Thursday, December 6, 2012

ID Challenge #4 Answer

Click image for a larger version.
Ready for the solution to ID Challenge #4? Let’s start at the top as we consider this mystery Pacific Northwest odonate: Is it a dragonfly (Anisoptera) or a damselfly (Zygoptera)? Probably most people can take a glance and immediately recognize it as a dragonfly, but how do we know for sure?

It looks pretty bulky, the “face” looks relatively flat rather than “snouted”, and the head does not seem very elongated from side-to-side (hammer-headed or dumbbell-shaped with the eyes capping each end). These are all indicators of dragonflies, but another more concrete character is the width of the gap between the eyes at the top of the head. On damselflies that gap is greater than the diameter of either eye; on dragonflies, if a gap is present, it is less than the diameter of either eye. Even at this angle we can see that the gap is smaller. Definitely a dragonfly. You can also just make out that the margin of each eye is angular at the narrow point of the gap—something else you won’t see on a damselfly. Here’s a post I did a while back on differentiating dragonflies and damselflies which illustrates the head/eye shape.

Saturday, December 1, 2012

ID Challenge #4


Wow, it’s been a long time since we’ve had an ID Challenge! Here’s a close-up of some mystery odonate which is found in the Pacific Northwest (or parts there of). Where else does it occur? I’m not saying. If you’re familiar with the species, it ought to be pretty easy. If you’re not familiar with it, it’ll take a bit of research.

Leave a comment to let me know what you think it is. Comment moderation will be turned on until I post the answer, so they will not be visible in the mean time.

Have fun!


Postscript, 6 December 2012

This challenge is now closed. The answer with a complete discussion is here.


Wednesday, November 21, 2012

Season's Feastings, the Odonate Way


It’s Thanksgiving time in the US, and I’ve been wondering how I could possibly tie a post about dragonflies and damselflies to the holiday. It’s far too chilly and sunless around here to show any odonates enjoying the season. The best I could come up with was a bunch of photos of dragonflies and damselflies eating to their hearts’ content. That is, after all, how many Thanksgiving celebrants observe the day.

Monday, November 19, 2012

High Speed Video of Flying Dragonflies

I recently became reacquainted with this interesting National Science Foundation video on YouTube, and I thought it was worth sharing. Titled Science Nation - Dragonflies: The Flying Aces of the Insect World, it features a species of the eastern United States, Spangled Skimmer (Libellula cyanea), in high speed video clips as it flies and catches prey. At least three other species, and I think a fourth, make cameo appearances in the video as well. Can you spot them all?

If you haven’t seen it already, it’s worth a look. If you have seen it before, it’s worth another look (the video is only two and a half minutes). There is something very calming—almost mesmerizing—about flying dragonflies captured on high speed video.

Thursday, November 15, 2012

The Broken Wheel (When Dragonfly Sex Goes Wrong)


I recently devoted a post to the Olive Clubtail, Stylurus olivaceus, but here’s another photo of the species you might find interesting.

Friday, November 9, 2012

The Foot High Club

 
A few years ago this coupling couple of Carmine Skimmers (Orthemis discolor) were flying low over a ditch in Cahuita, Costa Rica. Odonates frequently fly while copulating—they do it all the time, actually—but this was the only instance that I managed to photograph (and end up with something other than an unidentifiable blur). In case you were wondering, the Carmine Skimmer is not a species any reasonable odonatist can expect to see in the Pacific Northwest. Not yet...

Sunday, November 4, 2012

Olive Clubtail (Stylurus olivaceus): The Lower Columbia's Gomphid


 
Pacific Northwest members of the dragonfly family Gomphidae—the clubtails, are mostly species of the height of the summer season. Even though daylight hours are waning after the summer solstice, daytime temperatures continue to rise and sunny, dry days are increasingly expected. During this time most gomphids are out in force and doing what gomphids do. One species, however—the Olive Clubtail, Stylurus olivaceus—is just starting to emerge while other gomphids are at the zenith of their adult activity.

Tuesday, May 29, 2012

South Carolina Highlights, Part 3





This is the third and final installment of a short series of posts about my travels in South Carolina while attending the annual meeting of the Dragonfly Society of the Americas in May 2012. Check out Part 1 and Part 2 if you haven’t seen them yet.

