Eulachnus Del Guercio
This is one of the conifer-feeding aphid groups that I am not expert in, but somehow enjoy collecting. Eulachnus aphids feed on the needles of pines. These aphids were among the first I collected when in college working at the Oregon State University Hermiston Research and Extension Center in about1988. At the time I was still learning even how to recognize insects like this as aphids.
Eulachnus rileyi (Williams)
As far as I can take the taxonomy of this genus, it appears that this species is very common on all sorts of pines in North America. It is most abundant on pines in ornamental landscapes, but I have seen it on native pines in the mountains as well.