For a number of years there has been no single and comprehensive work available for the identificationof the aphid species occurring in the British Isles. The books of Buckton and Theobald, for many years the standard reference work on the British fauna, are now of mainly historical interest, and their use leads only to frustration because of the great advances made in the study of aphid systematics and nomenclature over the last 50 years, mainly as a result of improved techniques for the handling of aphids as subjects for microscopy..
the first part of the present treatment (Stroyan, 1977) dealt with the two families Chaitophoridae and Callaphididae. In the second part, presented here, I have felt it best to tackle the groups that follow immediately after the Callaphididae in the current edition of the ‘Check List of British Insects’ (Kloet & Hincks, 1964), even though these groups contain the least effectively worked out genus of aphids occurring here, Aphis Linnaeus, and though recent ideas on aphid phylogeny may well lead to changes in the order and relationships of various family-groups over the next few years.
There has been no complete review or handbook of the 90 British taxa of Aphis since the treatment of the genus by Theobald in 1927, when far fewer species were known, and many were confused or misidentified. Neither has there been a comprehensive treatment that works well for any world region since the books of Palmer (1952) and Shaposhnikov (1964), both of whose keys are deficient in a variety of ways. I therefore believe that, imperfect as the present attempt certainly is, it will serve as a basis for future research into the taxonomy of British Aphis species, and thus go some way to filling the most conspicuous gap that still exists in the knowledge of our aphid fauna. Because of the size of this gap I have given a much fuller list of references to previous literature than I gave in the earlier part, as well as maintaining the rather detailed generic descriptions that I found necessary there.
No section has been incorporated dealing with the techniques of handling and mounting aphid material, since these have been well summarised in Chapter 1 of the handbook Aphid Technology edited by van Emden (1972).