Gomphidae
Genus Stylurus
Species plagiatus (Selys, 1854) [Gomphus]
Identification
This is the most widespread of the three hanging clubtails in the region. It is darker than Laura's Clubtail (S. laurae
) and has widely separated humeral and antehumeral stripes. The posterior half of the vertex is green, not black. The eyes are brilliant blue in mature adults. The brown middorsal stripe widens anteriorly, becoming confluent at both ends with the antehumeral stripe. The dark humeral and antehumeral stripes are widely separated by an olivaceous green stripe as stated above. The midlateral stripe is thin, half the width of the humeral stripe and sinuate or interrupted at its upper end. The third lateral stripe is less developed and often interrupted in its lower half. The wings are clear, but may become amber in older females. The legs are as in Laura's Clubtail, pale basally becoming black on the tibiae and tarsi. The pale middorsal abdominal stripe is nearly obsolete on the tawny brown abdomen. Segments 7-10 are expanded laterally and orange-brown as are the caudal appendages.
Size
Total length: 53-66 mm; abdomen: 38-50 mm; hindwing: 20-41 mm.
Similar Species
Two-striped (Aphylla williamsoni
) and Narrow-striped (A. angustifolia
) Forceptails are slightly larger and the sides of their thorax is more brown than green. This is our only hanging clubtail that lacks dark markings on the terminal abdominal segments.
Habitat
Weedy rivers, streams and lakes with moderate to little current.
Discussion
Pairs will often fly into the trees or bushes surrounding streams to mate. Females lay eggs in a fast, low, irregular flight, touching the water at intervals of several meters, or they may rest, perching between these flights. Interestingly, a female of this species has been captured in copula with Black-shouldered Spinyleg (Dromogomphus spinosus
) and a male in copula with a female Southeastern Spinyleg (D. armatus). There is an apparent geographical variation in the eye color of this species, with most individuals, in the region, changing from gray or green to blue with age, but in Florida they remain primarily green (Dunkle pers. comm.).
Distribution
Eastern and southwestern U.S. to Nuevo Leon, Mexico.





