Ken I posted this to ask which species of aphid this is. Is it not possible to tell from this photo? Thanks.

I saw that you had posted a number of images, and assumed you were familiar with the process. Many experts never even visit ID Request. Images are moved into the Guide, where they are more likely to be seen and, with luck, identified. The important thing to realize is that the ID process doesn't stop just because an image has been moved. Just hold on a bit. If it's possible to ID your aphid beyond family, Natalie or one of the others experts will do so. :)

Ok, I see, I did not know that! Thanks for explaining. I think in the past most of my images have been IDed in the ID request section so this is a first. Thanks for looking out for me!

Most Aphids are very difficult to identify from images, most aphids are difficult to ID with a slide mounted specimen and a high-powered scope. There are some that have pretty distinct characters and are easier than others, and then there are some where it is impossible.

On lettuce, red with black siphunculi, this is probably Uroleucon.

Thanks Natalie for your helpful response and for teaching me a new word: siphunculi!