Fujifilm/Fringer/Canon MP-E 65mm macro lens

In a recent blog post I mentioned that I was looking forward to testing the Fringer EF-FX Pro II lens mount adapter with my Canon MP-E 65mm Macro lens.

The MP-E 65mm doesn’t have a ring for focusing on the subject — you set the magnification ratio (from 1x to 5x) and move the camera/lens rig back and forth until the subject is in focus. For all photos, I focused on one eye of the model.

Dimetron

The first studio model is a toy Dimetron, photographed at a magnification ratio of 1:1. The toy is ~3.6 cm (~36 mm) long. The size of the APS-C sensor in the Fujifilm X-T3 is 23.5 mm x 15.6 mm. At 1x magnification, the entire length of the toy doesn’t fit on screen.

Dimetron toy | 1:1 magnification | 1/16 flash power ratio

With the camera/lens set for the same f/stop, shutter speed, and ISO (f/5.6, 1/250 s, and 400, respectively), less light reached the sensor when the magnification ratio was increased from 1:1 to 2:1. So I increased the flash power ratio by one stop, from 1/16 power to 1/8 power.

Dimetron toy | 2:1 magnification | 1/8 flash power ratio

Triceratops

The last studio model is a toy Triceratops, photographed at a magnification ratio of 1:1. The toy is ~4.3 cm (~43 mm) long.

Triceratops toy | 1x magnification | 1/16 flash power ratio

As with the first model, when the magnification ratio was increased from 1:1 to 2:1 it was necessary to increase the flash power ratio by one stop.

Triceratops toy | 2x magnification | 1/8 flash power ratio

Gear Talk

The Fringer EF-FX Pro II lens mount adapter enables one to mount Canon lenses on Fujifilm X-Series digital cameras. As you can see, my Canon MP-E 65mm macro lens works well with the Fujifilm X-T3 camera.

The APS-C sensor inside the Fujifilm X-T3 digital camera has a crop factor of 1.5x, so the Canon MP-E 65mm macro lens has a focal length of ~98mm (35mm equivalent) when mounted on an X-T3. The net result is an increase in apparent magnification, …

Post Update Update

Just because something looks like a duck and seems to act like a duck doesn’t mean it’s a duck. And so it is with the Fringer EF-FX Pro II lens mount adapter — although it looks like an extension tube, it isn’t. Why was I deceived by its appearance? Because I didn’t understand something called “flange focal distance.”

For an interchangeable lens camera, the flange focal distance (FFD) … of a lens mount system is the distance from the mounting flange (the interlocking metal rings on the camera and the rear of the lens) to the film or image sensor plane. This value is different for different camera systems. Source Credit: Flange focal distance. Wikipedia.

For example, the FFD for Canon EF-mount is 44 mm and the FFD for Fujifilm X-mount is 17.7 mm. In order to make a Canon EF lens perform properly on a Fujifilm X-series camera body, an adapter must move the Canon lens 26.3 mm farther from the digital sensor. (44 mm – 17.7 mm = 26.3 mm)

Not surprisingly, when I remeasured the thickness of my Fringer EF-FX Pro II lens mount adapter it turns out to be closer to 26 mm than my original course estimate of 30 mm (cited below). The net result is the 17.7 mm FFD of my Fujifilm X-T3 combines with the 26.3 mm thickness of the Fringer adapter, resulting in an FFD of 44 mm — exactly the right FFD for the Canon lens to work properly on a Fujiflm X-series camera body!

It’s worth noting that “apparent magnification” is still a real thing when a camera lens designed for a “full-frame” camera is mounted on a camera with an APS-C size sensor. The image formed by the lens is exactly the same size regardless of the size of the digital sensor used to record the image, but a smaller part of the image is “seen” by an APS-C sensor than a full-frame sensor, resulting in the misperception that the image is magnified.

I hope this sets the record straight. Sincere apologies for any confusion I might have caused — I never heard of “flange focal distance” before I bought the Fringer adapter!

