Friday, October 18, 2013

Small beginnings: sorting through leaf packs at the Doyles

This isn't one of the "small beginnings," but who can resist starting with this spectacular small minnow mayfly.  Baetis pluto, male, not quite fully mature.   Key diagnostic features: "tergum 5 relatively pale, segments 6 and 7 almost completely dark...middle caudal filament 3/4 to subequal to lateral filaments, usually with distinct dark band on caudal filaments medially."  (Beaty, "The Ephemeroptera of North Carolina," p. 6)

I had good sunlight for this one, so I got some very nice photos -- it's a colorful nymph.


But it was a morning for finding small insects -- those we'll watch develop and grow through the winter and spring.

1. Green stonefly (Chloroperlid), genus Sweltsa.  First of the season.

2. Pronggilled mayfly, genus Paraleptophlebia.  First of the season.

3. Brushlegged mayfly, genus Isonychia.  Not the first of the season, but one of the "palest" Brushlegged nymphs I've ever seen.  Obviously, just recently molted.

4. A "smallish" flatheaded mayfly, Maccaffertium vicarium.  First of the season.  This is one of the few streams in which I've seen this species.

We can pick this one out by noting the dark bands on some of the tergites and all of the sternites.

5. And then there was this small stonefly, the first thing I picked up this morning.

I was fairly certain it was the Perlodid stonefly, Diploperla duplicata.  The colors were right, and we start to see them at this time of year.   But no -- notice the thoracic gills sticking out at the sides.  So, it's a common stonefly, one with anal gills present.

Looks to be a young Eccoptura xanthenses, one on which the distinct yellow pattern at the front of the head is not very clear.

We should start to see small winter stoneflies anytime now.  I wouldn't be surprised to find them next week.  

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