This is a male Clamp-tipped Emerald, named for the distinctive clamp-shaped claspers at the end of his abdomen. Clamp-tipped Emeralds patrol shady forest streams, and sometimes venture into nearby fields or open fens to feed. This male was photographed at Cedar Bog.

This is a female Clamp-tipped Emerald. Clamp-tipped Emeralds have thicker abdomens than the super-thin Mochas. Clamp-tipped Emeralds also have two yellow stripes on the sides of their thorax (Mocha Emeralds are unstriped). Clamp-tipped Emeralds do not have yellow dots along their abdomens like Mochas do. 

Female Clamp-tipped Emeralds have a thorn-like ovipositor. Females often have mud-stained abdomens, from depositing their eggs in muddy surfaces. The individual at left was photographed on October 7, 2017, at Spring Lakes Park in Bellbrook. That was an unusually late date for Ohio. Clamp-tipped Emeralds are more common in July and August. 

Mocha Emeralds are usually found along small creeks in shaded areas. They are probably more common than our records indicate, because Mochas are very difficult to find perched. They perch in shady spots among tree branches, where their dark brown coloration makes them almost impossible to see. I was very lucky to find this teneral female. She fluttered right past my face and stayed perched for a long time. Photographed June 30, 2019, at Siebenthaler Fen. 

This is a female Mocha Emerald. She is a teneral (newly emerged) dragonfly. Mocha Emeralds have long, thin abdomens with small yellow dots. (These dots might be faded in some individuals.) There are no visible stripes on the side of the thorax. 

Close up view of the yellow stripes on the thorax. This Clamp-tipped Emerald was photographed at Siebenthaler Fen on July 3, 2020. (Siebenthaler Fen has both species of emeralds.) 

This female Clamp-tipped Emerald was photographed at Beavercreek Wildlife Area. There is a good population of Clamp-tipped Emeralds at BWA, but it is very difficult to find them perched.