The third leg of my travels in South Carolina was the post-meeting trip of the 2012 annual meeting of the Dragonfly Society of the Americas. We left Florence on the morning of 6 May and made our way toward the northwestern tip of South Carolina and adjacent Georgia, and on the way we took a break to check out Ramsey Creek in Oconee County to see what was flying. There was not a lot to see, but there were a few Gray Petaltails (Tachopteryx thoreyi) which are always fun.

Thursday, May 24, 2012

South Carolina Highlights, Part 2



This is the second installment of a short series of posts about my recent travels in South Carolina while attending the annual meeting of the Dragonfly Society of the Americas in May 2012. Check out Part 1 if you haven’t seen it yet.

The second phase of my time in South Carolina was the 2012 annual meeting of the Dragonfly Society of the Americas (the first phase was the pre-meeting trip). We stayed in Florence for the variety of lodging and food options while the field time and business meeting were to the north in the sand hills area around Cheraw. In this post I’ll share some odonatalogical highlights from the field on 4 May 2012 which, in the case of myself and my travel companions, was spent entirely at Campbell Lake—a beautiful body of water ringed with lilypads and studded with towering cypresses (see photo above).
 

Saturday, May 19, 2012

South Carolina Highlights, Part 1



 
I’ve done some traveling lately, first to Louisiana (which I have written about in a few recent posts) then to South Carolina to attend this year’s annual meeting of the Dragonfly Society of the Americas. The meeting was held in Florence, but there was a pre-meeting trip to Conway in the coastal plain, and a post-meeting trip to the wild and scenic Chattooga River and surrounding hills at the far western end of South Carolina and neighboring Georgia. In this post I’ll share what I photographed during the pre-meeting trip in the Conway area. My time here was spent entirely on the Little Pee Dee River—a beautiful blackwater stream enveloped by lush forests and cypress swamps.

Saturday, May 12, 2012

My first northwest odonates of 2012

...and I specify “northwest” because I had been traveling in Louisiana and South Carolina the last few weeks and I saw lots of odonates during that time. See my previous three posts for a taste of what I saw in Louisiana; I’ll try to put something together on the highlights in South Carolina during the Dragonfly Society of the Americas annual meeting there.

Yesterday—my first full day back in Vancouver, Washington, after returning from South Carolina, I visited some ponds in the Burnt Bridge Creek Greenway. I only started visiting these ponds a couple months ago, so it’ll be interesting to see what the odonate fauna is like as the season progresses.

Monday, April 30, 2012

Lake Martin, Louisiana, Revisited

 
I leave Louisiana tomorrow morning to make my way to the Dragonfly Society of the Americas annual meeting in South Carolina, but I was able to make another visit to Lake Martin a short distance outside of Lafayette. I found a few things in addition to what I saw during my last visit (see previous post) and I’ll just show those briefly since I still need to get packed tonight!

Saturday, April 28, 2012

Lake Martin, Louisiana

 
A couple days ago I spent a little bit of dragonflying time at Lake Martin which is just a short drive from Lafayette, Louisiana. It’s a lush, beautiful lake with lots of Spanish moss-enshrouded cypress trees emerging from the lake waters (did you know that Spanish moss is actually a bromeliad?) and, of course, the occasional alligator playing “I see you, but you don’t see me.”

The conditions were not great since it was very blustery and the odonates were not too interested in posing for photographs. The diversity of species wasn’t too impressive either—not very different from what I saw at Avery Island a few days prior (see previous post), but I do have a few photos worth sharing.

Thursday, April 26, 2012

My first flying odonates of the year (in Louisiana)

It’s been a while since I have posted anything, but I’m on the road—currently in Louisiana, then in South Carolina next week for the Dragonfly Society of the Americas annual meeting, so I thought I’d share a few photos while traveling.

I had not yet seen any adult odonates at home in the Pacific Northwest, so my first of the year were at Avery Island, Louisiana—a salt dome protruding out of the marshlands and bayous where the world supply of Tabasco hot sauce is produced. Also located here is the Jungle Gardens, a botanical garden and bird sanctuary established by the McIlhenny family with plenty of alligator-occupied ponds and odonates. The odonate diversity was not great, but some are species that do not occur in the Northwest. Below are several species photographed at the Jungle Gardens a couple days ago.

Sunday, March 25, 2012

My new odonate nymph digger

For a couple of years I’ve been using a modified tennis racket as one of my implements of aquatic life exploration. I cut the strings out and replaced them with a piece of window screening. I scoop up sediment and strain it, or sweep through submerged vegetation, or catch what is dislodged from rocks and debris in streams. It has always worked really well, but it’s a bit big and heavy to carry around along with my aerial net and camera. I thought I’d try something a little smaller and lighter.

