Monthly inventory

Eastern Amberwing (Perithemis genera). Boca Raton, FL, October 3, 2014.

October is a month of transition here in south Florida. The wet days of the rainy season start to taper off, giving way to the first few cooling breaths of our short-lived autumn, eventually to be followed by the drier and steadier days of our wintertime dry season (which usually arrives around November). That doesn’t mean it won’t rain; we still get appreciable rainfall in this last month of the wet season, but the rains are punctuated by spells of drier, cooler weather, that is much welcomed after the long, hot days of summer.

The first few days this month were typical late summer/early fall, with warm, humid weather. The only thing atypical about it was the lack of easterly breeze, at least in the early hours, making photography relatively easy. On the first weekend of the month, a cool front blew through, lowering the 8 a.m. temps from the high 70s/low 80s to the mid-60s. Yay! It also made photography even easier, pushing the energy budget of the insects down a mite. Whether for that reason or some seasonal effect (late emergence, early migration, what have you), I was able to add a Green Darner (only seen once before in the four years we’ve been on this site) and the two bee species only after the cool front. Whether they were here and I just missed them before the shift in the weather, I don’t know.

These questions mean it’s time to get outside on a bit more regular basis, to attempt to answer them! This year I was particularly motivated to get outside in October, because I recently joined the North American Butterfly Association, after years of telling myself “I really should join NABA.” They’re a nonprofit organization dedicated to education, conservation, and scientific research on—you guessed it!—butterflies! They have a butterfly garden certification program that allows you to send them a brief inventory of the nectar plants (flowers) and larval host plants (caterpillar food) in your yard, along with a check or other payment, and get a lovely sign to post in your yard:


While the certification process is not onerous (seriously—all I had to do was indicate the size of the plot, the management practices, and list three nectar plants and three host plants, no pictures, no records, nothing), it did get me to thinking about taking inventory in the yard in a new way.

So that’s what I did. First, I made a table of all the butterfly plants in my yard (nearly 30 different species!). That done, I decided I needed to do a bit more. So I started another spreadsheet (oh, the joy!) to record my wildlife sightings on a monthly basis. It’s a bit like the yard list that birders do, but like a true geek, I decided that it needed to be a bit more comprehensive, including month and year, rather than just as a checkmark on a bare list.

I went as far back as 2012 in my photo archives to populate the list with a bit of scattershot historical data, but going forward I’ll be updating it as often as I can, and as often as I can get decent pictures. Right now it lists only a couple of insect orders: Odonata (damsel- and dragonflies) and Lepidoptera (butterflies, moths, skippers). As and when I find time I’ll update the lists, at least to include the Hymenoptera (ants, bees, wasps).

This gives me an incentive to get out and see what’s new, who’s more abundant now, who’s absent. And I will no longer have to rely solely on my wretched memory to know when certain species are present or absent, and with what kind of frequency.

As advertised, the first few mornings of October 2014 were lovely—good light, very little wind, not yet hotter than blazes. Over those first few days I’ve documented the following insects and spiders in the garden:

    • 3 species of damselfly (the usual suspects: two fork tails [Ischnuras ramburii and hastata] and our ever-present Everglades Sprite [Nehalennia pallidula]); here’s a picture of the Rambur’s Forktail from September, but they look the same in October:
Rambur's Forktail (Ischnura ramburii). Boca Raton, FL, September 22, 2014.

Rambur’s Forktail (Ischnura ramburii). Boca Raton, FL, September 22, 2014.

    • 6 species of dragonfly (Band-winged Dragonlet, Little Blue Dragonlet, Blue Dasher, Carolina Saddlebags, Halloween Pennant, and a new one for the yard, Eastern Amberwing!)
Eastern Amberwing (Perithemis genera). Boca Raton, FL, October 3, 2014.

Eastern Amberwing (Perithemis genera). Boca Raton, FL, October 3, 2014.

