At Qaryat Al Ulya Pivot Irrigation fields there were a large number of Clouded Yellow butterflies flying a rung the Alfafa crops. The range of the Clouded Yellow Colias croceus is across Southern and Central Europe to North Africa, Iran and the Arabian Peninsula. In Saudi Arabia it is common at Tuwayq Hills and is abundant in all major cultivated eastern oases such as Al Hassa, Quatif, Taraut Island and Safway, favouring Medicago sativa fields. Pivot irrigation fields are also good areas to find the species. Small isolated populations also exist around Manifa, north of Jubail, on beds of annual winter legumes growing in the hollows between coastal sand dunes with the populations supplemented by migrants. They are 45-54 mm in size and most have an orange-yellow ground with broad black borders to wings. They occurs mainly from December to early May but at Manifa during February and March. It has a characteristic to and fro flight over low vegetation where it frequently settles on sweet basil Ocimum basilicum flowers in oases.
