Butterflies This section is rather arbitrarily split into six sub-sections as shown below. Within the first four of these the images are organised alphabetically by Common Name e.g. Small Skipper comes after Grizzled Skipper. In both Others sub-sections the Family Name (Genus) takes precedence, followed by the Species Name. In this way similar species are, generally, close together for easier comparison e.g. Red Admiral comes under Admiral, Red. To enlarge a thumbnail left click on an image when the pointed finger appears (or double-tap on Touchscreen). This also gives access to a slideshow where there may be further information.
The most useful general book for European Butterfly identification is Collins Butterfly Guide – Tolman and Lewington, although the text can seem a little confusing at first.
The FSC weatherproof guide to the Butterflies of Britain is very useful, as is the Caterpillars of the Butterflies of Britain and Ireland.
For Spain, there is a very good Facebook group: Mariposas diurnas de Andalucía. For anywhere further afield I have relied on the Internet. Some of the links are indicated on the main Insect page.
All images are my own.