29 July 2005

Bombyliidae: Geron sp.

You know I have a bit of an obsession with bee flies, even ones I haven't seen myself. Here's a cutie I found today. The odonata update is below.

This tiny, hump-backed little bee fly is probably from the genus Geron.

A Spreadwing Update

Yesterday, I spent some time at the University of Michigan Museum of Zoology in the odonata range with the accomodating and helpful Mark O'Brien, researching some of the species that have been recorded in Wayne Co. that I personally have not seen. The big news, I guess, is that Elegant Spreadwing, Lestes inaequalis, is now striken from the list. It's inclusion was based on a lone record, a female specimen taken several years ago. I took a look at it, and lo and behold, it was mislabeled (note, MFO: I could have said "misidentified"). Males are easy to ID, their inferior (lower) claspers are longer than the superior (top) ones. You can kind of see this in the photos here and here, but it's really obvious in the hand, even without magnification. Females ("Lestes without testes" Mark calls them), however, usually require a microscope and some experience. I've looked all over hell's half-acre in the county for this species, but so far no luck.

We also went over some literature records. Several are from prior to 1880 (Hagen's Bluet, Enallagma hageni; Canada Darner, Aeshna canadensis; Mottled Darner, A. clepsydra; and Williamson's Emerald, Somatochlora williamsoni), and others might be in error. Of the 90 species on the checklist, there are only 13 I haven't seen, and half of them are species that either haven't been seen for over 100 years or that I suspect are in error. Eventually, Mark and I became sidetracked into reading some of the correspondence given to the museum by E. B. Williamson (the MOS newsletter's namesake) from colleague Clarence Kennedy. I always find it interesting to get to know historical figures from a personal perspective rather than just seeing their published papers and the results of their field work. Let's just say that these two men were particularly intriguing; Mark promises to liven up our winter months summarizing some of these riveting letters in his blog.

Today I was hoping to find either Elegant Spreadwing or Common/Southern Spreadwing (Lestes disjunctus disjunctus and L. d. australis). There actually aren't that many L. d. disjunctus specimens from southern Michigan; I don't find them all that common. There are just a smattering of L. d. australis specimens from the state.

Now that I have a bike rack, I'm able to explore further afield at the metroparks. There is a 3-mile stretch between Lower Huron and Willow metroparks that, from an aerial view, looked to have a nice old wooded oxbow near the bike path, so that's where I headed. This was nearly all dried up, just squishy much and lots of wetland vegetation. It was loaded with Lestes, mostly Sweetflag Spreadwing, L. forcipatus. Wherever I find these, I find A LOT of them. The males look pretty much like Common Spreadwings. The easiest thing to do is catch a pair and take a look at the female. If her ovipositor is longer than her superior anal appendages, like this, then it's a pair of Sweetflags. I netted every nth pair that I couldn't get a good look at through binoculars, but could not come up with Common/Southern. There were a smattering of Slender Spreadwings, L. rectangularis, some Ruby Meadowhawks, Sympetrum rubicundulum, and the many of the ubiquitous Blue-fronted Dancers, Argia apicalis. Despite the lack of diversity, this looks like a great spot earlier in the season, and later on for patrolling Aeshnas. I'm headed to a different spot furthern downriver tomorrow.

20 July 2005

Skimming Bluet

Getting tired of seeing me post damselfy photos? Well, for me, the bluets are like miniature shards of the deep blue July sky, skittering through the grass at my feet, and symbolic of the summer season I love so much.

Skimming Bluets (Enallagma geminatum) are very dainty, and usually seen dancing over glassy-surfaced ponds. This one paused nearby for me to admire.

14 July 2005

Blue-ringed Dancer

The Blue-ringed Dancer (Argia sedula) is the least common of the blue dancers in our area. Although I noted them along the Rouge River some years ago, I did not encounter them again until yesterday, when I obtained the necessary first voucher specimen to put them officially on the Wayne County list. I think they are the most beautiful of Michigan's Argias; this photo hardly does them justice.

10 July 2005

Great Blue Skimmer: New for Michigan

Great Blue Skimmer (Libellula vibrans) was first recorded in Michigan in 1995, described in a paper published (in Japanese) in the journal Aeschna by Tokihiro Nishida. He had one on 22 June 1995, and photographed a male 10 July 1995, at a small wooded wetland in Westland, Wayne Co. If he obtained a specimen, it is not in the University of Michigan odonata collection.

I think I've looked at this paper, with its tantalizing color photos of species in the county that I have yet to find, dozens of times. In 2004, I went to what I figured HAD to be the swamp Nishida described in Westland, an extremely built-up community. It could only be at Holliday Nature Preserve, a county park. Although I returned again and again, finding other species he noted there, there was no sign of L. vibrans. The swamp also appeared to be filling in with button bush and fallen trees, as seen below.

Accessible wooded ponds are hard to come by in this county. One other looked promising, but repeated visits in 2005 did not turn up this species. Perhaps Nishida's Great Blue Skimmers were just wanderers, and would not be found again without luck, and a year when conditions, perhaps drought in the southeast, brought L. vibrans north to Michigan.

