Nannothemis and I attended the PIF (Partners in Flight) conference in McAllen, TX in mid-February. Of course, we scheduled a couple free days since the lower Rio Grande valley is a great place to search for insects and birds. There are many great locations to explore in the vicinity. During our short trip we visited Santa Ana NWR, Quinta Mazatlan World Birding Center, Bentsen-Rio Grande Valley State Park, the NABA Butterfly Park, Estero Llano Grande State Park, Old Hidalgo Pumphouse World Birding Center, Laguna Atascosa NWR, and the Sabal Palm Audubon Center.

Dragonfly variety is mid-February is limited, but we did find several species including Citrine Forktail (Ischnura hastata), Common Green Darner (Anax junius), Great Pondhawk (Erythemis vesiculosa), Band-winged Dragonlet (Erythrodiplax umbrata), and Roseate Skimmer (Orthemis ferruginea).

Band-winged Dragonlet, Santa Ana NWR (a more typical place than Michigan!)

Great Pondhawk, Santa Ana NWR

We did even better with butterflies. We found some rarities and some cool-looking species.

Double-dotted Skipper, Sabal Palm

Sickle-winged Skipper, Sabal Palm

It was good to get a little sun and see some bugs again!

Panama Odonata - dry season version

Stylurus and I were in Panama again for 10 days. Here is a little gallery of the species we photographed.

Originally posted 19 January.
Updated with expert input from Dennis Paulson 20 January.
More info on the gomphid on 21 January.
John Abbott weighed in on 22 January.
Another adjustment to the gomphid on 29 January.
4 February: Nick Donnelly offers an opinion on the gomphid.

Additional comments welcome! Captions follow photos.

The two photos above are not the best or of the neatest-looking damselflies, but are probably our most interesting. They are of Anisagrion kennedyi, taken along the Rio Chevo at Finca Hartmann, Palo Verde section, Santa Clara, Panama (12 Jan 2008 by me, top; and 11 Jan 2008 by Stylurus, bottom). According to Dennis, who identified this for us, these are likely the first photos of this species.

Hetaerina cruentata along the Rio Chevo at Finca Hartmann, Palo Verde section, Santa Clara, Panama. 11 Jan 2008.

Camera in right hand, I was able to slowly sneak up on this rubyspot and grab it by the wings with my left hand (proud moment). That enabled me to take a close-up of the distinctive metallic green spot on the thorax that is characteristic of this species.

This rubyspot is Hetaerina miniata. I keyed out the females to reach the identification. Pipeline Road, Gamboa, Panama.

Flame-tailed Pondhawk, Erythemis peruviana. Pipeline Road, Gamboa, Panama. 8 Jan 2008.

Cardinal Meadowhawk, Sympetrum illotum. Finca Hartmann Ojo de Agua section, Santa Clara, Chiriqui, Panama. Too much glare off the water behind it. 12 Jan 2008.

Orthemis levis. Pond at Metropolitan Nature Park, Panama City, Panama. 6 Jun 2008.

Pallid Amberwing, Perithemis mooma. Pond at Metropolitan Nature Park, Panama City, Panama. Many female amberwings of most species have highly patterened wings. This one was quite plain. Amberwings stay coupled very briefly. In the thousands of amberwings I've seen, most have been single males. 6 Jan 2008.

Enough of the red and orange theme.

Pin-tailed Pondhawk, Erythemis plebeja. Pipeline Road, Panama. 8 Jan 2008.

Mature female Black Pondhawk, Erythemis attala. Pipeline Road, Gamboa, Panama. 7 January 2008.

Not-so-mature female Black Pondhawk, Erythemis attala. Pipeline Road, Gamboa, Panama. 7 Jan 2008.

Mangrove Darner, Coryphaeschna viriditas. Pipeline Road, Gamboa, Panama. 6 Jan 2008.

You know from my previous trip how much I like helicopter damselflies. We saw only one of the big Megaloprepus caerulatus, but saw quite a few of this species, Mecistogaster linearis, nearly all females. This one was preoccupied eating, and I was able to catch her to photograph her. She resumed her meal when we let her go! Pipeline Road, Gamboa, Panama. 7 Jan 2008.

Evening Skimmer, Tholymis citrina. A crepuscular species, tough to photograph in the shade. Pipeline Road, Gamboa, Panama. 7 Jan 2008.