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[Post Update: From this point forward everything I wrote is incorrect. Is my face red, or what? I’ll explain further when I have a chance to use a desktop computer to edit this post.] … although the images appear to be magnified more than can be explained by this fact alone.

In the opinion of this author, the Fringer adapter functions like an extension tube. The adapter is ~3.0 cm (30 mm) in thickness. There aren’t any optics inside the adapter but it does move the lens 30 mm farther from the camera sensor. That, my friends, is an extension tube.

I used an online, interactive Macro Extension Tubes Calculator to estimate the effect of a 30mm extension tube on photos taken with the Canon MP-E 65mm macro lens at magnification ratios of 1:1 and 2:1. The calculator shows the magnification ratio increased from 1:1 to ~1.5:1 and 2:1 to ~2.5:1 respectively.

Macro Extension Tubes Calculator | 1:1 magnification ratio

The values for “new minimum focusing distance” are in millimeters, despite the fact that the second “m” only appears when you click an insertion point in the box and scroll to the right. The values for magnification ratio seem reasonable; the values for new minimum focusing distance, not so much.

Macro Extension Tubes Calculator | 2:1 magnification ratio

[End of segment with information that is incorrect.]

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Related Resources

Full-size photos of the preceding studio models are featured in the following blog posts. Those photos should help to give the reader a better sense of how much the subjects were magnified by the Fujifilm/Fringer/Canon MP-E 65mm macro lens rig.

• What is it? (published on 21 DEC 2020)
• What is it? It’s a toy Dimetrodon. (published on 23 DEC 2020)
• Toy dinosaur: focus-stacked composite image (published on 08 JAN 2021)
• Flange focal distance, by Wikpedia.
• Sensor Size and Magnification – correcting a common misunderstanding, by Allan Walls Photography (20:02). Fast-forward to 5:48. See also Sensor Size Matters – Part 1 (the Front Half) – A Demonstration (19:51).

Copyright © 2022 Walter Sanford. All rights reserved.

MYN – Eastern Amberwing exuvia (anal pyramid)

An Eastern Amberwing dragonfly (Perithemis tenera) exuvia was collected by Joe Johnston on 07 August 2019 along Aquia Creek at Channel Marker No. 34, Stafford County, Virginia USA.

The specimen is probably from either Family Corduliidae (Emeralds) or Family Libellulidae (Skimmers).

The rule of thumb for differentiating Corduliidae exuviae from Libellulidae is as follows: It’s probably Corduliidae if the cerci are at least half as long as the paraprocts; it’s probably Libellulidae if the cerci are less than half the length of the paraprocts.

65mm (3x magnification) | ISO 100 | f/8 | 1/200 s | 0 ev

Look closely at the full-size version of the preceding photo, showing a close-up of the anal pyramid at 3x magnification. Notice the cerci are approximately half as long as the epiproct and slightly less than half the length of the paraprocts. It’s a close call, but the latter field mark indicates Family Libellulidae (Skimmers).

A step-by-step identification guide (to the species level) will be published in a follow-up post. Stay tuned!

Related Resources

• MYN – Dragonfly exuvia (unknown species) [featuring face-head-dorsal and lateral views of the specimen]
• MYN – Unkown dragonfly exuvia (redux) [featuring dorsal and ventral views of the specimen]
• Perithemis tenera exuvia

Copyright © 2020 Walter Sanford. All rights reserved.

Composite image: “Generic Gomphid” (face)

A larva/nymph in the Family Gomphidae (Clubtails) was collected by Bob Perkins from the New River in southwestern Virginia. The larva died before it metamorphosed into an adult.

“Generic Gomphid” larva (preserved specimen) | New River, VA USA

An Ashy Clubtail dragonfly nymph was also collected by Bob Perkins. (The date and location where the specimen was collected are unknown.) The nymph was reared in captivity until it emerged on 21 March 2017 and metamorphosed into an adult female. This specimen is the exuvia from the nymph.

