This patch of cloud formation is actually altocumulus stratiformis translucidus lacunosus and is the thinnest of all altocumulus clouds. The stratiformis variety is due to the cloud being in extended sheet whilst translucidus is due to allowing light to pass through it hence having that bluish appearance. Actually the photographed cloud was in a very isolated patch in which the tree branch is big in comparison making it quite rare. Being true to its characteristics, the cloud patch was characterized by patches of somewhat regularly arranged round holes having frindged edges as if something is tearing this cloud apart from the inside out probably due to lack of instability to sustain it.
Very rare clouds were spotted during the time when the photo was taken vide this page ‘Horseshoe Cloud’ whereby the day’s weather situation was explained in some detail. The World Meteorological Organization codes such clouds as CM = 4 because of their continually changing appearance. The first thumbnail is a wide angle view of the same cloud showing altocumulus translucidus cloud and almost becoming irridescent whilst the second thumbnail is an iphone zoomed in version of the photographed cloud to attempt to bring out all the details, unlucky that I did not have my professional camera with me as the cloud just formed by chance. Throughout the photos notice how the cloud is changing rapidly almost within several seconds. The third thumbnail is the weather sounding of the day.