Hylaeus dilatatus – Chalk Pits- Cambridge

Status (in Britain only)
The bee is not regarded as scarce or being threatened.
The species is often locally common on calcareous grassland, but has been reported from coastal sites, fens and open woodland.
Flight period
Univoltine; early June to late August or early September. As with all British Hylaeus, the females are often long lived (the males having a considerably shorter adult life).
Nesting biology
The species has been reared on several occasions from burrows in dead bramble and rose stems in which the pith has been exposed (pers. obs.). There are additional records from other dead stems such as dock and mugwort (Smith 1876; Peeters, Raemakers, & Smit 1999, respectively). O W Richards (1930) observed the bee nesting in burrows in rotten fence posts.
Flowers visited
Bramble (Rubus fruticosus agg.), cinquefoil (Potentilla sp.), common fleabane (Pulicaria dysenterica), creeping thistle (Cirsium arvense), field bindweed (Convolvulus arvensis), hogweed (Heracleum sphondylium), pale toadflax (Linaria repens), sea spurge (Euphorbia paralias), wild carrot (Daucus carota) and yarrow (Achillea millefolium).
The gasteruptiid wasp Gasteruption assectator has been reared from nests of H. dilatatus in mainland Europe (Höpper 1904) and may parasitise this species in Britain…BWARS