    • The usual species of butterfly (Zebra Heliconian, Gulf Fritillary, Cassius Blue, Cloudless Sulphur, Giant Swallowtail). Thanks to the cooler weather I was able to get up close and personal with a Cloudless Sulphur butterfly (Phoebis sennae), normally far too swift and fluttery for me to capture on “film.” Yay, cooler weather!
Cloudless Sulphur (Phoebis sennae). Boca Raton, FL, October 5, 2014.

Cloudless Sulphur (Phoebis sennae). Boca Raton, FL, October 5, 2014.

    • An Ichneumon wasp, genus Anomalon
Ichneumon wasp, genus Anomalon. Boca Raton, FL, October 2, 2014.

Ichneumon wasp, genus Anomalon. Boca Raton, FL, October 2, 2014.

      • The usual quartet of large south Florida garden spiders (Gasteracantha cancriformis, Argiope argentata, A. trifasciata, and Leucauge argyra). Pictured is the very common (elsewhere, rare-ish in my yard) Banded Garden Spider, Argiope trifasciata. The smaller spider on the opposite side of the web from the large female is the small male. He no dummy!
Banded garden spider (Argiope trifasciata). Boca Raton, FL, October 1, 2014.

Banded garden spider (Argiope trifasciata). Boca Raton, FL, October 1, 2014.

    • Several syrphid flies (also known as “hoverfly” or “flower fly”): Toxomerus marginatus and T. boscii.
A flower fly, Toxomerus marginatus. Like many tiny insects, this one has no common name.

A flower fly, Toxomerus marginatus. Like many tiny insects, this one has no common name. Boca Raton, FL, October 1, 2014.

      • A pair of unidentified sarcophagid flies (also called “flesh flies”)
      • A “leaf beetle,” Chalepus sanguinicollis:
Leaf beetle, Chalepis sanguinicollis. Boca Raton, FL, October 4, 2014.

Leaf beetle, Chalepus sanguinicollis. Boca Raton, FL, October 4, 2014.

    • One of our two yard-normal halictids (sweat bees), Halictus poeyi
    • A leaf-cutter (megachilid) bee, Megachile petulans, demonstrating a very stout abdomen and a tiny waist more reminiscent of a wasp than a bee—looks a bit like a little grenade or something! It also has a very loud buzz; much more noticeable than the sweat bees or honeybees that cruise through here most of the time:
A leafcutter bee (Megachilid petulans). Boca Raton, FL, October 5, 2014.

A leafcutter bee (Megachilid petulans). Boca Raton, FL, October 5, 2014.

I don’t know whether this data will ever be useful to anyone, but it’s a fun project. And when you find a new species for your yard, it can be really exciting. Getting a reasonable picture of one of those tiny little flower flies (T. marginatus in this case) encouraged me to comb through my past photos to get a few more IDs from the good folks at

So I guess it’s misleading to call this an “inventory”; for now it’s more of a snapshot, taken from the limited perspective of a few short hours in the “field.” Nevertheless, it’s an interesting snapshot. Speaking of which, hope you enjoyed these snapshots of the insect and arachnid life in a small suburban yard in south Florida!

You never know what you mind find when you get out into nature—even if it’s only right outside your door.

Next up: the second half of the month, including a new butterfly species for the yard, Martial Scrub-Hairstreak (with photos) and the return of the hummingbirds (without photos).

Dragonflies: eyes and a face

Blue Dasher (Pachydiplax longipennis). Boca Raton, FL, May 7, 2013.

Those of you who grew up in the 1980s might remember Billy Idol’s rock ballad “Eyes Without a Face.” It’s a catchy little song that owes its title to Jean Redon’s grisly horror novel Les yeux sans visage, which was adapted to the big screen back in 1962 and featured serial murders, a doctor’s daughter in an eerie face mask, and lots of gore, although the film version apparently toned it down quite a bit. Billy Idol’s sung version cast off all the gore and just went for despair and angst with strong guitars and a catchy rock beat. Nevertheless, if you’ve heard the song, you probably remember it, in part because of the simplicity of the title (and the awesome backup vocals by Perri Lister, in French and English).