Dennis thinks this is Argia medullaris, common in Costa Rica. He said if he had to name it, he'd call it the "Electric-blue Dancer." My guide to Central American odes did not have this species listed in Panama. Finca Hartmann, Ojo de Agua section, Santa Clara, Panama. 12 Jan 2008.

I thought this might be Spine-tipped Dancer, Argia extranea. Dennis said I was correct, although the taxonomy of this species groups isn't all worked out, so it might be a closely related species. Finca Hartmann, Ojo de Agua, Santa Clara, Panama. 12 Jan 2008.

Protoneura amatoria. Over a deeper pool in the first stream crossing (Juan Grande) on Pipeline Road, Gamboa, 8 Jan 2008.

Red-faced Dragonlet, Erythrodiplax fusca. Pipeline Road, Gamboa, Panama. 8 Jan 2008.

Striped Firetail, Telebasis filiola. Pipeline Road, Gamboa, Panama. Face here and huge here. 8 Jan 2008.


Argia indicatrix. Metropolitan Nature Park, Panama City, Panama. 15 Jan 2008.

Blue-fronted Setwing, Dythemis multipunctata. Immature male. Pipeline Road, Gamboa, Panama. ID's by Dennis Paulson. 8 Jan 2008.

Another dasher, a female Micrathyria laevigata. Another look here, and a male from our last trip here. Pipeline Road, Gamboa, Panama. 8 Jan 2008.

Rhodopygia cardinalis, based on the basal spot on the hind wing, and wing veination of a fresher individual. Pipeline Road, Gamboa, Panama. 7 Jan 2008.

---

The mystery gomphid.

This was really cool, as there are not many tropical gomphids. I flushed this gomphid at the Juan Grande crossing on Pipeline Road, Gamboa, Panama (first stream, 2 km from gate) on 8 Jan 2008. Stylurus was able to catch it (we ended up catching several more odes by stealth and quick hands), so we got additional photos, including the face and claspers and wing veination.

I originally thought this might be Phyllocycla volsella. However, it is too large for this genus. Dennis Paulson had this to say:

"It's in the Aphylla-Phyllocycla-Phyllogomphoides group, but I'm not even sure of the genus. Gomphids are still the group of anisopterans that are most poorly known throughout much of the tropics, as many species fly only briefly during the rainy season. There are fewer species in the dry season, and they are often in that group."

Nick Donnelly, however, also thought this looked like P. volsella, and his estimate of the size of volsella is a bit bigger than Paulson's. I'm leaning in this direction again.

I found amongst my literature a key to the Odonata of Barro Colorado Island in the Panama Canal, in Spanish [1]. Here are the gomphids listed for BCI, which is not too far from Pipeline Road.

Epigomphus quadracies. This genus has 2-3 cubito-anal crossveins on the wing. Our individual has only one.

Phyllocycla volsella. The BCI keys notes this as occurring in June and July, but that it is abundant along the Rio Frijoles (which is on the mainland near Pipeline Road) during the first months of winter.

Phyllogomphoides appendiculatus. According to my original key [2], the thoracic pattern of this species would not be as completely and strongly striped, and the inferior appendages should be easily visible in the dorsal view, which they are not. The BCI key says it is yellow and black (not green) and is found in late summer and early winter. It also mentions an undescribed Phyllogomphoides species that comes out in June and July with wide yellowish or greenish stripes on the top of the thorax.

Aphylla obscura. This is an interesting possibility to me, although my original key [2] indicates the flanges on segment 8 should be smaller and the "anterior half of dorsum of abdominal segment 7 not pale, but the same color as the posterior half." It is pale on ours. The thoracic pattern looks good, though. The BCI key [1] notes that this is a large species that emerges in the forest as early as February or March, that the thorax is well marked with black and green, and that the extreme tip of the abdomen is reddish (I also tracked down a description by Fred Sibley that notes this coloration). Ours does have warm tones on the tip of the abdomen, although I'm not so sure I'd say it's reddish. Donnelly agrees our bug is not this species.

Just more food for thought, and an attempt to keep all my info in one place!

This is one I forgot to add to the first post, and it remains unidentified. Plantation Road, near Gamboa, Panama. 7 January 2008.

---

These are apparently not identifiable via photos.

Unidentified Argia which is not, as I thought it might be, A. pulla or frequentula. Shot of the claspers and another shot by Stylurus here. Along the Rio Chevo at Finca Hartmann, Palo Verde section, Santa Clara, Panama. 11 Jan 2008.

