Here in the mid-Atlantic region I sometimes find it difficult to distinguish between Ashy and Lancet Clubtails, especially the females. The Ashy Clubtails here don't darken significantly with age, unlike in other regions. Thus they are the same color as Lancet Clubtails, and the pattern on the abdomen is similar. The Lancet Clubtail is noticeably smaller, but that doesn't always help if you don't see them next to each other. Individuals vary within a size range. If a given dragonfly is too ambiguous, I just throw up my hands and call it a "Lashy" Clubtail!

The male Lancet Clubtail's abdomen has a yellow "lancet" shape extending all the way down segment 8. Segment 9 has a large yellow area. The club is narrow with noticeable yellow where the sides of the club flare out from the abdomen. The Ashy Clubtail by contrast has only a small triangular spot on segment 8, and sometimes lacks the yellow on segment 9. The club is extremely narrow and has only a thin line of yellow on the flared out edges.

The female Lancet Clubtail's abdomen has a yellow "lancet" shape extending all the way down segment 8. (It's a little hard to see in this photo due to glare). There is usually a large yellow area on the top of segment 9. The Ashy Clubtail by contrast has only a tiny triangle on segment 8 or no yellow at all. If yellow is present on segment 9, it is a rather thin line.