A lot of you might think that the dragonfly, with its enormous eyes, can also be described by that pithy little phrase. After all, their eyes are enormous, taking up most of their head. But, as you can see below, while it might make for a nice catchy song, it doesn’t describe the dragonfly very well. Dragonflies definitely have a “face.”

Blue Dasher (<i>Pachydiplax longipennis</i>). Boca Raton, FL, May 7, 2013.

Blue Dasher (Pachydiplax longipennis). Uncropped version from which the face detail was taken. Boca Raton, FL, May 7, 2013.

The dragonfly in question is a Blue Dasher (Pachydiplax longipennis), one of the most widespread and abundant dragonflies in North America. Apparently its larvae are able to tolerate a wide range of water quality, and compete in both fishful and fishfree ponds, which gives them a huge range of habitat in which to reproduce. They also make wonderful photographic subjects, often sitting nice and still to let the careful photographer get as close as his or her equipment will allow. (If you have a macro lens, that’s pretty darn close. Close enough to be able to crop an image and give you a little lesson in dragonfly facial anatomy.)

This picture was taken in my normal study site, aka my backyard, from about a foot and a half away; when I tried to pull in even tighter, the dasher lived up to its name and dashed away (flying of course; dragonflies, despite having six legs like most other insects, can’t walk). But when your camera has way too many megapixels (actually, that hardly matters at all) and you’re able to hold it nice and steady to get a sharp image (that’s the important bit), you can blow up a crop to just about whatever size you please. So I decided to spend a few minutes in Photoshop to give you all a little roadmap of the dragonfly’s facial anatomy.

Hover your cursor over the image to see what each structure is.

Blue Dasher face

The “face” of the dragonfly, starting from the very bottom, consists of mandibles (not labeled, barely visible as dark smudges at bottom) that are usually concealed under the labrum, or “lower lip” (labeled). The clypeus is composed of the “top lip,” or postclypeus, and the anteclypeus, which is in what would be the “tongue” position were this a human face. Above the clypeus is the frons, from which arises the vertex, which serves as the anchor for the three ocelli, or simple eyes. The antennas arise from the base of the vertex as well. At the top of the “face,”the two eyes meet; the “joint” or seam is called the occiput.

Now that we’ve got the unfamiliar parts of the dragonfly face out of the way, let’s go back to that most familiar, and most prominent, feature of the dragonfly head: the huge compound eyes, with thousands upon thousands of ommatidia, or facets, that make up this complex visual apparatus. If you look closely, you’ll see that the larger facets are all on the top of the eye, the part that’s colored deep red. The smaller facets are on the bottom half, the part that’s colored blue-gray and has the black “pseudopupils.”

Most dragonflies that you’re likely to see fly during the day (the twilight-flying dragonflies are quite a bit less common in most people’s experience) and have excellent color vision. Our own eyes have three different color-sensitive retinal proteins, called opsins, that give us the familiar red-green-blue mix of color perception. (Those RGB  color values don’t correspond exactly to the peak sensitivity of each opsin, but, meh… close enough). Diurnal (day-flying) dragonflies, on the other hand, have as many as five opsins in their visual reception apparatus, giving them access to a much greater range of the electromagnetic spectrum.

What’s interesting is the arrangement of the ommatidia with respect to the part of the spectrum they’re sensitive to. Recall the visual spectrum mnemonic: ROYGBV. That is, red-orange-yellow-green-blue, in ascending  wavelength order. Red has the longest wavelength, while blue, violet, and, beyond the violet, ultra-violet, have the shortest wavelengths:

Visible spectrum. Image from Wikipedia.

Those larger facets on the top of the dragonfly’s eye? They are sensitive to UV light and blue light (on the right in the image above). The smaller ommatidia on the bottom half of the eye? They’re specialized for longer-wavelength light, like orange or green.

