In my opinion, at the field guide level, you won’t beat the best English guides to the butterflies of Europe. There do exist Specifically Spanish guides - I have the first edition of this one:
https://m.casadellibro.com/libro-las-ma ... 89/2632131, which has the added advantage of including moths - but I’ve never really used it.
However, for the Lycaenids, I can recommend this:
https://www.nhbs.com/biologia-y-ecologi ... noles-book. It’s exactly what you say you don’t want - large format, hardback and without maps - but a wonderful book.
Spain has a lot of rare endemics. They don’t advertise their locations, quite rightly, as the country also attracts a large number of collectors.
Be aware you need a licence to carry a net in Spain, on pain of a fine up to 10 000 euros. I applied for and got one some years ago. It covered just one region, for one year, and required me to have professional/university referees.
Guy