Brachychaeteuma bradeae (Brölemann, H.K. Brade-Birks & S.G. Brade-Birks, 1917)

Status:

  • GB IUCN status: Least Concern
  • GB rarity status: Nationally Scarce

ID Difficulty

Identification

This species is identical in appearance to Brachychaeteuma bagnalli, with eyes comprising about three poorly pigmented ommatidia. The two can only be separated by dissection of male gonopods (female and immature specimens cannot be identified).

However, the two taxa have very variable gonopods and may yet prove to belong to a single, variable species (Blower, 1986).

J.P. Richards
Keith Lugg
J.P. Richards
J.P. Richards

Distribution

Although its range overlaps with that of B. bagnalli extending northwards to Perthshire, this species has been recorded most frequently in the Home Counties and East Anglia. It is apparently absent from Ireland. The more easterly distribution of B. bradeae in Britain fits with the Central European distribution pattern recognised by Kime (2001)

Habitat

Gregory & Campbell (1996) typically found B. bradeae in ancient woodlands on clay in Oxfordshire (an area where B. melanops occurs in synanthropic sites) but analysis of the habitat data suggests a strong association with cultivated sites. The strong synanthropic association shown by B. bagnalli is not so evident for B. bradeae but this may be due to the smaller number of records. It is usually collected from the underside of surface debris such as logs and stones but Jeekel (2001) found it in moles’ nests on peaty soil in meadows near Amsterdam. Many of the records from continental Europe are from synanthropic situations (Kime, 2001) but Schubart & Husson (1937) found this species in caves in north west France. It also occurs in Germany (Schubart, 1930), the Netherlands (Jeekel, 2001) and Sweden (Lohmander, 1925). 

Phenology 

As with B. bagnalli, this is an annual species that is adult in the winter and early spring although individuals have been collected as late as June. 

This species account is based on Lee (2006).

BRC code

40

idBmigTaxa

Mil_140