Aphidoidea Research at SEL, USDA (links to .pdf files of papers on the taxonomy of aphid pests on various crops)
The United States National Collection of Aphid Photographs (Searchable database of aphid photographs, including several species found in this region)
Pest and Disease Image Library (PADIL) (Images and factsheets on pests and diseases, including several species of aphids)
Identification: Key to Aphids Commonly Found in San Joaquin Valley Alfalfa and Cotton
Coccinellidae of the Indian subcontinent (Image gallery of common lady beetles of the Indian region)