Hylaeus cornutus Curtis,1831

Synonyms

Hylaeus plantaris SMITH 1842; Hylaeus plumicornis COSTA 1884

Description and notes

Unique among British bees in carrying at least part of the pollen load in a shallow depression on the lower part of the face, the depression being bounded on each side by a usually prominent blunt process (hence the origin of its specific name).

Distribution

Southern England, from East Devon to Kent, northwards to Wiltshire, Berkshire, Warwickshire, Oxfordshire, Northamptonshire, Cambridgeshire, Suffolk and Norfolk. There are no records from Ireland. Generally a rare species, though in recent years there has been a noticeable increase of records from various sites within its range. A similar increase has been noted in Holland (Koster, 1986b). Widely distributed in central and southern Europe, north Africa, Anatolia and the Caucasus (see distribution maps in Koster, 1986a and 1986b).

Status (in Britain only)

Provisionally listed as a Rare species (pRDB3) by Falk (1991).

Habitat

Includes open deciduous woodland, fenland and, especially, calcareous grassland.

Flight period

Univoltine; early June to late August. Females, as with other British Hylaeus species, appear to be long-lived, in contrast to the males which are only found close to the beginning of the flight period.

Pollen collected

Not known, though probably polylectic, as in Germany (Westrich, 1989). Most Hylaeus ingest both pollen and nectar and regurgitate these products directly into the nest cells. These bees lack pollen-collecting hairs (scopae), though females of H. cornutus collect some pollen (apparently mixed with nectar) in the facial depression (C O’Toole and G R Else, pers. obs.). This interesting behaviour, seemingly unique among Hylaeus species worldwide, deserves closer investigation.

Nesting biology

Nests have been rarely found. One was in a dead dock (Rumex) stem (Smith, 1855) and another in a dead wild parsnip (Pastinaca sativa) stem (specimen in the University Museum, Cambridge). It also nests in herbaceous stems on the continent (Janvier, 1972; Koster, 1986a).

Flowers visited

Wild mignonette (Reseda lutea), lesser stitchwort (Stellaria graminea), field scabious (Knautia arvensis), yarrow (Achillea millefolium), angelica (Angelica sylvestris), hogweed (Heracleum sphondylium), wild carrot (Daucus carota) and ox-eye daisy (Leucanthemum vulgare). Pre-mating has been observed on the inflorescences of hogweed (Heracleum sphondylium)(Morris, 1992), and a coupled pair has been observed on wild carrot (Daucus carota) (G R Else, pers. obs.).

Parasites

No information available.

Author of profile

G R Else.

Year profile last updated

2001

Proofed: January 2012