I'm not sure these are the same species. We saw quite a few females, mostly at the Metropolitan Nature Park in Panama City (first photo 6 Jan 2008). The bottom photo was from Pipeline Road, Gamboa, 7 Jan 2008.

This is similar to the first unidentified one, but it has more black on the thorax. Metropolitan Nature Park, Panama City, Panama. 15 Jan 2008.

---

[1] Lista Preliminar de Nombre y Clave para Identificar los Odonata (Caballitos) de la Isla de Barro Colorado. Michael May, translated by C. L. Castro. Smithsonian Tropical Research Institute, 1979.

[2] The Dragonflies of Central America, exclusive of Mexico and the West Indies. A Guide to their Identification, 2nd Ed. Steffen Forster. Gunnar Rehfeldt, 2001.

First state record: Band-winged Dragonlet

There is something unsettling about doing field work with the sun obviously autumnal -- low in the sky -- fallen leaves underfoot...and sweating in 86F temperatures and high humidity. In spite of the the fact that the calendar page flipped days ago to October, we couldn't pass up heading out to do one last survey at the Detroit River International Wildlife Refuge Humbug Marsh Unit. The USFWS will certainly be getting its money's worth out of this grant.

Last year, we were on the lookout for some rare vagrants that had showed up in Ohio. One of them was Band-winged Dragonlet (Erythrodiplax umbrata), a species most common in the U.S. in Texas and south Florida. Here's the distribution dot map from Donnelly's project [1].

So this species is known to wander, although Ohio seemed quite far-flung. And once again this year, Band-winged Dragonlets were found in Ohio, this time in the northeastern part of the state in Lake and Geauga counties. Band-winged Dragonlets are found in temporary ponds and marshes, and the Ohio subjects were found in shallow scrapes with only a little water.

This thought was in our minds as we entered the Refuge. The front third of the large brownfield portion is undergoing restoration, and had been scraped clean in the spring. Now, it is mostly uneven sandy soil with sparse weedy vegetation. It rained several days ago, and there were perhaps a half dozen depressions with a few inches of water in them.

Stylurus was ahead of me, and passed by the first glorified puddle. As I approached it, I saw a patrolling dragonfly that had black on its wings. I automatically called out "Twelve-spotted Skimmer," as this would be a late fall date for that species. Almost as soon as I said it, I noticed this ode was smaller than a skimmer, had a dark blue body, and not enough "spots." Stylurus was heading back my way. "This could be a dragonlet!" I called out. He got closer and took a look, and agreed. North America's northernmost record of this species!

This wet spot was only a few yards square, but the dragonlet rarely landed. It seemed reluctant to leave, but flew around busily. It perched briefly several times, but would take to the air as soon as we moved. Both of us managed to fire off a few photos -- Stylurus with a point-and-shoot, and me with my good camera, but a macro lens.

Suddenly, another male dragonlet flew to the puddle. They circled each other, and flew to the treetops. It was only moments before one returned. Not wanting to chase it off for good, we quickly explored the other nearby puddles. There was a dragonlet at the closest one. Perhaps 15 minutes passed without us being able to get a good swing at either one. With Stylurus near one puddle, I went back to the first. Both dragonlets appeared, and while they were preoccupied with each other, I was able to scoop both of them up. The first and second Michigan records in one net swing.

We found very little the rest of the day. Some Familiar and Tule bluets, Common Green Darners, Wandering Gliders, a couple of Black Saddlebags, some Eastern Forktails, and a handful of Aeshnas, probably Shadow Darners. Band-winged Dragonlet was the 35th species we have recorded at the Refuge under our survey grant this year. It also represents the fifth state record for the Urban Dragon Hunters, and something like the 45th county record, bringing the Wayne County total to 94 species. It was a fine way to end the field season.

But stay tuned. I'll try to do an annual summary, and we will be doing some traveling in the tropics long before the 2008 Michigan season begins again. More to come!


[1] Donnelly, T. W. 2004. Distribution of North American Odonata Part II: Macromiidae, Corduliidae, and Libellulidae. Bulletin of American Odonatology 8:1-32.

Taking to the water

Part of a grant I received to do baseline odonata survey on USFWS land included larval sampling. It's still a little early in the fall (we discovered) to get a lot of semi-mature (and therefore identifiable to those of us who specialize in adults) larvae. But we decided to spend a glorious autumn day seeing how it would go.

