Brachynemurus abdominalis

Snap-trap Antlion
Brachynemurus abdominalis

Snap-trap Antlion Brachynemurus abdominalis female
Snap-trap Antlion Brachynemurus abdominalis female from Manitoulin Island, July 04, 2007.
Snap-trap Antlion Brachynemurus abdominalis female
Snap-trap Antlion Brachynemurus abdominalis female from Manitoulin Island, July 04, 2007.
Snap-trap Antlion Brachynemurus abdominalis male
Snap-trap Antlion Brachynemurus abdominalis male on Cinquefoil (Potentilla) in Goron Woods, South meadow, Wheatley, Ontario June 22, 2007.
Snap-trap Antlion Brachynemurus abdominalis male
Snap-trap Antlion Brachynemurus abdominalis male on Cinquefoil (Potentilla) in Goron Woods, South meadow, Wheatley, Ontario June 22, 2007.

Note: The male is from Wheatley, Ontario. The female is from Manitoulin Island.

Identification:
Head: Pale yellowish-brown with dark streaks and spots. Large protruding, multi-colored eyes.
Antenna: Segments brownish-yellow, ringed with dark brown. Tips clubbed (clavate), light yellowish-brown.
Thorax: Pale yellowish-brown; streaked darker. Neck (pronotum) with 2 or 3 dark streaks.

Snap-trap Antlion Brachynemurus abdominalis female wing close-up
Close-up of female wing Snap-trap Antlion Brachynemurus abdominmalis showing small spots on lower row and larger spots on upper row.

Wings: Female has clear wings with deep black veins. Outside (or lower) wing border has dark spots with white dashes in between; black spots are small on first row and large on next row. Both male and female have a faint white spot (stigma) near wing tip; stigma is usually larger on the female. Male wings can be same as the female or entirely tinted a faint yellowish with obvious yellow, long veins.
Legs: Legs thick and short; bright yellow (male’s pale yellow), speckled with black; feet whitish, spotted with black.
Abdomen: Female abdomen yellowish-brown, with darker streaks; tip of abdomen just reaching to wing tips. Male abdomen extending 1/3 past wing tips; last half of abdomen more reddish-yellow than female. 

Similar Species:
B. longicaudus has no white dashes in between spots. Male unmistakable – abdomen twice as long as wings.
The Clouded Antlion B. nebulosus female has dark wings with darker blotches (not spots) and some white on cross-veins. Male wings the same, but a bit darker and with less white.
B. signatus male and female have black-veined wings with no marks.

Size: Female 23 mm long. Male 25 to 33 mm long. Larva 10 mm long 

Flight Time: June to mid-August.

Habitat: Meadows & forest edges with sandy, bare soil.

Food: Larva eat aphids, mites, mealy bugs and particularly ants. Adults feed on nectar.

Life Cycle: Larvae are found in open sandy areas, living just beneath the sand surface. They do not form pits like the Common Antlion Myrmeleon immaculatus.

Comments: Essex County – Ojibway Prairies and Point Pelee National Park.  Also found at Long Point, Ontario.

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

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