As anyone who’s tried to get close to a dragonfly, whether to capture it or just its image, those eyes are extraordinarily capable of detecting movement. That great visual acuity appears to be related to the presence (and direction) of  the pseudopupil (the dark region in the light blue-gray portion of the eye in the photo above). They seem to indicate the insect’s fovea, or zone of greatest visual acuity.

Land and Nilsson (2012) write that “perhaps the most useful feature of the pseudopupil [to the entomologist, if not to the insect itself] is that one can use it to measure inter-ommatidial angles. If one rotates an insect’s head through a degrees, and the pseudopupil appears to move across b facets, then the inter-ommatidial angle is a/b degrees. Variations in inter-ommatidial angle in different planes, and in different regions of the eye, can be mapped in this way, revealing how the eye is is organized to make the most of its limited visual acuity.”

Mapping the organization of the dragonfly eye is exactly what Truman Sherk did in a classic series of articles in the mid-1970s, tracing the development of dragonfly eyes from larva through adult animal, mapping the foveae and relating it to predation style. In the photo above you can see the pseudopupil looking directly at the camera, “anteriorly” as the scientists like to say. That is, directly in front of the animal.

In the example below, though, you can see lots of “accessory” pseudopupils:

Blue Dasher (<i>Pachydiplax longipennis</i>) displaying multiple accessory pseudopupils.

Blue Dasher (Pachydiplax longipennis) displaying multiple accessory pseudopupils.

That is, in addition to the main, large pseudopupil, you can see several other dark spots; each of these is also a pseudopupil and indicates a zone of great visual acuity. According to Sherk, “the size and shape of the accessory pseudopupils [appear] to be related to the geometrical arrangement of the corneal facets, the slight curvature of the individual facets, and to the regional radius of curvature of the cornea. The contrast between the accessory pseudopupils and the surface [appears] to be related to the maturity of the cells between the cornea and the rhabdom.”

That might be a bit more than you wanted to know about the dragonfly and its face, but next time you see a dragonfly buzzing off when you so much as twitch a muscle in its direction, you might have a deeper appreciation for what makes that response possible: those amazing eyes.


Corbet, P. (1999). Dragonflies: Behavior and Ecology of Odonata. Ithaca: Cornell UP

Land, M. F., and D.-E. Nilsson. (2012). Animal Eyes, 2d ed. New York: Oxford UP.

Needham, J. G., and M. J. Westfall. (1955). A Manual of the Dragonflies of North America (Anisoptera).  Berkeley: U of California P.

Paulson, D.R.  (2011). Dragonflies and Damselflies of the East. Princeton, NJ: Princeton UP.

Sherk, T. E. (1978). Development of the compound eyes of dragonflies (Odonata). III. Adult compound eyes. J. Exp.Zool 203:61-80.

When dragonflies don’t…


fly, that is.

This morning when Eric and I went outside to plant some basil (yes, November is the start of herb-growing season here in south Florida), we noticed a dragonfly on the wall of the house that wasn’t moving very much. One of its wings was at an odd angle:

On closer inspection, it looked like this Blue Dasher (known to odonate enthusiasts as Pachydiplax longipennis) had sustained some kind of damage to the thorax; perhaps the little gal flew into a window or something:

Here’s a detail of that same shot:

The ichor on the thorax is what makes me think this is injury, rather than simply a problem that occurred during emergence. Most emergence problems result in a dragonfly that can’t fly at all, not one that has a perfectly fine-looking wing held at the wrong angle.

And as I’ve read, dragonflies can fly with only three wings. And this young lady proved it: after remaining patient through many close-ups for me, this little lady flew off and wasn’t seen again. But not before giving me the best photo of a dragonfly face I’ve gotten to date:

Hope you find her as beautiful as I do!