I thought perhaps this might be the lucky year. The Northeast Odes listserv noted an influx of Great Blue Skimmers in New York state. Mark O'Brien reported sightings in Washtenaw Co. just last week. In fact, he told me he was going to go try to voucher one for the first official state record on Saturday. Alas, I was committed to do a survey at Humbug.

We finished our survey of Humbug yesterday (which did not turn up Comet Darner, Painted Skimmer, or any other interesting odonate) sooner than expected, so Stylurus and I decided to head up to Holliday NP. Within five minutes of arrival, I called excitedly over our two-way radios "It's here! I have a male over here!" Just like the books said, this Great Blue Skimmer kept returning to his perch in the dappled sunlight after looping out over the swamp. The very mucky, duckweed-covered-water-0f-indeterminate-depth swamp. Right in front of me. So close and so obstructed by branches I could not possibly get a good swing. I had promised myself if I finally found this thing I'd go in the water after it. Momentarily, I was standing in some very fragrant, warm-as-piss gunk. Stylurus arrived in time to see our bug quite well, before it flew out over the button bushes. We hunted as best we could to no avail.

This brought about a change in today's plans. After doing some other surveying, we arrived at Holliday at about 1:30 PM, wearing rubber boots in 90 degree weather. We went in separate directions, and searched unsuccessfully for half an hour. I sat on a moss and raccoon-crap covered stump, wondering how many dozen Blue Dashers I could stand watching in this reeking place. Suddenly, the radio beeped...Stylurus had two males staked out at the opposite side of the swamp!

One cannot race through this area. The water was opaque and filled with downed trees. I made it half way around and onto "land" before I stepped into a hole and collapsed in the putrid mud. I can't cut to the chase -- that was it -- but suffice to say we had a number of males in a much shallower (albeit no less stinky) spot. We were able to obtain some mediocre photos and a voucher for Michigan's first state record -- 10 years to the day that Nishida had one in the exact same place. Domo arigato, Nishida-san.

Nishida, T. 1999. The odonata collected in the United States of America, mainly in the State of Michigan. Aeshna 36:1-20.

Craves, J. A. 2006. First Michigan specimens of Libellula vibrans Fabricius (Odonata: Libellulidae). Great Lakes Entomologist 39: 91-93.

07 July 2005

Swamp Spreadwing

I spent quite awhile in the field today, but found nothing truly notable. I did see my first Swamp Spreadwings (Lestes vigilax) of the year. I'm not sure why, but I love spreadwings. One of our goals is to find Michigan's first Great Spreadwing (Archilestes grandis). Maybe this will be the year.

06 July 2005

That Stylurus...

...turned out to be Stylurus spiniceps, the Arrow Clubtail, for those of you that have been waiting on the edge of your seats. We were a little surprised, being pretty familiar with this species here along the Huron River. In its extreme tenerality (bloggers are allowed to coin new terms), we did not recognize it.

04 July 2005

Kentucky odes, the end

We spent today in Grant County, KY. We now understand why there aren't a lot of records for this county. It was hard finding publicly accessible permanent water. A couple times we found really lovely rocky streams like this one. We were quite surprised at the lack of odonata in them.

A Macromia was patrolling one, and we staked ourselves at strategic points in the stream. This is where my brilliant new water shoes came in handy. Unfortunately, the river cruiser only made a few passes and eluded us. We think it was either an Illinois (M. illinoiensis) or Allegheny (M. alleghaniensis).

Halloween Pennant

We ended up with only about two dozen species, including this lovely fresh Halloween Pennant (Celithemis eponina). There were very few damselflies -- no spreadwings and only two species of bluets. And the entire weekend we did not see a single green darner. How weird is that?

03 July 2005

Kentucky odes, day 1

Our holiday weekend was a leisurely ride through small towns in Ohio into northern Kentucky, with the goal of recording some species for the KY odonata survey in the very sparsely covered counties near the Ohio River. We made several stops yesterday. In a backwater leading to the Ohio near Augusta, a teneral female gomphid fluttered by. She turned out to be a Flag-tailed Spinyleg (Dromogomphus spoliatus).

Teneral female Flag-tailed Spinyleg (you can see the spines on her thighs). I like the commuter strap-hanger look.

Near Foster, we went to a boat launch where we could walk along the Ohio, dodging every type of garbage known to man from holiday party boats. Please, people. There were a number of medium-sized gomphids with paddle-like clubs. On the plus side, they tended to perch facing away from us, so we could sneak up fairly close. On the minus side, a good photo was hard to take, and it took us forever to catch one because we had to creep over ankle-twisting rocks. They turned out to be Cobra Clubtails (Gomphus vastus).

Uncooperative Cobra Clubtail.

As we were leaving there, a very teneral clubtail, on its maiden flight, caught the light. Without a whole lot of reference materials, we are uncertain what it is. A cursory look at the wing veins led me to think Ophiogomphus (snaketail), but habitat and lack of extensive green on the thorax seems to vote against that. Stylurus thinks it's a Stylurus, and I am leaning to Stylurus notatus, the Elusive Clubtail. The habitat, size, markings (such as they are) look right. If so, it will be the second one we've stumbled across, when many people can never find one; our first was near the Mississippi in Wisconsin.