Megachile campanulae

Bellflower Resin Bee
Megachile campanulae

Identification:

Leaf-cutter Bee Megachile campanulae female on Everlasting Pea. July 16, 2009 Wheatley, Ontario.
Leaf-cutter Bee Megachile campanulae female on Everlasting Pea. July 16, 2009 Wheatley, Ontario.

Head: Black with scattered white hair on face. Top of head mostly bald. Mandibles black, 4 blunt teeth on female, 3 on male. Cheeks about equal to eye width; a few white hairs on lower half. Male has more hair on face and lower cheeks.
Antenna: Black, tips long. Female segments about the same size; male segment 1 very short.
Thorax: Black, bordered with scattering of white hair. Thorax sides scattered white hair, more dense around tubercles (pronotal lobe) which is a white crescent. Male has slightly more hair.
Wings: Wing knob black. Wings clear, darker at tips. Veins blackish.
Legs: Black with scattering of white hair. Female has hair more yellowish-brown and dense on feet. Underside of hind foot segment 1 (basitarsi) darker golden. Male feet dense white.

Megachile campanulae female stripes appear split.
Megachile campanulae female stripes appear split.

Abdomen: Black, long, narrow, parallel-sided on both male and female. (see Life Cycle)
Segment 1 has short, dense white hair band at side edges.
Segments 2 to 4: Very narrow hair band at the base of each segment. Each segment also has an indented line starting at the lower segment edge on each side and curving upward to the middle of the segment. These indentation are covered with thick, wide white pile at the side edges and fade out towards center.  Because the indented pile stripe is so close to the base stripe on the next segment, they have the appearance of a somewhat divided single stripe.
Segment 5 has only faint traces of a hair band at the base on female, more obvious on male.

Leaf-cutter Bee Megachile campanulae female on Everlasting Pea. Aug 16, 2013 Wheatley, Ontario.
Leaf-cutter Bee Megachile campanulae female on Everlasting Pea. Aug 16, 2013 Wheatley, Ontario.

Segment 6 covered with very short whitish hair, tip curves slightly upward on female; entire segment curved under on male with long white hair. Underside covered with yellowish-white hair (pollen basket) on female. Underside of male has only 3 visible segments with long white hair.

Similar Species: Very similar to Heriades carinata which does not have split stripes on abdomen. Otherwise almost identical.

Size: Female 10 to 12 mm. Male 8 to 9 mm.

Habitat: Meadows

Food: Flower nectar.

Flight Time: July to September

Leaf-cutter Bee Megachile campanulae female on Jerusalem Artichoke. Sep 12, 2013 Wheatley, Ontario.
Leaf-cutter Bee Megachile campanulae female on Jerusalem Artichoke. Sep 12, 2013 Wheatley, Ontario.

Life Cycle: Nests made in wood, dead stems (like Sumac), clay (1 report) or plant debris. Megachile females that use resin all have parallel-sided abdomens, not cone-shaped like the rest of the Megachile. Cells are made from resin, small pebbles and mud. Although classed as a leaf-cutter, no leaves are used in cell construction.  2 to 9 cells per nest, with long partitions. Over-winters as larva in a sturdy white cocoon, not pupating until spring the next year. One generation per year.
Parasitized by the Cuckoo Bees Stelis louisae and Coelioxys modesta.

Comments: Essex County – Point Pelee. Niagara, Waterloo and Cayuga.

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

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