Category Archives: Insects

Pond olive (Cloeon dipterum)

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pond olive
Photo by Alfredo Colon

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.”

http://www.minnesotaseasons.com/Insects/pond_olive.html

Canada darner (Aeshna canadensis)

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Canada darner
Photo by Wander Without Wifi

Canada darner (Aeshna canadensis) is a large mosaic darner. It occurs across the northern United States and southern Canada. It is the most common blue darner in Minnesota, where it occurs throughout the state except for the western prairie counties. It is a late-season dragonfly, not appearing until late June and flying to the end of September.

Adults are about 2¾″ long. The body is dark brown with blue, green, or yellow markings that darken in cool temperatures. Males always have mostly blue markings. Females have three color forms; blue, green, and yellow. Most females are green form. Blue form females are rare.

There are at least ten blue darner dragonfly species found in Minnesota and they are difficult to tell apart. Canada darner is most easily distinguished by the lateral stripes on the thorax. The front stripe is deeply notched, is narrowed toward the top, and has a narrow rearward extension (flag) at the top. The rear lateral stripe is not notched. Like all mosaic dragonflies, there is a black T-shaped spot on the upper part of the face just below where the eyes meet. This is best seen when viewed from above. There is no bold black horizontal stripe across the middle of the face.

http://www.minnesotaseasons.com/Insects/Canada_darner.html

Reddish-brown stag beetle (Lucanus capreolus)

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reddish-brown stag beetle
Photo by Plannine

Reddish-brown stag beetle (Lucanus capreolus) is relatively large beetle. It occurs in the United States east of the Great Plains and in adjacent Canadian provinces. It is found around decaying logs and stumps in deciduous forests, parks, and neighborhoods with trees. Larvae feed on decaying wood, adults feed on tree sap. The name “stag beetle” refers to the oversized mandibles on some males that resemble deer antlers. Another common name for this beetle is pinching bug. The mandibles look fierce and are used to fight other males over a female. When confronted, it will rear back threateningly with its mandibles open. However, when handled by humans, it can give no more than a mild pinch.

Adults are reddish-brown and up to 1½″ long, not including the mandibles. The antennae have 10 segments, are abruptly bent, and are expanded (clubbed) at the tip. The body appears smooth but is densely covered with very fine punctures. The third and largest segment of each leg is distinctly pale.

http://www.minnesotaseasons.com/Insects/reddish-brown_stag_beetle.html

Coppery leafhopper (Jikradia olitoria)

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coppery leafhopper
Photo by Alfredo Colon

Coppery leafhopper (Jikradia olitoria) is a common, medium-sized, slender leafhopper. It occurs throughout the eastern half of the United States and in adjacent Canadian provinces. In Minnesota it has been recorded only in the southeast quarter of the state. Little is known of the biology of leafhoppers in the subfamily Coelidiinae. Coppery leafhopper is said to feed on woody species. In 1975 it was suggested that the subspecies Jikradia olitoria floridana was a vector of strawberry pallidosis. This was later rejected when in 2006 the greenhouse whitefly Trialeurodes vaporariorum was discovered to be the true vector of the disease.

Coppery leafhopper adults are about ¼″ long and variable in color. They are usually light brownish-gray to medium brownish-black, sometimes dark and bluish, sometimes entirely light brownish-yellow. Females always have pale wing bands. Males are always dark brown or rusty brown and have no pale bands.

http://www.minnesotaseasons.com/Insects/coppery_leafhopper.html

Taschenberg’s long-necked ant (Dolichoderus taschenbergi)

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Taschenberg’s long-necked ant
Photo by Luciearl

Taschenberg’s long-necked ant (Dolichoderus taschenbergi) is a small odorous ant. It occurs in the United States from Maine to North Dakota, south to Georgia and Louisiana, and in Canada from Nova Scotia to Manitoba. It is uncommon throughout its range but is most abundant in the north. It is found in open areas including old fields, woodland edges, and bogs. It forms huge colonies, often with multiple queens and more than 10,000 workers. It constructs igloo-shaped dome nests, 2″ to 8″ in height, using grasses, sphagnum mosses, spruce and pine needles, and other shredded vegetation. It the spring it can sometimes be found massed aboveground warming in the sun.

Workers are uniformly colored. The overall color is sometimes interpreted as “dark brownish-black”, sometimes as “all black”, sometimes as “jet black”. The head and front part of the body are dull, the rear of the body is shiny. The last segment of the front part of the body (propodeum) is an important identifying feature. When viewed from above, the propodeum is squarish, about as long as wide. When viewed from the side, the propodeum is distinctly concave and has the appearance of a bottle opener.

http://www.minnesotaseasons.com/Insects/Taschenbergs_long-necked_ant.html

Sunflower tortoise beetle (Physonota helianthi)

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sunflower tortoise beetle
Intermediate Adult

Sunflower tortoise beetle (Physonota helianthi) is a small leaf beetle. It occurs in the United States east of the Great Plains and in adjacent Canadian provinces. It is uncommon throughout its range.

