Crossidius coralinus fulgidus

Crossidius coralinus fulgidus | Uintah Co., Utah

Tiger beetles may have been the primary focus of last week’s 9-day, 10-state, 4,700-mile collecting trip; however, they were not the only beetles I was hoping to see. Longhorned beetles (family Cerambycidae) of the genus Crossidius are unusual in the family because of their fall rather than spring/summer adult activity period, and they just happen to occur in dizzying variety throughout the Great Basin and surrounding mountainous areas. Larvae of all species are presumed to feed on the roots of perennial, shrubby, fall-blooming composites, primarily in the genera Chrysothamnus, Ericameria, Gutierezzia, and Haplopappus (Linsley and Chemsak 1961), with the adult activity period undoubtedly timed to allow congregation and mating on the late-season blooms of their host plants.  Only 13 species are currently recognized, but these are further divided into 37 subspecies and innumerable locally distinct populations.  Not having spent much time in the mountain west during the fall, this group has till now been poorly represented in my collection.

The species shown here, Crossidius coralinus fulgidus, was among the first of many that we encountered during our trip.¹  This population was seen near Vernal in northeastern Utah.  It was late in the day and the adults had settled for the night onto the flowers of their host plant, Ericamera nauseosa.  Flower-visiting longhorned beetles are notoriously frustrating subjects to photograph, as their constant movement and long legs and antennae make focus and composition difficult.  These beetles had essentially ceased activity, allowing me to carefully compose and focus the shot, and the low sun in the western sky provided a bright blue eastern sky to use as a colorfully contrasting background.  The photo above (the very long antennae identify it as a male) was taken hand-held with my Canon 100mm macro lens at ISO 400 and 1/60 sec to allow exposure of the sky and flash at an aperture of f/16 to illuminate the subject and achieve good depth of field.  My only criticism of this photo is the small amount of blur seen in the distal antennal segments.

¹ “We” refers to myself and Jeff Huether from Geneva, NY. Jeff is primarily interested in Meloidae but like me also has an interest in Cerambycidae. I was fortunate to have Jeff with me on this trip, as he has collected extensively throughout the Great Basin region and encountered nearly all of North America’s named species and subspecies of Crossidius. It is only because of his prior experience with this group that I was able to find this and several others that we saw during the trip.

ISO 100, 1/200 sec

ISO 400, 1/200 sec

ISO 400, 1/60 sec

Because the beetles were so calm, I spent some time with this female individual trying different settings to see their effect on background color, subject illumination, and detail.  All were taken hand-held using the same lens at f/16, with the left photo also using my “typical” settings of ISO 100 and 1/200 sec.  The background is very dark (in post-processing I might choose to make it black)—good for some subjects but not this one, and although the focus is good the lighting is rather harsh (I had to decrease highlights in post-processing much more than I normally like).  The center photo was taken with ISO increased to 400 and results in a much more pleasing, if still not very natural-looking sky background.  Focus remains good and the shorter flash duration needed reduces the amount of highlighting that needs post-processing adjustment.  Overall I like this photo the best except that the sky is not true in color.  The right photo is also at ISO 400 but uses a slower shutter speed (1/60 sec).  The sky in this photo is the most natural-looking, and as might be expected problems with flash highlights are minimal—it almost looks like a natural light photograph.  However, some amount of motion blur can be detected, especially in the antennae.  Perhaps intermediate shutter speeds (e.g. 1/120 sec) or slightly higher ISO might effectively deal with this while still allowing the truest colors.  What do you think?

REFERENCE:

Linsley, E. G. and J. A. Chemsak.  1961.  A distributional and taxonomic study of the genus Crossidius (Coleoptera, Cerambycidae).  Miscellaneous Publications of the Entomological Society of America 3(2):26–64, 3 color plates.

Copyright © Ted C. MacRae 2011

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About Ted C. MacRae

Ted C. MacRae is a research entomologist by vocation and beetle taxonomist by avocation. Areas of expertise in the latter include worldwide jewel beetles (Buprestidae) and North American longhorned beetles (Cerambycidae). More recent work has focused on North American tiger beetles (Cicindelidae) and their distribution, ecology, and conservation.
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22 Responses to Crossidius coralinus fulgidus

  1. I’m not going to try to comment on the shutter speed question as I think you are more advanced as a photographer than I am, but I do love that you’re continuing to work on the things you learned at BugShot. Really love the bright blue sky behind the beetle, even with the motion blur! The colors are so beautiful.

  2. Nice shots Ted! It is like seeing an old friend! I grew up with two species of Crossidius that occur along the southern fringes of the Mojave Desert in California.

  3. I like the second image of the beetle best, but that sky color is kind of creepy, unless you think of it as a sheet of blue-gray cardboard. Any way to transfer the background of picture #3 to picture #2?

    Gorgeous bug, b. t. w.!

  4. Henry (Rob) Robison says:

    Wonderful photos of a truly great-looking beetle! Nice job Ted! BugShot 2011 was really a learning experience, wasn’t it?

  5. Jon Q says:

    With a trip like that, i’m sure you encountered all kinds of Beetles! Hopefuly, next may i’ll be taking a trip to the gulf coast of mexico, so with your blog in mind, i’l be keeping an eye out for tigers!

    • It was about as good a trip for beetles as a fall trip can be.

      I’ve not visited the Gulf Coast of Mexico so can’t offer any specific advice on tiger beetles. In general, beaches and open ground (sandy, clay, alkaline) are good places to look.

  6. TGIQ says:

    Wow, you’re certainly putting BugShot to good use here! I love the contrast between the blue sky and the yellow flower. Beautiful beetle, too!

  7. hemachatus says:

    I quite like the ISO 100 shot as the black background picks up the black on the beetle.

    • Perhaps I’ve just gotten a little bored with black backgrounds since that is how many of my shots turn out. Still, I think the blue background is the hands down winner for value contrast (motion blur notwithstanding).

  8. Alex Wild says:

    Yeah, the motion blur is a bit of a problem on the blue-background shot. I wonder if a tripod, tripod, tripod might come in handy, and/or ISO 800 for 1/120 sec.

    • I tripod would help, but it wouldn’t solve the problem entirely as it’s a combination of both camera movement and wind.

      Besides, if I lug a tripod around how will I carry my net, net, net? :)

  9. Personally for the insect the second image is the best and I think you could tweak the sky in post to make it look more natural. While the sky is the nicest in the third image I think the yellow is a bit over exposed and you have the motion blur as well. All three images are well done though and thanks for sharing them.

  10. Ted I’m far from a phtotoshop guru there are a bunch of alternatives with this image. Since it looks like the sky color is pretty much isolated to the sky it may be as simple as a hue/saturation adjustment layer possibly coupled with a channel mixer adjustment layer. If that doesn’t do it the next step would be to use a color adjustment brush to paint over the sky color with a more realistic sky color. Another possible direction is to use the image->adjustment->replace color function. All of these are fairly easy to use and just require playing around. As always do these on a separate layer to preserve the original image. Also if you do this on a separate layer you can always play with masking and painting over the mask to restore/fix things if you go to far.

  11. Pingback: Cicindela albissima—The Coral Pink Sand Dunes Tiger Beetle « Beetles In The Bush

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