Summary for 2013 and looking ahead to next year

While the year isn't over, it's been a little over three years since I started writing this blog.  So, I thought I would comment on this year's achievements.

A: Statistics.  I continue to find it surprising -- but satisfying -- that there are so many people in so many countries, that share my enthusiasm for this kind of study.   Here are the statistics on that as of this morning.

1. Total number of page views: 106,615
  Top 5 countries
     U.S., 67,293
     Canada, 3829
     U.K., 2928
     Russia, 2371
     France, 1713

2. Number of countries in which people are viewing the blog: 152

3. Months with largest number of page views: October, 2013; 6563: November, 2013: 6139
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B: Main focuses of the blog.  While I continue to try to record the first time each season that I see one of our regular taxa and continue to give "stream reports" on what I'm finding in local streams,  I find myself primarily focussing now on three different things.

1. I want to compile the most complete EPT list that I can for the streams in this part of Virginia.  I have no pretensions that my list will ever be exhaustive, but I'll keep working away on this project as long as my enthusiasm continues and I can still bend over!  The original EPT list was posted on 9/8/12, but I've continued to keep that list up-to-date.

2. I love finding new taxa -- and working out the ID.  It's the most exciting part of this hobby.

3. And I continue to try to get the best photos I possibly can of all of our taxa -- the regular and the new.
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C. Findings this year.  I have to admit that I'm partial to stoneflies -- the Perlodids in particular, especially the genus Isoperla.  And I found three new ones this year.

1. Isoperla davisi: Buck Mt. Creek

2. Isoperla orata:  Rapidan River

3. And Isoperla nr. orata:  Upper Doyles River, Rapidan River, and Buck Mt. Creek

The designation "Isoperla nr. orata" is my own -- nothing official about it.  Still, the resemblance to I. orata is clear, and they have strikingly similar laciniae.

I. orata

 I. nr. orata

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Other new taxa this year (not a complete list):

1. The common stonefly, Paragnetina fumosa (Buck Mt. Creek)

2. Common stonefly, Agnetina flavescens (Rapidan River)

3. Giant stonefly, Pteronarcys dorsata (North Fork of the Rivanna, Buck Mt. Creek, Rivanna -- main stem)

4. Flatheaded mayfly, Epeorus fragilis (South River, Greene County)

5. Small minnow mayfly, Labiobaetis propinquus (Rivanna River at Crofton)

6. Freeliving caddisfly larva, Rhyacophila fenestra/ledra (Doyles River, Lynch River)

7.  And the humpless casemaker just found by my friend in Sugar Hollow, Adicrophleps hitchcocki -- an "imperiled" insect in the state of Virginia

After three years, it's still a whole lot of fun.

Mayfly

Mayflies are not actually flies at all. They are insects in the order Neuroptera and the family Ephemieridae, which translates into "short-lived" and likely eludes to the very short lifespan of these insects.

How do we know if something is a fly or merely called a fly? Here is an easy way to tell the difference, if the name is all one word like Mayfly, Dobsonfly, Caddisfly, Dragonfly, Damselfly, etc.. then it is definitely NOT a fly, but rather belongs to some other order of insect. If the insect has a first and last name like House Fly, Bot Fly, Flesh Fly, Flower Fly, Robber Fly, Bee Fly....etc. Then it definitely IS a fly.

They are one of the most commonly seen insects at porch lights in early summer or sometimes fall.
 The species I see more often than any other is the Burrowing Mayfly. They are also the largest species of mayfly in Missouri, reaching lengths up to 1 1/2 inches. Most mayflies are found in the Eastern United States, with only few species being found out west. It is not uncommon to have dozens of these at porch light in June, or in the case of this youtube video hundreds of thousands swarming a pole. Check out this Mayfly emergence.

The Burrowing Mayfly, also known as the Golden Mayfly, is a beautiful shade of golden-yellow with pale bands across their abdomen (pictured below).As they age their coloring will become darker.

The lifecycle of a mayfly begins underwater as a nymph with seven pairs of gills. They live in the bottom sediment of streams, slow moving rivers, ponds and lakes. The nymphs feed on sediment, diatoms and several species are predatory and feed on other aquatic insects. After numerous molts (skin sheds), they will emerge approximately one year after hatching in the water. The males typically appear first, as subimago adults,meaning they are not completely formed adults yet, they will shed their skin one more time before completing their lifecycle to adulthood. These subimago's are a favorite food of trout and are often used by fisherman as bait. Trout fishermen also use mayflies as a model for the flies that they tie for bait. Mayflies are the only group of insects to have this subimago stage into adulthood. As a subimago they do not fly well, cannot reproduce and lack the coloring of the adult form that would attract a mate. Within 24 hours after emerging they will shed and become full fledged adults capable of breeding. Females emerge shortly after males and also shed their skin for the final time. Mating occurs within hours of emerging.


