North America
Identification: This species is similar to several common species but is restricted in range. It is smaller than most other darners and flies earlier in the season, from about March until July. Predominately blue and black western species.
Size: Total length: 67-74 mm; abdomen: 45-52 mm; hindwing: 42-47 mm. Small for the neotropical / mosaic darner group. Slightly smaller and less bulky than Blue-eyed Darner; larger than Flame or Neon Skimmer.
Similar Species: The Neotropical (Rhionaeschna) and very similar Mosaic (Aeshna) darners present many identification challenges. This species is difficult to separate in the field from several similar (and often more common) darners.
Compared to Blue-eye, California Darner has paler thoracic stripes; is slimmer and less heavy-bodied; lacks the short blue stripes on front top of the thorax (vs fairly obvious in Blue-eyed); has darker gray-blue eyes (vs brilliant blue); the twin blue dots on the final abdominal segment are closer together, almost touching (vs widely separated in Blue-eyed); California has a single cerci (vs. forked in Blue-eyed). (Adapted from Don Roberson https://creagrus.home.montereybay.com/CaliforniaDarner.html.)
See also: Kathy Biggs's California Odonates, Dennis Paulson Ode Photos Website
Habitat: Open sunlit areas of ponds, lakes, slow streams.
Seasonality: This species is normally found from Feb - July, but is most common earlier in the year.
Distribution: Western North America from British Columbia to Baja California, west to Montana, western South Dakota, Wyoming, Colorado, NE Nebraska, and Arizona.
Credits: David Bell
