Roesel’s katydid (Metrioptera roeselii) is a small, short-winged, shield-backed katydid. It is native to Europe, where it is called Roesel’s bush-cricket. In 1953 it was reported at two locations in Quebec. These were the first North American records. It now occurs in southern Canada from Prince Edward Island to Manitoba, and in the northern United States from Maine to Minnesota south to Maryland and Iowa. Adults are found from late June through October in meadows and grassy fields, at the margins of pastures, and in ditches and roadsides. They require a moist area with tall grasses that is undisturbed by mowing or grazing.
Adults are ½″ to 1″ in length and usually dark brown, sometimes yellow, rarely green. The plate covering the first segment of the thorax is brown on top, black on the sides, and cream-colored around the margins of each side. There are three pale green or yellow spots on each side of the thorax. Most adults have short wings and cannot fly. In most years, only about 1% have long functional wings. In years with exceptionally hot summers there are more winged adults.
Pond olive (Cloeon dipterum) is a small minnow mayfly. It occurs throughout Europe, where it is native, and in Asia and North America, where it has been introduced. The earliest North American record is from Illinois in 1953. It is now widespread across the continent. In the United States it is currently mostly restricted to the northeast and to Washington state. It is rare in Minnesota. Nymphs are found mostly in ponds, but also in the shallow margins of lakes and in slow areas of rivers and streams. They feed on algae, small aquatic organisms, and organic debris. Adults are found on vegetation near ponds. They do not feed and seldom live more than 1 or 2 days.
Adults are reddish-brown and have 2 very long hair-like tails at the end of the abdomen. The compound eyes on the female are on the sides of the head. On the male the compound eyes have additional large, orange, turban-like parts that meet at the top of the head. These adaptations are said to allow the male to isolate in a swarm females that are not yet paired with another male. Some authors say that pond olives have no hindwings. Carl Linnaeus in 1761 described the hindwings as “hardly present.”