There are three color phases that each adult undergoes. The teneral adult, freshly emerged from the pupal stage, is soft bodied and dingy white or ivory. The intermediate adult is black and white with numerous spots. This phase lasts about three weeks. The mature adult is entirely iridescent green. The upper thoracic plate and the two hardened wing covers each have a semi-transparent covering over the entire surface.

sunflower tortoise beetle
Mature Adult

Both larvae and adults feed on the underside of leaves. They occasionally defoliate the plant and can be a major pest. Larvae carry dried fecal matter over their body, presumably as a form of camouflage. The fecal matter is attached to a forked appendage on the last abdominal segment, and is held suspended over the body.

http://www.minnesotaseasons.com/Insects/sunflower_tortoise_beetle.html

Armyworm moth (Mythimna unipuncta)

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armyworm moth
Photo by Alfredo Colon

Armyworm moth (Mythimna unipuncta), also called true armyworm and the white speck. is a migratory wainscot moth. It is medium-sized for a moth, large for a wainscot moth. It occurs in Europe, northern Africa, Iceland, North America, Central America, and northern South America. It is common throughout the United States and Canada, common and sometimes abundant in Minnesota. It does not survive cold winters. Adults migrate south in the fall and a later generation disperses north in the spring. Adults are found in Minnesota from March to November. Caterpillars feed on leaves and sometimes seed heads of mostly grains and other grasses, but also many broadleaf plants close to their infestations. After defoliating a stand of plants, they will move as a group to a nearby stand and resume feeding. They are often a serious agricultural pest, especially on wheat and corn.

Armyworm moths are ¾″ to 1″ long. Their forewings are tan with dark peppering and a small but conspicuous white spot. The caterpillar is up to 2″ long.

http://www.minnesotaseasons.com/Insects/armyworm_moth.html

Mid-winter boreus (Boreus brumalis)

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mid-winter boreus
Photo by Luciearl

There are fifteen species of snow scorpionflies (Family Boreidae) worldwide, thirteen species in North America, two in eastern United States including Minnesota. The two species in our state are both in the genus Boreus and are easily told apart by their color.

Mid-winter boreus (Boreus brumalis) is a small snow scorpionfly. It is common in the United States from Maine to Michigan, south to Tennessee, and in Canada in Nova Scotia and Ontario. There are isolated populations in Illinois, Wisconsin, and Minnesota. They are found in deciduous woodlands that have moss on the ground. Larvae live in moss and prey on small insects and other animals found in the moss, and possibly also on the moss. Adults prey on small insects and other animals found hibernating under stones and moss. They are seen on the surface of the snow on winter days when the temperature is above freezing feeding on other winter insects.

http://www.minnesotaseasons.com/Insects/mid-winter_boreus.html

Elm leafminer (Fenusa ulmi)

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elm leafminer
Elm leafminer. Sorry for the poor quality of this photo. If a picture should be worth a thousand words, this one is worth a few hundred at most.

Elm leafminer (Fenusa ulmi) is a very small common sawfly. It is native to eastern Europe and Scandinavia. It was brought to North America most likely on imported elms. It now occurs in the United States from New England to the upper Midwest, in the Pacific Northwest, and in southeast Canada. Based on the scarcity of reports, it is still relatively uncommon in Minnesota.

Due to the small size of the adult, elm leafminer is most often identified by the damage the larva causes to its host plant. Mines are seen from mid-May to early June on American elm and slippery elm. The larva feeds between the upper and lower surfaces of the leaf. It creates a serpentine mine at first. That soon develops into a small blotch between two lateral veins, later into a large blotch on one side if the midrib. The mines are clear and the flattened, whitish-green or yellowish-white larva can be seen when viewing the upper side of the leaf. The infected part of the leaf turns brown and eventually falls off. A heavy infestation may cause the entire tree to defoliate, but the infected tree flushes again and survives.

http://www.minnesotaseasons.com/Insects/elm_leafminer.html

American dagger moth (Acronicta americana)

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American dagger moth
Photo by Alfredo Colon

Dagger Moths (genus Acronicta) is a large genus with about 150 species worldwide, more than 73 species in North America north of Mexico. At least 28 species have been reported in Minnesota. The common name refers to a black, dagger-like dash on the forewings of many of the species. Most are gray with darker gray markings, and are difficult to identify.

American dagger moth (Acronicta americana) is the largest dagger moth in eastern United States. The adult is up to 1½″ long and has a wingspan of up to 2½″. It is gray or brownish-gray with dark markings and a black “dagger”. It is found in deciduous woodlands and forests across the United States and southern Canada. It is common and sometimes abundant east of the Great Plains, common in Minnesota.

The caterpillar is large and is covered with yellow or white hairs. It has two pairs of long black lashes near the front of the abdomen and a single thicker lash near the end. The lashes are tight groups of bristles. When the caterpillar is handled the bristles break off and embed in the skin of the handler. They contain a toxin which causes stinging and burning and can develop into a rash.

http://www.minnesotaseasons.com/Insects/American_dagger_moth.html