We sampled several areas. One was a portion of the Detroit River. Stylurus is a champ: he waded right in. That's the north end of Humbug Island in the background, and Grosse Ille in the far left background. This is near the southern end of the river. The substrate here is alternately sandy and silty, with the remains of wooden planking installed by a private hunt club decades ago still sunken in the muck in a few places. That's (mostly) duckweed on the river, not algae.

A main objective was to see what is able to breed in an Army Corp of Engineers ditch, created to shunt an old creek, currently nearly entirely underground in a sewer pipe, to the Detroit River. Although mucky and peppered with trash, this little shallow creek has small fish, several kinds of gastropods, freshwater scuds, water boatmen, many aquatic beetles, and some odonate larvae. Aside from a variety of damselfly larvae, we got about a dozen larger specimens of darners and skimmers. Still, not as many or as diverse as we would have hoped. However, this creek is slated for restoration, hence our baseline survey. Here, a friend we enlisted to slog through the mud checks out his haul.

I stayed relatively dry, sorting through the trays of gungus that the men brought me. Note to self: bring a folding table and chair next time. Kneeling on the ground hunched over the trays was bullshit. At least I remembered my reading glasses.

Once finished, we couldn't resist tromping around one of the areas where we typically do transects counting adults. We both saw a nice gomphid -- Arrow Clubtail, Stylurus spiniceps or Elusive Clubtail, S. notatus -- but were unable to net it to confirm its identity. There were a lot of Wandering Gliders (Pantala flavescens), some Common Green Darners, Anax junius and Black Saddlebags, Tramea lacerata, a few Common/Eastern Pondhawks, Erythemis simplicollis, and lots of bluets, mostly Familiar (Enallagma civile) or Tule (E. carunculatum) with a few Orange (E. signatum). And the typical Aeshnas for the date and place: A. umbrosa, Shadow Darner, and A. constricta, Lance-tipped Darner.

The next installment might just be about what we found, once we key out our three dozen or so specimens.

Nearly two years ago, Nannothemis and I found the first state record of Great Spreadwing (Archilestes grandis) for Michigan in northwestern Wayne County. Last year I was delinquent in checking the location in late summer/early fall. One reason for not visiting was my fear of seeing the area around the stream fully developed with office buildings and restaurants and the watercourse being destroyed by trash and runoff. As is too common in southeast Michigan, land is being gobbled up and developed for office parks, restaurants, and shopping areas. This photo from Google Maps shows the vacant land; the creek is visible snaking through the property.


The area is now completely built out; here is the site plan:

On 29 August, while running an errand during lunchtime, I decided to check the stream and development "progress". I was surprised at the amount of vegetation left intact along portions of the stream. Also, there wasn't a large amount of trash or debris in the stream, which was encouraging.
Immediately I found a male Great Spreadwing and subsequently found 2 other males and a female along ~100m of the stream. I only had 10 minutes to check the area and I would guess there were more individuals present. This is a record early date for Michigan by nearly one month.

Andromorphic female Eastern Forktail

I found something cool when Stylurus and I were doing our weekly Odonata census at the Detroit River International Wildlife Refuge Humbug Marsh Unit. Although the final report will only classify relative abundance of each species into one of five simple classes, I have tried to actually count all the individuals we encounter on our transects and plots. This isn't too hard for most dragonflies, but quickly becomes tedious for damselflies. Obviously, it isn't possible or necessary to count every single one, but I tally what I see as I walk slowly along, and have to net a lot of bluets and forktails to make sure I'm getting the right ratio of similar species.

The other day a slightly odd forktail caught my eye. It resembled a male Eastern Forktail (Ischnura verticalis) with a bright green thorax and mostly black abdomen, but the tip of the abdomen had a very reduced blue pattern different from any species of forktail that I could recall. Netting it, I was surprised to see it was a female. I put it in an envelope to examine later.

At home I gave it a close look. It had a vulvar spine [1] and what I could "read" of the prothorax and mesostigmal plates [2] under my microscope indicated it was an Eastern Forktail. However,we'd never seen an illustration of one so strongly male-like and the bright blue pattern on the dorsal abdomen tip was unlike any we'd seen -- on any forktail.

Many species of damselfly have a female morph that is colored like a male. They are not only the minority morph in populations, but also very rarely seen. First, once they get older and more pruinose, they look just like typical females. And of course, not too many people look at enough inch-long insanely abundant insects in the grass to pick them out.