Ashy Clubtail (Phanogomphus lividus) | exuvia (face-head)

Although face-head of the “Generic Gomphid” and Ashy Clubtail look similar, they aren’t identical. More later after the specimen is keyed out carefully.

Related Resources

• Test shots: “Generic Gomphid”
• Composite images: “Generic Gomphid”
• Phanogomphus lividus exuvia

Tech Tips

13 photos were used to create the focus stack of the “Generic Gomphid.” A single focus point was positioned over select anatomical features; photos were taken at each point of interest.

The following equipment was used to shoot the composite image of the “Generic Gomphid”: Canon EOS 5D Mark II digital camera, in manual mode; Canon MP-E 65mm Macro lens (set for f/11 at ~2.5x); a Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and a single external flash set for “Slave” mode — a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Auto power-off was disabled for the camera and external flash units.

Adobe Photoshop CC 2017 was used to create the focus stack, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

“Generic Baskettail” (definitely not a Cruiser)

A larva/nymph in the Family Corduliidae (Emeralds) was collected by Bob Perkins on 02 December 2017 from a pond in Orange Park, Florida (USA). The larva died before it metamorphosed into an adult.

As you can see by looking at a close-up image of the face-head at 3x magnification, there is no horn on the face of the specimen. Therefore this individual is not a member of Family Macromiidae (Cruisers), as I speculated in my last blog post.

“Generic Baskettail” larva (preserved specimen) | face-head

Knowing the limits of our expertise

Although I still need to key out the specimen carefully, at this point I’m certain Bob is correct — the larva is a member of the Family Corduliidae (Emeralds). The question that remains unanswered is “Which genus/species?” We may never know the answer, as Bob and I have reached the limit of our experience and expertise.

I did a quick scan of Paulson’s [book], looking at the Emerald Family. Here, according to the range maps, are the possibilities for Orange Park [FL]. I believe you can see why I stopped at “generic basketttail.” Source Credit: Bob Perkins.

• Slender Baskettail (Epitheca costalis)
• Common Basketball (Epitheca cynosura)
• Prince Baskettail (Epitheca princeps)
• Mantled Baskettail (Epitheca semiaquea)
• Sepia Baskettail (Epitheca sepia)
• Florida Baskettail (Epitheca stella)
• Alabama Shadowdragon (Neurocordulia alabamensis)
• Umber Shadowdragon (Neurocordulia obsoleta)
• Fine-lined Emerald (Somatochlora filosa)
• Coppery Emerald (Somatochlora georgiana)
• Mocha Emerald (Somatochlora linearis)

What do you think the identity is? Most of the items in the preceding species list feature links to photos of odonate larvae/exuviae. See the links to BugGuide from the scientific names in the list.

Related Resource: Test shots: “Generic Baskettail?”

Tech Tips

Four (4) photos were used to create the preceding focus-stacked composite image. A single focus point was positioned over the face, between the antennae. At a magnification ratio of 3:1, it’s difficult to manually focus on a single point — the slightest movement around the macro rig changes focus unintentionally. A simple work-around for this problem is to take several shots of the same focus point and create a composite image of the photos.

The following equipment was used to shoot the preceding composite image: Canon EOS 5D Mark II digital camera, in manual mode; Canon MP-E 65mm Macro lens (set for f/16 at 3x); a Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and a single external flash set for “Slave” mode — a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier. A Sunpak LED-160 Video Light was used to add fill light to the top of the subject.

Auto power-off was disabled for the camera and external flash units.

Adobe Photoshop CC 2017 was used to create the focus stack, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

Composite image: Progomphus obscurus exuvia

The following focus-stacked composite image shows the exuvia from a Common Sanddragon (Progomphus obscurus) larva that was collected and reared by Bob Perkins.

I have 10s, maybe 100s, of Common Sanddragon exuviae in my collection, but have never seen one cleaner than this beautiful specimen. I didn’t realize P. obscurus larvae are so hairy!

