Chinche roja del melocotonero/Apricot tree stinkbug
This is a species of ground bugs belonging to the family Lygaeidae. They reproduce in Malvaceae palnts but then move onto fruit trees. I was really surprised to see the amount of them in this tree. They are obviously a pest.
Habitat: Fruit trees: oranges, apricots, apple trees. Present in the South of Europe. These were seen in Calpe, Alicante, Spain (Nov, 2013).

"Oxycarenus lavaterae" is a species of "ground bug" belonging to the family Lygaeidae, subfamily Oxycareninae. It is found on and feeds upon plants in the Malvaceae family, such as Lavatera, Althea, Hibiscus, and Malva. It forms aggregates to winter over, typically on lime trees.