The 35 spp. of North American Bluets (Enallagma spp.) are small, about 30mm long, damselflies that are notoriously difficult to ID in the field; females more so than males.
Fortunately the male terminal appendages, viewed in profile, are diagnostic for most species. This means netting the specimen and examining it with a 10x-20x hand lens.
Some books provide decent drawings of the terminal appendages but the best reference tools are photos. Photomacrography stacks are ideally suited for getting such photos.
Top photo: male (blue) and female of unknown sp. (Kd 64 slide) (several possibilities).
Bottom: male terminal appendages of a male Marsh Bluet (Enallagma ebrium) showing the distinctly forked cerci (actually the right cercus of a pair of cerci).
reversed 50/2.8 El-Nikkor @ f/5.6, 26cm extension; 15 frames @ 0.04mm HF stack. Cropped top and bottom but full width frame of 4.2mm on a 23.7mm sensor.
Damselflies
Moderators: rjlittlefield, ChrisR, Chris S., Pau
Damselflies
NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.
Nikon camera, lenses and objectives
Olympus microscope and objectives
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.
Nikon camera, lenses and objectives
Olympus microscope and objectives