Common Sanddragon (Progomphus obscurus) | exuvia (face-head)

Related Resource: More composite images: P. obscurus exuvia.

Tech Tips

11 photos were used to create the focus stack. A single focus point was positioned over select anatomical features, working from back-to-front; photos were taken at each point of interest.

The following equipment was used to shoot the preceding composite image: Canon EOS 5D Mark II digital camera, in manual mode; Canon MP-E 65mm Macro lens (set for f/11 at 3x); and Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and several external flashes set for “Slave” mode including Canon 580 EX- and Canon 580EX II Speedlites and a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Auto power-off was disabled for the camera and all external flash units.

Adobe Photoshop CC 2017 was used to create the focus stack, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

Test shot: Cordulegaster sp. larva

Bob Perkins collected and reared a larva/nymph from the Family Cordulegastridae (Spiketails). The larva died before it metamorphosed into an adult.

Test shots of this beautifully preserved specimen (Cordulegaster sp.) were taken using a relatively small aperture of f/16 for greater depth of field. The following photo is a “one-off,” that is, not a composite image.

Cordulegaster sp. larva (preserved specimen) | face-head

Odonates are aquatic insects. They spend most of their life as larvae that live in water; this stage of their life cycle can last from a few months to a few years. Finally, they emerge from the water and metamorphose into adults in order to reproduce; their offspring return to the water and the cycle begins again.

Most larvae go through 10-13 stages of development known as “instars.” The author lacks sufficient experience to identify the instar of this specimen, although it appears to be one of the later stages.

Related Resources

• Cordulegaster sp. larva (ventral view)
• Cordulegaster sp. larva (dorsal view)
• Odonate Exuviae – a hyperlinked list of identification guides to many species of odonate exuviae from seven families of dragonflies and three families of damselflies.

Tech Tips

The following equipment was used to shoot the preceding photo: Canon EOS 5D Mark II digital camera, in manual mode; Canon MP-E 65mm Macro lens (set for 3x); and Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and several external flashes set for “Slave” mode including Canon 580 EX- and Canon 580EX II Speedlites and a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier. A Sunpak LED-160 Video Light was used to light the underside of the white plastic posing “stage.”

Auto power-off was disabled for the camera and all external flash units.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

Top 10 Photos of 2018

The following gallery shows 18 finalists for my “Top 10 Photos of 2018.” The photos are presented in reverse-chronological order beginning in September 2018 and ending in February 2018.

As you will see, I declare 2018 is/was unofficially “Year of the Sable Clubtail (S. rogersi).”

No. 1

20 SEP 2018 | Fairfax County, VA | Pandora Sphinx moth

No. 2

23 AUG 2018 | Occoquan Bay NWR | Osprey (male, plus prey)

No. 3

10 AUG 2018 | Occoquan Bay NWR | Calico Pennant (female)

No. 4

19 JUL 2018 | Fairfax County, VA | Black-shouldered Spinyleg (female)

No. 5

17 JUL 2018 | Huntley Meadows Park | Mocha Emerald (male)

No. 6

05 JUL 2018 | Fairfax County, VA | Sable Clubtail (female)

No. 7

24 JUN 2018 | Occoquan Regional Park | Widow Skimmer (immature male)

No. 8

24 JUN 2018 | Occoquan Regional Park | Ebony Jewelwing (mating pair)

No. 9

12 JUN 2018 | Fairfax County, VA | Sable Clubtail (male)

No. 10

08 JUN 2018 | Fairfax County, VA | Sable Clubtail (male)

No. 11

06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

No. 12

23 APR 2018 | Hemlock Overlook Regional Park | Virginia Bluebells

No. 13

23 APR 2017 | HORP | Springtime Darner (male)

No. 14

23 APR 2018 | Hemlock Overlook Regional Park | Horseshoe Trail

No. 15

29 MAR 2018 | Ashy Clubtail (Phanogomphus lividus) | exuvia (face-head)

No. 16

06 MAR 2018 | Fawn Darner (Boyeria vinosa) | exuvia (face-head)

No. 17

13 FEB 2018 | Gray Petaltail (Tachopteryx thoreyi) | exuvia (face-head)

No. 18

03 FEB 2018 | Tiger Spiketail (Cordulegaster erronea) | exuvia (face-head)

Editor’s Note: The following location codes are used in some photo captions, shown above.

