Epeolus scutellaris

Cuckoo Bee
Epeolus scutellaris


Cuckoo Bee Epeolus scutellaris female
Cuckoo Bee Epeolus scutellaris female on grass blade, Sep 03, 2009 Wheatley, Ontario.
Cuckoo Bee Epeolus scutellaris male
Cuckoo Bee Epeolus scutellaris male on Black-eyed Susan Aug 21, 2009. Wheatley, Ontario.

Head: Black with yellowish-white hair around antenna bases in female; across mid-face in male. Cheeks narrow, female about half as wide as eye width; males only ¼ as wide as eye width. Mandibles reddish on female; all black on male.
Antenna: Base (scape) reddish to yellowish-brown. First 3 segments reddish on female. Rest dark brown-black. All dark brown-black on male.
Thorax: Rough with yellowish-white hair. Collar stripe uninterrupted. Segment 1 (scutum) has two stripes, one each side of mid line. Segment 2 (scutellum) has deep groove down centre; brown in male, side points (axillae) reddish-brown; all entirely red in female. Axillae are large and project past end of scutellum. Thorax sides rough, tubercles reddish-brown, surrounded with yellowish-white fringe. Bands of yellowish-white hair under wing base and transverse across centre of thorax side; lower half bare. Underside of thorax densely hairy.
Wings: Wing knob (tegulae) reddish-brown. Wings lightly tinted, becoming slightly darker at tips. Veins brownish. Stigma amber.
Legs: Legs reddish-brown. Male has underside of mid and hind thigh (femora) dark. Feet reddish. Spurs dark.
Abdomen: Black with pale yellow stripes along lower borders of segments.
Segment 1 has two stripes which are slightly or not joined at side edges. Lower stripe has a very narrow interrupt at centre.
Segment 2 stripe also slightly interrupted at centre; entire in male.
Segments 3 to 5 have uninterrupted stripes.
Segment 5 stripe quite wide and indented at centre on lower margin.
Tip is twice as wide as long with a bright white crescent in female.
Male tip rounded, black or orange.
Underside shiny, no pile. Segments 2 and 3 have white stripes.

Similar Species: E. pusillus has thorax sides entirely covered with hair, abdominal stripes on segment 1 are connected at side edges.
Female thorax segment 2 (scutellum) is black with red points (axillae) in E. pusillus; entirely red in E. scutellaris.

Size: Female 9 to 10 mm.   Male 7 to 9 mm.

Flight Time: July to September.

Habitat: Forest edges and meadows.

Food: The larva are cleptoparasites of Plasterer Bees Colletes. Adults eat nectar.

Life Cycle: All species of Epeolus are cleptoparasites of Plasterer Bees Colletes. The female finds Plasterer bee nests, enters and lays an egg. When larva hatch, it kills the Plasterer bee egg, and feeds on the stored pollen, nectar. Host is Colletes simulans armatus per Ascher.

Comments: Essex County – Ojibway Prairies, Point Pelee National Park. Kent County – Rondeau Provincial Park. Also in southern Michigan.
“During rainy or windy weather, this insect secures itself to the edge of a leaf or to the small branch of a bush, by its mandibles, retracts the feet to the body, and projects the antennae forwards.” Thomas Say, 1824.

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