Monday, March 12, 2012

They are Dragonflies, not Dragon Flies

Once in a while I’ll see someone refer to “dragon flies” or a “dragon fly” which causes a brief piercing sensation in my head. Just kidding—it’s more of an open-handed thump to the back of the skull. Just kidding again! It really isn’t a big deal, but I thought I would explain the protocol regarding whether the fly part of the name is separate or not.

Monday, March 5, 2012

Migrant Meadowhawk Research Takes Wing


 
Last fall I wrote in It’s Time to Watch for Migrant Meadowhawks about migratory Variegated Meadowhawks (Sympetrum corruptum) which are sometimes observed in the Pacific Northwest flying south in large numbers. Those fall flights are most often observed on the coast—presumably because they are concentrated there during periods of persistent east winds, but large numbers have been observed elsewhere too.

Thursday, March 1, 2012

The Northwest Forktails (Ischnura)




With spring knocking at my door (well, maybe pulling up the driveway if not quite yet knocking at my door), I thought I’d do a little summary of the Pacific Northwest’s forktails (Ischnura). Most of our species appear relatively early in the year, so this is a good time to review them and make sure you’re familiar with the species around here.

Monday, February 20, 2012

Seeing Red: Cardinal Meadowhawk




Most meadowhawks (Sympetrum) are red—at least the males are, and sometimes the females too—but the Cardinal Meadowhawk (S. illotum) is about as red as they get. Mature males are simply vivid. Among the first spring-flying dragonflies in the Pacific Northwest lowlands west of the Cascades, it’s a welcome splash of color after a damp, dreary winter. Look for them at marshes and well-vegetated ponds and lakes of all sizes. Check out this map at OdonataCentral and see if this species has been recorded in your area.

Friday, February 17, 2012

A Checklist of North American Odonata, 2012

Click image to open the PDF.
Just a quick message to let you know that the 2012 edition of A Checklist of North American Odonata by Dennis Paulson and Sidney Dunkle is now available. You can find the PDF (just over 1 MB) here at OdonataCentral.org. You can also just click on the image at right to open it.

Originally published by the Slater Museum of Natural History, University of Puget Sound, in 1999, this document isn’t simply a list since it contains a wealth of information on each species recorded from the continental United States and Canada. In each species entry you can find reference information for the original description, the type locality, etymology of the scientific and English names, and a brief description of its range. Similar information is also presented for each genus.

A sample from A Checklist of North American Odonata, 2012 edition.
 
The introduction has information on the number of species and genera in each family and suborder, the number of newly described species by family and by decade, and on the adoption of standardized English names. At the other end of the document, the extensive annotated bibliography indicates which genera and species were described in each publication, and the appendix wraps it up with a list of synonyms.

If you’re serious (even just mildly serious) about Odonata in North America, this document is a must-have, and since it’s free, you can’t argue about the price!

Monday, January 30, 2012

The Rest of the Story




A picture is worth a thousand words, as the saying goes, but that doesn’t mean that there aren’t many more words lurking behind the photo which tell a much more interesting story.

Sunday, January 22, 2012

Mite-y Dragons: Odonata and Water Mites

If you look at odonates often enough, closely enough, you’re bound to notice some that are accessorized with tiny orbs—often orangish or reddish in color, clinging to various parts of the body like jewelry. But it isn’t “bling” or the latest fad in body art. When I first started catching odonates and looking at them in-hand, I thought they might be eggs which got stuck to the body, but that isn’t right either. What are these sanguine spheroids, these rusty rondures, these blushing bulbous globules?

Male Tule Bluet (Enallagma carunculatum) with a string of mites under the abdomen.
 

Sunday, January 15, 2012

Protoneura: Sparks in the Dark




Considering that it’s January and that I can’t reasonably expect to see an adult odonate for a couple of months in the damp, chilly Pacific Northwest, I thought I’d take you back to Ecuador to profile one my my favorite genera of damselflies.

The Protoneura (21 known species) are small, but relatively long, skinny damselflies in the family Protoneuridae—the “threadtails” as they are known commonly. This is a mostly tropical family found circumequatorially, but three species make it as far north as southern Texas. Male Protoneura are often brightly colored, at least on the thorax, but they also stick to shady areas along forested streams where they can be difficult to spot. It’s not unusual to notice a bit of bright color suspended over a small stream, then realize that it’s part of a Protoneura hovering motionlessly.