Chelostoma campanularum (Small Scissor-bee)
The smaller of our two Chelostoma's (body length 5-6mm). Females have a rather inconspicuous pollen basket below the abdomen and lack any white bands on the tergites. The mandibles and labrum are not enlargened (very conspicuously lengthened in florisomne). Males have a small, rounded projection on sternite 2 (large and wedge-shaped in florisomne) and have simple antennae.

This tiny mason bee can be found widely across the southern half of England and can be locally common in some districts (though easily overlooked). It will use a variety of semi-natural habitats with plentiful Harebell (the main forage plant), including chalk downland, heathland and less improved grasslands. It is also frequent in gardens where it will exploit various cultivated Campanula's and may use Geranium species for nectar and as a subsidiary pollen source. Adults can often be found sheltering inside Campanula flowers during dull weather.

Nesting occurs in small beetle holes in dead wood, including old stumps, fence-posts, wooden sheds and the timber of old timbered buildings (some nice colonies are associated with some of the Shakespeare buildings in Stratford-upon-Avon). Adults fly from June until August.

This is one of two solitary bees that rely heavily on bellflowers like Harebell as a source of pollen. the other is the much larger Melitta haemorrhoidalis.

BWARS account:
www.bwars.com/index.php?q=bee/megachilidae/chelostoma-cam...
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