A really bad day for a Regal Darner


Think you’re having a bad day? At least you’re not upside down in a swimming pool:

This dragonfly, with the noble name Regal Darner (Coryphaeschna ingens), was still beating its wings, so I scooped it out of the pool and put it on the deck, where it appeared rather bedraggled.

It was disoriented and appeared frantic to remain near the water; perhaps this head shot, in which you can see how damaged its left eye is, explains why:

And, as it turns out, my rescue attempt wasn’t very successful. As soon as I turned my back, I saw a lizard streak out from hiding and scoop it up; here is all that’s left of this beautiful insect:

These throwaway bits that the lizard didn’t want to bother ingesting provide perfect clues to the sex of the departed insect, though: female. The u-shaped hook on the bottom of segment 9 is called a stylus, which is believed to enable the dragonfly to place its eggs with great precision in whatever substrate it prefers.

The long “tails” at the end of the abdomen are called cerci; their presence, along with the green coloration of the eyes, indicates that this was a juvenile darner. As female darners age, oviposition or simple wear and tear cause these appendages to break off; long tails usually means young bug.


The genus, Coryphaeschna, is a compound word, formed from the Greek aechma, “spear,” and another Greek word, corypho, “head, top”: thus, “spearhead.” The French entomologist Jules Pierre Rambur described this species, the type specimen for the entire (now obsolete) genus Aeshna, in his 1842 Histoire naturelle des insectes, part of the Suites à Buffon. The specific name, ingens, is Latin for “vast, huge, great, immoderately large,” and describes the size of this dragonfly quite well.

Hope your day is better than this little lady’s was!

Blue Dasher bonanza [updated Feb 2012]


It was a lot of fun sitting out back proofreading this morning. The humidity is down, so the temperature, while “the same” according to the thermometer as it was before T.S. Nicole/T.D. 16 blew through, is a lot more livable. (It’s starting to feel like fall; the typical way it arrives here in south Florida: an inch at a time, with lots of backsliding and sweating a la summer.)

I’m not sure whether it’s connected to the nicer weather, but we had what I would almost call an infestation of dragonflies today: mostly Blue Dashers, but a few larger skimmer species as well. They were dripping from every available perch in the backyard: shrubs, trees, telephone wires. They were in the oak trees in the front yard, on the streetlight (boo! hiss! light pollution!) wires. It was astonishing!

Here are a couple of photos (male Blue Dashers, Pachydiplax longipennis) that turned out nicely:

If you want to see what a real swarm of dragonflies looks like, or find out more about how and why they swarm, see this post on the dragonfly woman’s website. All I know is today it was a lot of fun to be a backyard naturalist!

[UPDATE: I’d been meaning to look up the origin of this species’ name, which I keep misremembering as Brachydiplax. Turns out that pachy, which we all recognize from pachyderm, is Greek for thick. Plax, placos, is Greek for plate, tablet: anything wide and flat. Longipennis is Latin for long-winged (yes, 2 n’s, people). So this species’ name translates to “thick double-plated long wings.” I’m not really sure if Burmeister, who named it in 1839, had that exact meaning in mind, but, since I haven’t been able to get to a source telling me otherwise, this is what it means to me. If anyone out there has a better translation for me, I’d love to hear it.

If you go to Needham and Westfall (1955; thanks, M!) or Needham, Westfall, and May (2000; I wish!), you can find this: “the genus is easily recognized by a single venational character: the single crossvein under the distal end of the [ptero]stigma has a vacant space, about as long as four normal cells, between it and the four postnodal crossveins of the second row. … Length of wings not remarkable, though the specific Latin name makes reference to it. Shortness of abdomen in female gives impression of long wings.”

So the generic name might refer to that long empty spot under the pterostigma; I’m not sure if that’s what Burmeister had in mind, but it’s my working hypothesis.]