Time is of the essence, when you only live a day or two, or perhaps only mere minutes (for some species) there is no time to waste on frivolity. Soon after mating, the female will drop her eggs upstream in the water, the current will softly carry the eggs downstream and deposit them on the substrate in the bottom of the stream. If the eggs are laid in lakes or ponds she will drop them wily-nily on top the water, and the eggs sink to the bottom. In some parts of the world the emergence of mayflies is a sight to behold, they all seem to appear at once in a mass exodus. Millions of mayflies rising up out of the water in one large swarm, landing on every available surface may seem like a nuisance to many humans, but these little insects serve a major role in the lifecycle of other species. Mayflies are not only consumed by trout and other fish, but birds, frogs, toads, and other insect eating creatures get in on the all-u-can-eat buffet of mayflies as well.

                                                         (Jumping spider eating mayfly)

I am not sure of the species of this mayfly pictured below on the Sage, but it is a beautiful shade of russet and is much smaller than the Burrowing Mayfly at only 3/4 of an inch in length. 

Although their large numbers can be intimidating, they are completely harmless to humans. They cannot bite, in fact they do not have functioning mouth parts. This lack of mouth parts, also means they do not feed. Their only reason for existence it would appear is to mate, reproduce, and to be sustenance to other creatures. I did find a website that claimed they eat fruits and flowers, but in my opinion this would be fallacy. I know of no mayfly that has the ability to eat, nor do they live long enough to worry about eating even if they could. I would be curious to see what the experts have to say. This is just one example of how much mixed information is out there on the web and it pays to do numerous searches before settling on the truth about something.

The "other" small winter stonefly that we see in at least one of our streams: Paracapnia angulata

No, no -- that's not a small winter stonefly, but it's a nice photo to start off this entry.  The Perlodid stonefly Malirekus hastatus for which see the entry of 1/29/12 (full discussion of the ID).  The backs of the wing pads reveal that this nymph still has a long way to go before becoming mature (it was only 11 mm), but it lacks nothing in color and pattern.  Got some nice photos.

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Now on to the big story.   As you know, almost all of the small winter stoneflies we see in our streams are genus Allocapnia, mostly, I think, A. pygmaea and A. mystica.  They're common at this time of year, with a genus tolerance value of 3.3.  But I had found some "non" Allocapnia Capniids, Paracapnia angulata, in a small headwater stream in Sugar Hollow back in January, 2012.  Today my friend and I went back to that stream, and sure enough we found them again!

Yes I know, they're not much to look at: they were only 5 mm.  But they're real beauties when they mature.  Below, the two that I found on 1/30/12.

Since I just discussed how Paracapnia differ from Allocapnia nymphs (11/22/13), I won't belabor the point.  But the key thing is the shape of the wing pads: "meso- and metathoracic wing pads rounded" (Peckarsky, Freshwater Macroinvertebrates, p. 66).  I.e.

The wing pads are real hard to see on the nymphs that I found since they're so small -- but you can see them in these microscope views.

The "hairy" body -- clearly visible in these microscope photos -- is characteristic of the species (Stewart and Stark, pp. 141-144).  So too, I take it, is the oddly shaped abdomen -- bulbous? -- which swells dramatically from front to back on very young nymphs (see Donald Chandler's photo at http://www.discoverlife.org/mp/20q?search=Paracapnia+angulata).

Very cool.  This is one of the things I was hoping that we'd see today.  It's so nice when you find what you're after.  North carolina, by the way, does not assign a tolerance value to P. angulata.  That means they have not found enough samples.  Beaty does comment however: "Nymphs are collected late fall through mid-winter in the Mountains only," and "Nymphs typically occur in small headwater streams, possibly in leaf packs."  (Beaty, "The Plecoptera of North Carolina," p. 1)  That's where they were: I found them in leaf packs in a small headwater stream in the mountains (elevation, ~1200 FASL).

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We saw a lot of Peltoperlids (Roach-like stoneflies) today and a lot of common stoneflies -- Eccoptura xanthenses -- both of which are common in these small headwater streams.  And we found some flatheaded mayflies, M. merririvulanum and M. pudicum.  But I only photographed two other insects.

1. A Leuctrid -- rolled-winged stonefly -- the first I've seen so far this year, and I saw more than one.  Notice the long, thin abdomen.

2. And a spectacular Ameletid mayfly -- probably Ameletus cryptostimulus, but it's a little too early to call that for sure.

Oh.  I did find an Allocapnia small winter stonefly as well.  So they are found together.  Think this one is A. mystica.