BRITISH BLOWFLIES (CALLIPHORIDAE) AND WOODLOUSE FLIES (RHINOPHORIDAE)

Draft key to British Calliphoridae and Rhinophoridae Steven Falk 2016
Bellardia – emerald-bottles
Medium-sized, rather robustly-built blowflies, usually with the tergites glossy
greenish (sometimes bronze or turquoise-blue) but with a shifting dust pattern that
mutes the colour. The thorax is more heavily grey-dusted with shifting stripes on the
mesonotum but usually retains a trace of metallic colour. The lower calypters of most
species have long upright hairs on basal section of the upper surface. The head
capsule and antennae typically have an entirely dark ground colour (a little red can be
present on the antennae) and never exhibit the extensive reddish or orange areas of
many Calliphora species, and the antennae are much shorter. B. pubicornis (formerly
Pseudonesia puberula) is aberrant in various respects, lacking metallic reflections,
lacking hairs on the top of the lower calypters and having a rather protruding
mouthedge.
The biology is only known for a few species. Females are viviparous and the larvae
develop as internal parasitoids of earthworms. B. bayeri appears to specifically select
earthworms under loose bark of fallen trees and other dead wood. Most other species
occur in a variety of habitats but B. pubicornis is strongly boreal and only found in the
north and west of Scotland. Adults are occasional flower-visitors but are more likely
to be seen on foliage.
This is a Palaearctic genus with over 50 described species. A number of further
species occur on the near continent (see Rognes, 1991 and Huijbregts, 2002) and B.
bayeri is a fairly recent discovery in Britain. In addition to the potential for further
Bellardia species to turn up, attention should also be drawn to Onesia floralis (also
found on the near continent). It looks almost identical to a Bellardia in the field but
has a no presutural intra-alar bristle but three postsutural ones (Bellardia species have
a presutural one and two postsutural ones) and broader parafacialia.
Male Bellardia are relatively easy to identify using genitalia (safer than using
chaetotaxy) and checking genitalia is the best way to spot any extra species, including
O. floralis.
Key to species
1 Tergites not obviously metallic-green, turquoise or bronze (at most a hint of
bronze). Lower calypters usually without erect hairs on upper surface. Viewed
from side, mouth edge clearly protruding further than the frons (Fig 1). Upcurved
section of vein M relatively straight. Male genitalia Fig 6.......................pubicornis
- Tergites obviously metallic-green, turquoise or bronze. Lower calypter with erect
dark hairs on upper surface, at least basally. Viewed from side, mouth edge not,
or barely, protruding further the frons (Fig 2). Upcurved section of vein M usually
distinctly curved................. …………………………………………………….....2
2 Front tibiae with two strong posteroventral bristles. Section of costa between the
end of the subcosta and R1 with some ventral-facing hairs on lower surface (best
seen by viewing the wing directly from the front). Male genitalia Fig 7…...pandia
- Front tibiae with one posteroventral bristle. Section of costa between the end of
the subcosta and R1 without anyventral-facing hairs on lower surface.…………..3
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