17-10-2019 OLIVA MARJAL, VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

5-5-2019 ULLAL DE BALDOVI , VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

11-3-2019 VAL D'EBO, VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

1-11-2018 MONTE CORONA, VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

24-10-2018 DEVESA, VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

28-9-2018 ALBUFERA, VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

8-7-2018 TABLAS DE DAIMIEL, LA MANCHA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

4-5-2018 ULAL DE BOLDOVI, VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

17-7-2017 VILLALONGA RESERVOIR, VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

2-10-2015 RIVER JUCAR, VALENCIA - CLOUDED YELLOW BUTTERFLY (Colias croceus)

Colias croceus, clouded yellow, is a small butterfly of the family Pieridae, the yellows and whites.

Colias croceus is one of the most widespread species in Europe. The common clouded yellow's breeding range is North Africa and southern Europe and eastwards through Turkey into the Middle East, but it occurs throughout much of Europe as a summer migrant, in good years individuals reaching Scandinavia. In Asia, its range extends into central Siberia in the north and barely into India in the south; it is not found in Central Asia.

This species is primarily an immigrant to the UK, originating from southern Europe and northern Africa. In the UK they can be seen on the south coast almost every year in varying numbers, and regularly breed there. Occurrence in the rest of the UK varies considerably from year to year, but they are increasingly observed as far north as Dumfries and Galloway. It has also been recorded in Ireland from the Raven, Co. Wexford, to Belfast, Co. Down.

A truly migratory European butterfly, this species is famous for occasional mass migrations and subsequent breeding, which are often referred to in the United Kingdom as "clouded yellow years". Notable clouded yellow years include 1877, 1947, 1983, 1992, 1994, 1996 and 2000.