West Coast lady it lacks obvious ventral eyespots on the hindwings; there are two large ones on "V. virginiensis" and four small ones on "V. cardui". Like the latter, it also lacks a white dot in the pinkish-orange subapical field of the ventral and dorsal forewings. Its upperwing coloration has the purest orange of the three; the American painted lady is usually quite reddish. A less reliable indicator is the row of black eyespots on the dorsal submarginal hindwing. These are usually of roughly equal size in "V. cardui" and lack blue centers, though the summer morph may have a few tiny ones.
Brachycaudus cardui viral disease affecting plums, damsons, peaches, apricots and some other plants. Brachycaudus cardui Brachycaudus cardui is a species of aphid, commonly known as the thistle aphid or the plum-thistle aphid. It infests trees in the genus "Prunus" in the spring and autumn, and mostly plants in the aster family in the summer. The viviparous wingless females of "B. cardui" have an oval or pear-shaped body and grow to a length of from . The colour may be green, yellowish, reddish or brown. The abdomen has a dark, shining patch on the dorsal surface, a fact which distinguishes this species from