impressive meloine beetle

not listed

NNR - Unranked

not listed

Impressive meloine beetle is an elongated, medium-sized, blister beetle, ½″ to 1″ in length. Males are smaller than females.

The head, body, and legs are usually brilliant metallic blue, violet, or green, sometimes black.

The head is more or less rectangular when viewed from above. It is 70% to 80% as long as wide and is abruptly constricted behind the eyes forming a short neck. It is sparsely covered with scattered, fine pits. The upper margin of the eye is nearly straight. The antennae are bead-like and have 11 rounded segments. On males, the antennae are bent in the middle with segments 5, 6, and 7 forming a C-shaped kink. Segment 5 is enlarged and flared outward at the end.

The thorax is narrower than the head and abdomen. The upper plate covering the thorax (pronotum) has straight sides that converge toward the rear (posteriorly). It is sparsely covered with scattered, fine pits.

The abdomen is oval-shaped. There are no hindwings. The hardened forewings (elytra) are small, much shorter than the abdomen, and overlap at the base.

The legs are long and slender. The femur of the front leg does not have a patch of hair. A outer spur at the end of the fourth leg segment (tibia) of the hind leg projects toward the rear.

Total length: ½″ to 1″

August to October

They are found on the ground or on low foliage.

When threatened or mishandled blister beetles (family Meloidae) exude a yellowish liquid from their joints. The thick oily substance contains the toxin cantharidin, which causes blistering on human skin.

The female deposits eggs on foliage or in a 1″ deep burrow in the ground. After the eggs hatch the larvae pass through four stages. The first stage (triungulin) is mobile on plants. The entire hatched group climbs to the top of a plant and forms a cluster in roughly the shape of a female ground bee. It then exudes a chemical scent that mimics the pheromone of a female bee. When a male bee attempts to mate with the mass, some of the larvae attach themselves to its hairs. When the male mates with a female bee some of the larvae attach to the female. These remain on the female while she builds a nest, then detach and begin feeding on newly laid bee eggs. The second stage of this larva is a short-legged grub, called “first grub”, that spans four molts (instars). This stage feeds on honey in the nest. The third stage/sixth instar, called coarctate, is legless and immobile. The larva usually overwinters in this stage is a state of low metabolic activity (diapause), though it may overwinter in other stages. The fourth stage/seventh instar, called “second grub”, is a nonfeeding form that resembles the first grub. This stage feeds on honey and stored pollen. it is soon followed by the pupal stage.

Favorable environmental conditions may cause the larva to skip the coarctate stage. Adverse conditions may cause it to molt from the second grub back to the first grub, delaying the pupal stage until conditions improve.

Bee eggs and stored food in ground-nesting bee nests.

Plant foliage and flowers of many plants, including field mustard, hepatica, spotted touch-me-not, tall buttercup, bristly buttercup, Irish potato, virgin’s bower, and eastern white pine.

Sources

7, 24, 29, 30.

Infrequent

impressive meloine beetle

Have sighted several over the last three days.

Found at 9:10pm in the outskirts of town.

Near Otter Lake

Eden Valley

Male

Male and Female

Location: 24651 Edenvale Trail, Elko New Market MN 55020

Location: Fogard Lake (Otter Tail County), MN

Have sighted several over the last three days.

Location: Columbus, IN

Location: Cottage Grove, Oregon

Found at 9:10pm in the outskirts of town.

Location: Kaplan's Woods Owatonna, MN

Location: Kaplan's Woods Owatonna, MN

Location: Ely, MN, St. Louis Co.

Found this one near Bearhead Lake State Park

Location: Whitetail Woods Regional Park

Location: Lino Lakes, Mn

Near Otter Lake

Location: Meeker County

Eden Valley

Location: Henderson Township, Sibley County, MN

Location: Big Lake, Sherburne County

Location: Miesville Ravine Park Reserve, Miesville, MN