[Update, February 2012: Thanks to the North American Odonata checklist of Dunkle and Paulson, I can now update the etymology of the generic and specific names: Pachydiplax means “thick Diplax,” referring to the “stout female abdomen in comparison with members of the old libellulid genus Diplax”; “longipennis” does indeed mean long-winged, but D&P specify that it is in relation to the relatively short female abdomen.” It’s so nice to have an authoritative starting point for etymological information about these creatures!]

A darner from a couple of years ago: Gynacantha nervosa

A two-year-old mystery has come closer to being solved, thanks to the friendly folks at You see, back when Tropical Storm Fay blew into town on August 18, 2008, a large dragonfly took shelter on our porch:

It is long and slender-bodied, almost like a knitting or darning needle. I can recall that it was quite large; I don’t think I’d ever seen such a large dragonfly so close before. The eyes are huge; see how there’s no “top of the head” on this guy? There’s eyes, and nothing else. And as you can see, it was hanging vertically from the brick face surrounding the giant picture window that I was in the process of covering with hurricane shutters at the time.

All of these traits (except for the hurricane shutters, of course) point to this dragonfly being one of the eight darner species (family Aeshnidae) in Florida. Here is Dunkle’s description of the family:

The darners are long and slender-bodied, like a darning needle, and they include the largest Florida Dragonflies. Their eyes are very large and meet in a seam on top of the head. In most species scars can be seen on the eyes of a female where a male has held her during mating. Females have an ovipositor with blades, as in the Petaltails. Darners hang vertically on a perch whether it is a vertical stem or a horizontal twig [or in this case a brick-face wall]” (20).

Unfortunately I wasn’t aware of the importance of the thorax in distinguishing among several possible species in different genera, Comet Darner (Anax longipes), Cyrano Darner (Nasiaeschna pentacantha), and Regal Darner (Coryphaeschna ingens), but I’m pretty sure that this is the latter species. [UPDATE 9/10/10: Upon further review, it looks like Twilight Darner (Gynacantha nervosa) is a better match for this individual. The thoracic markings are indistinct, which fits G. nervosa much better than C. ingens.]  In the first place, the friendly folks at think it’s likely to be. In the second place, most of the photos I’ve seen of Comet Darners show “blotches” on the abdomen, rather than the “dots” I see on this one. Cyrano darner has those dots, but, according to the checklist from Odonata Central, has not been recorded in Palm Beach County, while Regal Darner has been. (Not that going by the book is a sure guide, particularly with a tropical storm that could be blowing things in from far away, but it’s another piece of the puzzle.)

Now, two years later, I sure wish I’d taken more photos, but at the time I was more concerned with putting the hurricane shutters on than I was with narrowing down the ID of the animal. I was pretty sure the photos I had would be conclusive. As it turns out, they are simply not good, from any angle, because I didn’t know what I should have been looking for. That’s why relying on photography for a positive ID is a problem: if the field mark you need is not in focus, you’re out of luck. (On the flip side, it’s a good learning tool: now I know to try to get good pictures of the thorax for any darner, so we can use the markings there to help figure out what it might be.)

Here’s the other side, of the animal, with a better view of the tail:

In this view, it’s a bit easier to see the ovipositor:

Those two strips hanging down from the very end of the tail, on the left of the picture (top, or dorsal side)? That’s not the ovipositor; those are called cerci, or terminal abdominal appendages, and both sexes have them. On a good picture of this insect, like this one, you can see that they are quite long; the ones on this lady are pretty short. No, the ovipositor is a bit higher up, on the right of the picture (ventral, or bottom, side of the abdomen). [UPDATE 9/10/10: the ovipositor is above the last abdominal segment, 10; on that segment (S10), you can see, in Dunkle’s words and in that photo of the tail, “2 spines on the underside…which are used during egg deposition. [They] form a fulcrum when she uses her ovipositor blades to lay eggs in soil” (28).] So don’t get confused if you see a male dragonfly with terminal appendages. That’s perfectly normal. A male dragonfly with an ovipositor, though—that would be big news.