• HMP = Huntley Meadows Park
• HORP = Hemlock Overlook Regional Park
• JMAWR = Jackson Mile Abbott Wetland Refuge
• MNWP = Mason Neck West Park
• MRA = Meadowood Recreation Area
• OBNWR = Occoquan Bay National Wildlife Refuge
• WP/DC = Wickford Park/Dogue Creek

Copyright © 2019 Walter Sanford. All rights reserved.

New odonate exuviae in 2018 (by family)

2018 is the year I got serious about macro photography of odonate exuviae. I bought lots of new photography gear and spent hours learning to use it, and spent more time refining my workflow for creating focus-stacked composite images.

I am blessed to have several mentors who have patiently taught me a lot about identification of odonate exuviae, and many friends who have kindly collected and shared specimens with me. Sincere thanks to Sue and John Gregoire, Richard Orr, Michael Powell, Bob Perkins, Mike Boatwright, Andy Davidson, and Joe Johnston.

Dragonflies (Order Anisoptera)

Family Aeshnidae (Darners)

Boyeria vinosa exuvia (Fawn Darner)

• Test shots: Aeshna umbrosa exuvia (Shadow Darner)
• Test shots: Brachyton pratense exuvia (female) [Hairy Dragonfly]

Family Cordulegastridae (Spiketails)

• Cordulegastridae exuvia

Cordulegaster erronea exuvia (Tiger Spiketail)

Family Corduliidae (Emeralds)

• Epitheca princeps exuvia [another Prince Baskettail]
• Helocordulia uhleri exuvia [Uhler’s Sundragon]
• Test shots: Unknown odonate exuvia [Downy Emerald (Cordulia aenea)]

Family Gomphidae (Clubtails)

• Erpetogomphus designatus exuvia [Eastern Ringtail]
• Ophiogomphus aspersus exuvia [Brook Snaketail]
• Ophiogomphus incurvatus exuvia [Appalachian Snaketail]
• Ophiogomphus incurvatus head shots [Appalachian Snaketail]
• More composite images [Appalachian Snaketail]

Phanogomphus lividus exuvia [Ashy Clubtail]

• Stenogomphurus rogersi: Miraculous metamorphosis [Sable Clubtail] New!
• Stenogomphurus rogersi exuvia [Sable Clubtail] New!
• Test shots: Stylogomphus albistylus exuvia [Eastern Least Clubtail] New!
• More test shots: Stylogomphus albistylus exuvia [Eastern Least Clubtail] New!
• Test shots: Stylurus sp. exuvia [possible Laura’s Clubtail] New!
• Stylurus plagiatus exuvia [Russet-tipped Clubtail] New!
• Test shots: Stylurus plagiatus exuvia [Russet-tipped Clubtail] New!
• Stylurus scudderi exuvia [Zebra Clubtail] New!

Family Libellulidae (Skimmers)

• Calico Pennant exuvia composite image [Celithemis elisa]
• More Calico Pennant exuvia composite images [Celithemis elisa]
• Previews of coming attractions [Slaty Skimmer (Libellula incesta)]
• Test shots: Erythemis simplicollis exuvia [Eastern Pondhawk]
• Test shots: Libellula luctuosa exuvia [Widow Skimmer]
• Test shots: Pachydiplax longipennis exuvia [Blue Dasher]
• Test shots: Pantala flavescens exuvia [Wandering Glider]

Family Macromiidae (Cruisers)

• Macromia alleghaniensis exuvia [Allegheny River Cruiser]
• Swift River Cruiser exuvia [Macromia illinoiensis]

Family Petaluridae (Petaltails)

Tachopteryx thoreyi exuvia [Gray Petaltail]

• Test shots: Tachopteryx thoreyi exuviae [Gray Petaltail]

Damselflies (Order Zygoptera)

Family Calopterygidae (Broad-winged Damselflies)

• American Rubyspot damselfly exuvia
• Hetaerina americana exuvia [American Rubyspot]

Related Resources: Odonate Exuviae.

