Pacific Spiketail
Cordulegaster dorsalis
Hagen in Selys, 1858
Order Odonata
Suborder Anisoptera
Superfamily Cordulegastroidea
Family Cordulegastridae
Genus Cordulegaster
Species dorsalis Hagen in Selys, 1858 [Cordulegaster]
Syn Cordulegaster deserticola Cruden, 1969
Identification
This is the second of our two western spiketails occurring in the region. It is our only western species with elongated yellow spots medially on each abdominal segment. The eyes are brownish initially but become brilliant blue in mature individuals. The thorax is brown with a pair of broad yellow stripes laterally. The ovipositor extends beyon the abdomen by at least the length of segme
nt 10.
Size
Total length: 71-85 mm; abdomen: 55-64 mm; hindwing: 43-48 mm.
Similar Species
Apache Spiketail (C. diadema
) has bands rather than spots on the abdomen. Bronzed River Cruisers (Macromia annulata
) has a single yellow lateral thoracic stripe.
Habitat
Shady mountain foothill streams and possibly open desert springs.
Discussion
This species is a strong flier patrolling a 1-2 meters off the ground in strong steady bursts allowing at times, for only quick glimpses. It is amazingly adept at darting in, out and around bushes and thick riparian vegetation. Within our region, this species is only known from Rio Arriba, Sandoval and Taos Counties in New Mexico. A paler form of this species is known from the Great Basin and may be a distinct species.
Distribution
Western U.S.