So, to make a long story short, if you want to take better nature photos, learn more about your subjects, so you can know what it is you’re trying to capture. Then see if there’s a way to make it pretty. I have a long way to go on both fronts… But it’s a fun road to travel!

A dragonfly in the oak tree

I think everyone likes to learn things. I know I do. Last week when I spotted a dragonfly perched in the oak tree out front, I grabbed my camera and binoculars to investigate a bit further. Perched Dragonflies are Much Easier to Identify than Flying Dragonflies.

There are 169 species records in Florida now, but these include both the zygoptera (damselwings) and the anisoptera (dragonflies); I’m not sure what the breakdown between the two groups is. [UPDATE: According to this website, there are now 123 dragonfly species in the state, and 47 damselfly species, which brings us up to 170 as of 2007. Hmmmm…..] Back in 1989, when Sidney Dunkle published his groundbreaking field guide to the state, he included 86 dragonfly species (94 with Bermuda and the Bahamas included); I wonder if there have been enough changes to the list to require a new field guide to Florida? [John Epler’s 123 species certainly seems to argue for an update.]

Whichever number you like, 169 or 93,  it’s a tolerably round number for a group of insects that are as hard to chase down as odonates. Even though there are only seven families of dragonfly species in both Americas, I still can’t separate many of them in the field even to the family level; it’s only with a camera that I stand a chance. I’m trying to change that, little by little, by learning the species that occur commonly, so that I’ll recognize anything new. (If anyone has a simple flight silhouette technique for sorting out, skimmers and darners at a glance, I’d love to buy it!  The keys in my major reference works are either too complex, like the one in Garrison, Ellenrieder, & Louton, which includes all the genera of North and South America, or, if they’re as straightforward as the one in Mitchell & Lasswell, it still requires that you have the insect in hand.)

Part of my problem, I think, is that most of the species I see are members of the Libellulidae, the skimmer family. Large and diverse as it is, it’s still only one of the seven families; it’s pretty rare that I see other flight silhouettes at all! (Last Saturday at Yamato Scrub I got excited because I saw a silhouette I didn’t recognize; turned out to be some kind of sphecid wasp.) If I don’t often see the other silhouettes, I’ll have a hard time learning them, won’t I? (Guess I’d better get out in the field more often…) As you know, there are, according to Odonata Central, 53 distinct species in Palm Beach County.

Here then, is a typical silhouette of a libelullid, or skimmer, as seen by me in a tree:

This species, Tramea carolina, a member of the skimmer family, is fairly common in my area. Most people call it Carolina Saddlebags, because of the large markings on the hindwing; they really do sort of look like the thing is carrying luggage back there!

However, if you click on that link in the previous paragraph (the #1 Google link for Carolina Saddlebags), you’ll see why I might prefer the more descriptive name given to it in 1989 by Sidney W. Dunkle, in the first ever color photo guide to dragonfly species anywhere in North America: Violet-masked Glider. After all, that #1 linked-to page on the Carolina Saddlebags is to a website describing the dragonflies of New Jersey!

I like that name better for a couple of reasons. One, it avoids the tendency that has fouled up the common names of birds for centuries, that being to name a species based on a location that it might or not occur in, just because that’s where the first specimen was encountered. Two, it’s descriptive.

Whatever name they go by, though, they certainly are distinctive dragonflies; when I see these guys, I know I’m looking at a skimmer, probably a Tramea species, and I even have a good shot of telling whether it’s a Carolina or a Red. It’s a start!


Dunkle, S.W. (1989). Dragonflies of the Florida Peninsula, Bermuda and the Bahamas. Gainesville: Scientific Publishers.

Garrison, R.W., Ellenrieder, N.V., Louton, J.A. (2006). Dragonfly Genera of the New World. Baltimore: Johns Hopkins UP.

Mitchell, F.L. & Lasswell, J.L. (2005). A Dazzle of Dragonflies. Texas A&M UP.