BRITISH BLOWFLIES (CALLIPHORIDAE) AND WOODLOUSE FLIES (RHINOPHORIDAE)

Draft key to British Calliphoridae and Rhinophoridae Steven Falk 2016
Eurychaeta – false fleshflies
Another blowfly genus containing species that do a good impersonation of flies of
another family, in this case Sarcophaga fleshflies (Sarcophagidae). In fact, these flies
were classified as sarcophagids until relatively recently and E. palpalis is the
Helicobosca distinguenda of van Emden’s 1954 sarcophagid key and Kloet & Hincks
(1976). The resemblance in the field is quite uncanny though numerous differences
are revealed under magnification. However, transfer of the genus from the
Sarcophagidae to the Calliphoridae by Rognes (1986) was strongly refuted by Lehrer
(2007) and it is treated as part of the sarcophagid subfamily Paramacronychiinae in
The Flesh-Flies of Central Europe (Povolný, & Verves 1997). The treatment here as a
calliphorid follows the NBN checklist and GBIF.
Eurychaeta species are snail scavengers. A single large larva is deposited on a dead or
dying pulmonate snail and the larva devours the entire shell contents before either
pupating within the shell or in soil nearby. Adults will visit flowers.
This is a small Palaearctic genus (4 species) with two European representatives. The
other, E. muscaria is a central and southern European species with much broader
parafacialia that only bear a single strong bristle (3-4 present in E. palpalis).
Eurychaeta palpalis (Robineau-Desvoidy, 1830)
False fleshfly
Description & similar species WL 7.5-10mm. A fairly large, strongly-bristled, black
and grey marked species most likely to be overlooked as a female Sarcophaga,
though the abdomen is not quite as neatly tessellated, the bristles are much stronger,
the parafacialia much narrower (with several very strong bristles), the proepisternal
depression (in front of the anterior thoracic spiracle) hairy and the palpi bright orange.
The aristae are densely short-plumose. The male frons is about one-quarter the width
of the head, that of the female about one-third.
Variation Moderate size variation.
Flight season May to August.
Habitat & biology Mostly recorded in scrubby calcareous grassland, the rides and
sunny margins of woodland, and alongside hedges. Adults visit flowers such as Wood
Eurychaeta palpalis pinned male (left) and living female (right)
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