polished lady beetle

not listed

NNR - Unranked

not listed

Polished lady beetle is a small ladybird beetle. It occurs in most of North America from southern Canada to northern Mexico. It is common in the east, including the eastern half of Minnesota, less common in the Great Plains, uncommon in the arid southwest.

The body is almost round, very convex, ⅛″ to ¼″ (3.7 to 5.7 mm) long, and ⅛″ (3.1 to 4.2 mm) wide.

The head is shallowly inserted into the thorax, but is visible from above. The top of the head (vertex) and the compound eyes are black. The orbital groove, on the face bordering the compound eye, is white. On the male, the face is white. On the female, it is black.

The upper thoracic plate (pronotum) is convex, wider than long, and distinctly margined on the sides. It is mostly black with white front and lateral margins. On each side near the head there is an outward-curved white mark that, together with the curved white lateral margin, forms a ring that is not completely closed. There is also a short white line in the middle that merges with the front white margin. The surface of the pronotum is leathery, covered with minute cracks, and dull, not shiny. The exoskeletal plate between the wing bases (scutellum), is small, triangular, and black. On the underside of the thorax, the rear margin of the first segment (prosternum) is rounded, not protruding, and the front margin of the second segment (mesosternum) is truncate, not deeply notched.

The hardened wing covers (elytra) are reddish-orange and entirely free of spots. They completely cover the abdomen. The outer margins are weakly extended horizontally. The surface does not have grooves or rows of punctures. Rare individuals will have one or more black spots, but these are not arranged symmetrically. They are due to damage to the developing pupa.

The legs are light yellowish-brown. The fourth segment (tibia) on the middle and hind legs have two spurs at the tip. The last part of each leg (tarsus), corresponding to the foot, has four segments, but the third segment is very short and tucked within the extended lobes of the second segment, making the leg appear to have only three segments. The tip of the last tarsal segment on the middle and hind legs has a pair of claws. Each claw has a large tooth at the base that is nearly square with rounded corners.

Total length: ⅛″ to ¼″ (3.7 to 5.7 mm)

Spring and summer

Aphids

Sources

7, 24, 27, 29, 82.

Cycloneda munda polished ladybird beetle

Cycloneda munda, polished ladybird beetle, photographed on Barnes Prairie, Racine Co., WI on June 23, 2021.

Location: Barnes Prairie, Racine Co., WI

Cycloneda munda, polished ladybird beetle, photographed on Barnes Prairie, Racine Co., WI on June 23, 2021.

Location: Woodbury, Minnesota