Red and black is the most common ladybug color combination. The Seven-Spotted ladybug, or C-7, originated in Europe but has been naturalized in the U.S., and is bright red and dome-shaped with seven black spots on each side. They are among the first to be seen in spring, as are Harmonia axyridis or Asian Ladybugs, which can grow to more than 1/4 inch in length, making them one of the largest of the species. The five black spots toward the rear of their thorax form an M. Asian Ladybugs can be an unwanted pest because they are attracted to light-colored walls of homes and often enter homes; the secretions from their legs can stain carpets.
The Coleomegilla maculata, or C-Mac ladybug, is also known as the pink spotted ladybug. It eats pollen, mites, insect eggs and larvae and aphids. Its larvae also eats aphids. The pink and black lady beetle is more of an oblong shape. They are used in potato fields for control of the Colorado Potato Beetle.
Hippodamia convergens, or the Convergent Lady Beetle, a medium-sized ladybug, is orange with black spots in various patterns on its back. It is sold commercially to farmers for the control of aphids. Coccinella septempunctata, or the Seven-Spotted Lady Beetle, or C-7, can be red or orange, and is identified by the seven spots on each side of its body.
Unlike most other species of lady beetles, the yellow ladybugs may actually harm the crops. The Mexican Bean beetle is easily recognized by the eight spots on each side of its body. It feeds on green beans. Squash beetles have seven spots and eat squash, pumpkins and cantaloupe. Their color ranges from yellow through orange.
Ladybugs can also have as few as two spots, and a solid body color of yellow through red, or can be black with red or orange spots. Insects with colors other than yellow through red and black are most likely not lady beetles.