Vermont rivers/River sites/French Hill Brook.htm
|State or Province:||Vermont|
|School:||Made Up School|
These are common macroinvertebrates identified from samples from French Hill Brook, Johnson, Vermont.
Capnia stoneflies have hind wing pads that are are broad as they are long. An important distinction of the Capniidae family is the membranous pleural folds that run down the posterior abdomen segments 1-9. These look like two lines running parallel down the back of the abdomen.
Capnia are distinguished by femurs and tibia of forelegs with less than 20 fine hairs and no dorsal femoral fringe hairs.
Capniidae stoneflies have hind wing pads that are are broad as they are long. An important distinction of the Capniidae family is the membranous pleural folds that run down the posterior abdomen segments 1-9. These look like two lines running parallel down the back of the abdomen.
There are about 15 cercal (or "tail") segments on Nemocapnia stoneflies. There are multiple long, fine hairs on these segments, forming a "vertical fringe," which are absent on the basal 5 or 6 segments (closest to the abdomen).
Chimarra are distinguished from the other Philopotamidae by a prominent asymmetrical notch in the frontoclypeus as well as a prominent process on the femora which bears a single hair (seta).
Heptagenia are easily characterized by their flat head. The claws have just one basal tooth and no denticles (serrated edges). The gill on abdominal segment 7 has multiple fibrils at is base (thread-like structures) and has a single tooth on its claws but is smooth otherwise. Gills on segment 7 are similar to those on all other segments, but may be smaller in size.
This mayfly has three "tails" and a unique head shape. Its gills are oval shaped and insert dorsally. More mature nymphs have long, dark wing pads. SMC