Acupalpus testaceus

Ground Beetle
Acupalpus testaceus

Identification:

Ground Beetle Acupalpus testaceus about 4 mm. came to moth lights July 10, 2011. Wheatley, Ontario.
Ground Beetle Acupalpus testaceus about 4 mm. came to moth lights July 10, 2011. Wheatley, Ontario.

Head: Head reddish-yellow, shiny; not as wide as thorax. Large eyes, protruding. Last whisker (palpi) long, slender and pointed, lighter yellow, same as legs. Mandibles large, tips dark.
Antenna: Brown, 11 segments, extend almost to end of thorax (pronotum). Segments 1 to 2 or 3 pale.
Thorax (pronotum): Reddish-yellow, shiny and squarish; widest before middle. Smooth with a incomplete indented line down middle. Hind margins rounded. Slight shelf or rim along side edges. Hind margin has large indented or impressed spots at center.
Wings (elytra): Reddish-yellow; wider than thorax, sides straight (parallel), then tapering to tip. Sometimes with a large, slightly darker, faint V-shape mark along base, and sometimes some slightly darker, faint blotches on lower half of wings. Indented groves very narrow (about 10) running length of wings. Tip bluntly rounded. V-shape at middle of base (scutellum) barely visible to absent.
Legs: Pale brownish-yellow, slightly lighter than body colour. Hind feet short, first 3 segments combined are as long as last segment.
Abdomen: Dark on underside.

Similar Species: The other reddish Acupalpus species all have dark heads. Bradycellus insulsus has very dark, obvious marks on the wings and scutellum.

Size: 3 to 4 mm.

Habitat: Carolinian forests, in leaf litter.

Food: Assumed to eat smaller insects.

Flight Time: June to August

Life Cycle: Unknown.

Comments: Essex County – Point Pelee National Park.

For information on synonyms, references and type specimens see next page