I solicited comments on my photos. Both Nick Donnelly and Dennis Paulson confirmed that this was a rare andromorphic female Eastern Forktail (Dennis has seen only one in his long career). In fact, the incidence of andromorphs in this species is under 1%. Here are the photos; all are clickable for larger sizes. More background follows.

It has been proposed that male-like morphs in female Odonata serve to protect females from being harassed by males. This theory was supported by the fact that female polymorphism occurs more often in species where males search for mates, versus families in which males are territorial (whereby females can avoid harassment by avoidance). The situation is actually somewhat more complicated than that -- beyond the scope of this post. A paper reviewing female andromorphs, various explanations, and evolutionary history is listed and linked to below. It cites a study (done in Michigan, coincidentally) giving the frequency of andromorphs in Eastern Forktails as 2% of 553 individuals and 0 out of 386 others. My specimen will be housed at the University of Michigan's Museum of Zoology Insect Collection.

As an aside, Russet-tipped Clubtails (Stylurus plagiatus) are increasing in number at the same site. A few very teneral individuals were found, along with a number of older ones, and a pair in tandem. Here's a cooperative male:

The evolution and frequency of female color morphs in Holarctic Odonata: why are male-like females typically the minority? (PDF). Ola M. Fincke, Reinhard Jödicke, Dennis R. Paulson and Thomas D. Schultz. 2005. International Journal of Odonatology: 183-212.

[1] Vulvar spine = point on the underside of the 8th abdominal segment in some damselflies; Eastern Forktails have one, Fragile Forktails (I. posita, the other common forktail in my area) do not.

[2] Prothorax and mesostigmal plates = structures behind the head of female Odonata that enable the male claspers to fit and lock on when the pair are in a mating wheel.

Best population of Great Blue Skimmers

Yesterday, I was doing some bird work in an undersurveyed area in Riverview, a downriver community of Wayne Co. Young Patriot's Park is a place I'd been a couple of times -- ball fields, a playground, library, basketball courts, and a woodlot at the northern end. The name stems from the period (1956-1962) when the site was a Nike missile base.

There is a decorative mowed-to-the-edge pond out front, and lots of skimmers and Pantalas flying around the open areas. I'd walked the edge of the woodlot for birds before, as well as some of the trails in it. Yesterday, I started at the north end, and soon discovered that there is a "creek" -- really a straight, shallow ditch -- running through the north end of the forested area. It's been extremely dry here, and the ditch was either dry, damp, or with perhaps three or four inches of water at its deepest. Kids had built a bridge across it where it crossed the trail, but there was plenty of naturally-fallen saplings as well as the usual discarded objects ubiquitous in urban waterways. Personally, I hopped across on a soggy car seat.

It wasn't too hard to walk close to the edge most of the way, as the woodlot clearly flooded in spring, especially on the north side of the ditch, so there wasn't as much undergrowth. The first thing I saw was a male Great Blue Skimmer lazily gliding after a conspecific, then perching in the dappled sunlight on a broken shrub arched across the water. If there is one thing about this species, it is certainly predictable in its habits.

Every few yards, in sunny spots, there was another one or two males. Standing in a patch of grape vines along the banks, two kept mixing it up and landing at my feet. Of course, I did not have my good camera, only a point-and-shoot. The fact that I finally got this nice shot (the best of any so far) and several others is an indication of how unwary and close they were. I didn't have a net either, but did try to swat one with my bird checklist.

They are not that unwary.

At one point I looked ahead, and saw a female skimmer ovipositing in the ditch with the same forward-flicking abdomen dip that I associate with Orthemis. She was very dull and in the shade, but when she finished and went up to a sunny leaf to perch, I saw it was a female Great Blue. The ditch only ran a couple of hundred yards, and without too much effort I was able to count around 15 males and at least 4 ovipositing females. These are the first females seen in the county, and the first positive evidence of a breeding population in the state.

Recap:

• We take the first voucher specimen for Michigan in Westland, Wayne Co., on 10 July 2005, ten years to the day after one was photographed at the same location. I just published a paper on this in the journal Great Lakes Entomologist.
  
• On 28 August 2005, we found several males in a wooded wetland adjacent to the Huron River at Willow Metropark, Wayne Co.
  
• On 16 June of this year, we found a male at a wooded wetland in Canton, Wayne Co. It was still there a week later, but no others were found and we haven't been back again.

This was just an odd and unlikely location, but it clearly floods a lot in spring, and probably stays fairly wet in less-parched summers. It will be worth a few return trips.