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Next post: New Life List additions in 2018 (odonates).

Copyright © 2018 Walter Sanford. All rights reserved.

Do-over

The Backstory

An Ashy Clubtail dragonfly (Phanogomphus lividus) nymph was collected by Bob Perkins. (The date and location where the specimen was collected are unknown.) The nymph was reared in captivity until it emerged on 21 March 2017 and metamorphosed into an adult female. This specimen is the exuvia from the nymph. P. lividus is a member of the Family Gomphidae (Clubtails).

A focus-stacked composite image was created from 39 photos focused on the face and head of the exuvia. I had relatively little experience using Adobe Photoshop to make focus stacks when I created the first iterations of the Ashy Clubtail composite image. I was never satisfied completely with the final output, so I decided to do a do-over.

After…

The updated version of the composite image was created using my “Latest focus stacking workflow.”

Ashy Clubtail (Phanogomphus lividus) | exuvia (face-head)

Before…

The version that I published in late-March 2018 was created using the RAW photos (CR2) from my Canon digital camera, without any post-processing. I tried to adjust the white balance and color palette of the resulting composite image, but was unable to get the “look” I wanted. The image is probably over-sharpened too.

Ashy Clubtail (Phanogomphus lividus) | exuvia (face-head)

Which version do you prefer?

I know the version I like more. Which do you prefer, After or Before?

Tech Tips

The preceding images are composites of 39 photos taken using the following equipment: Canon EOS 5D Mark II digital camera, in manual mode; Canon MP-E 65mm Macro lens (manual focus only, set for 3x magnification); and Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and Canon 580 EX- and Canon 580EX II Speedlites set for “Slave” mode.

Adobe Photoshop CC 2017 was used to focus stack the photos and post-process the final output.

According to the “Focus Stacking Step Size Calculator” embedded in the “Focus Stacking” Web page, the “safe step size” is 0.213 mm for an aperture of f/11 at 3x magnification using a full-frame DSLR. That’s right, 0.213 mm! The safe step size is the incremental distance at which the in-focus areas of two photos overlap. The ruler on the inexpensive focus rail that I use is marked in millimeters only, so I attempted to move the focus rail in tiny increments in two passes: one pass moving from front-to-back; and a second pass from back-to-front.

Copyright © 2018 Walter Sanford. All rights reserved.

Macromia alleghaniensis exuvia

Michael Boatwright, founder and administrator of the Virginia Odonata Facebook group, collected an odonate exuvia on 07 June 2018 along either Little Otter Creek or Otter Creek near the place where both creeks are distributaries of Otter Lake in Amherst County, Virginia USA.

A two-step process was used to identify the genus and species of the exuvia.

1. Determine the family.
2. Determine the genus and species.

Step 1. Family

First, determine the family of the specimen. For reference, watch the excellent Vimeo video, Identifying dragonfly larva to family (8:06). Here’s the decision tree used to identify the exuvia as a member of the Family Macromiidae (Cruisers).

• The specimen has a mask-like labium (prementum) that covers the face, as shown in Photo No. 1, characteristic of four families of odonates: Cordulegastridae (Spiketails); Corduliidae (Emeralds); Libellulidae (Skimmers); and Macromiidae (Cruisers).
• The teeth on the margins of the labium have a regular pattern. (The pattern reminds me of a “spork.”)
• Its eyes are small, wide set, and stick up.
• Image No. 2 shows there is a horn on the face-head, characteristic of Macromiidae.

Photo No. 1 shows a face-head view of the exuvia, magnified approximately three times life size (~3x).

No. 1 | Macromia alleghaniensis | exuvia (face-head)

Image No. 2 shows the top of the head of the exuvia, magnified approximately three times life size (~3x). Notice the prominent horn on the face.

No. 2 | Macromia alleghaniensis | exuvia (head-horn)

Step 2. Genus and species

Two dichotomous keys found on p. 27 of Identification Keys to Northeastern Anisoptera Larvae, compiled by Ken Soltesz, were used to determine the genus and species of the exuvia. Field marks that match this specimen are highlighted in boldface green text. Three boldface green asterisks (***) are used to highlight the thread for identification of this specimen.

Key to the Genera of the Family Macromiidae

***1b. Lateral spines of abdominal segment 9 do not reach to rearward level of tips of inferior appendages [paraprocts]; Sides of head somewhat convergent behind eyes to pair of low turbercules on hind angles; Lateral setae of labium = 6; Small dorsal hook on segment 10. [Macromia]

A small dorsal hook on abdominal segment 10 is characteristic of Genus Macromia.

No. 3 | Macromia alleghaniensis | exuvia (dorsal-lateral)

Look closely at the full-size version of Image No. 4. Notice the little “nub” on abdominal segment 10 (S10), below the underside of the dorsal hook on abdominal segment nine (S9). The same structure is labeled with a white question mark in Image No. 3.

No. 4 | Macromia alleghaniensis | exuvia (dorsal-lateral)

The lateral spines of abdominal segment 9 (S9) do not reach rearward to the tips of the inferior appendages (paraprocts).

No. 5 | Macromia alleghaniensis | exuvia (dorsal)

Key to the Species of Macromia

1a. Lateral spines of abdominal segments 8 and 9 directed straight to rearward. [illinoiensis]

***1b. Lateral spines of abdominal segments 8 and 9 incurved, especially 8. [alleghaniensis]

The lateral spines of abdominal segments 8 and 9 (S8-9) are incurved, especially segment 8 (S8), indicating this species is alleghaniensis.

No. 6 | Macromia alleghaniensis | exuvia (ventral)

This individual is probably a male, as indicated by what appear to be vestigial hamules located on the ventral side of abdominal segments two and three (S2-3).

Summary

A prominent horn on the face is a key field mark for the Family Macromiidae (Cruisers), a small dorsal hook on abdominal segment 10 is one characteristic of the Genus Macromia, and the lateral spines of abdominal segments 8 and 9 (S8-9) are incurved, indicating the species is alleghaniensis. Therefore this specimen is an Allegheny River Cruiser dragonfly (Macromia alleghaniensis).

Bonus Gallery

No. 7 | Macromia alleghaniensis | exuvia (face-head)

No. 8 | Macromia alleghaniensis | exuvia (dorsal-lateral)

No. 9 | Macromia alleghaniensis | exuvia (dorsal)

Related Resources

• Macromiidae larvae/exuviae are horny
• Identification Keys to Northeastern Anisoptera Larvae, compiled by Ken Soltesz
• Odonate Exuviae

Tech Tips

The following equipment was used to shoot Photo/Image No. 3-9: Canon EOS 5D Mark II digital camera, in manual mode; Kenko 20mm macro automatic extension tube; Canon EF100mm f/2.8L Macro lens (set for manual focus); Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and Canon 580 EX- and Canon 580EX II Speedlites set for “Slave” mode. Photo/Image No. 1 and 2: Canon MP-E 65mm Macro lens (manual focus only, set for ~3x magnification) plus the multiple-flash setup.

Image No. 2-8 are focus-stacked composite images created and annotated using Adobe Photoshop CC 2017: Image No. 2 (eight photos); Image No. 3 (six photos); Image No. 4 (four photos); Image No. 5 (five photos); Image No. 6 (five photos); Image No. 7 (seven photos); Image No. 8 (seven photos).

Copyright © 2018 Walter Sanford. All rights reserved.